Friday, 26 August 2016

CELL CYCLE (215 Qs)


The cell is the structural and functional unit of all organisms. The growth and development of an organism depend on the growth and development of the cell. The as an entity shows its own life cycle on par with the life cycle of the organism to which it belongs.

Now read the following questions and answers and suggest some more questions for the aspirants for competitive exams. Please help us rectify the mistakes and improve the content.


QUESTIONS & ANSWERS

1) What is the series of events in a cell that tames place from one division to the other?
A) Cell cycle
2) What is the way to avoid ageing or senescence in living organisms?
A) Cell division
3) By which process a certain degree of plasticity and immortality is provided to an organism?
A) Cell division
4) What is the direct cell division?
A) Amitosis
5) What is the indirect cell division?
A) Mitosis
6) What is the most primitive form of cell division?
A) Amitosis
7) What is the chief method of multiplication and growth in unicellular organisms?
A) Amitosis
8) Which is the most common type of amitosis in unicellular organisms?
A) Fission (Binary fission)
9) What are the three periods of a cell cycle in bacteria?
A) B, C, D phases
10) When do DNA replication and cell division take place in bacteria?
A) D phase
11) What are the two periods  of a cell cycle in an eukaryotic cell?
A) Interphase & Cell division phase
12) What is the phase of non-apparent cell division or resting phase?
A) Interphase
13) What is the metabollically most active phase of the cell cycle?
A) Interphase
14) Who referred interphase as the energy phase?
A) Berril and Huskins
15) What is the preparatory phase in the cell cycle?
A) Interphase
16) What is the inter-mitotic phase?
A) Interphase
17) What percentage of the cell cycle  is the interphase?
A) 90%
18) What are the three sub-phases of interphase?
A) G1 phase, S phase and G2 phase
19) What are the gap phases of the cell cycle?
A) G1 & G2 phases
20) What is the synthetic phase of the cell cycle?
A) S phase
21) What is the point at which the previous stage is stopped and the next stage of the cell cycle starts?
A) Restriction point
22) Who discovered cleavage in animal cells?
A) Prevost and Dumas
23) What are the two types of cell divisions in eukaryotic cells?
A) Mitosis & Meiosis
24)Who discovered mitosis? A) W Flemming
25) Which is the somatic cell division?
A) Mitosis
26) In what kind of cell division daughter cells are formed with similar sizes and chromosomal sets?
A) Mitosis
27) In which phase of the cell cycle RNAs are produced?
A) G1 phase
28) In which phase DNA replication occurs?
A) S phase
29) In which phase of the cell cycle organelles are produced?
A) G1 & G2 pleases
30) In which phase of the cell cycle centrioles and mitotic spindle tubules are formed?
A) G2 phase
31) What is the period of intense synthesis and growth in a cell cycle?
A) Interphase
32) What are the two periods of cell division?
A) Karyokinesis & Cytokinesis
33) Who discovered karyokinesis and cytokinesis as two phases of a cell division?
A) Remak and Kolliker
34) Who introducrd the term karyokinesis?
A) Schleicher
35) Who introduced the term cytokinesis?
A) Whiterman
36) What percentage of the cell cycle is mitosis?
A) 10%
37) What are the four phases of karyokinesis?
A) Prophase, metaphase,  anaphase & telophase
38) What is the time period of a bacterial cell cycle?
A) 20 minutes
39) What is the time period of a cell cycle in onion root tip cells?
A) 20 hours
40) What is the time period human cell cycle in culture at 37°C?
A) 20 hours
41) What is the time period required for a human cell to complete  one mitotic phase in culture at 37°C?
A) 1 hour
42) What are the never dividing cells in the human body?
A) Nerve cells or neurons
43) Which is the longest mitotic phase?
A) Prophase
44) In which phase of mitotic division chromosomes appear?
A) Prophase
45) In which mitotic phase chromatin reticulum reappear?
A) Telophase
46) What is the point of attachment of chromatids?
A) Centromere
47) In which mitotic phase disorganization of the nucleus takes place?
A) Prophase
48) In which mitotic phase reorganization of the nucleus takes place?
A) Telophase
49) Which phase is the reverse of prophase?
A) Telophase
50) When do spindle fibres start appearing in mitosis?
A) Metaphase
51) What is the epicentre of spindle formation during cell division?
A) Centriole
52) Which cell organelle is meant for organizing spindle fibres?
A) Centriole
53) Which cell organelles are the basic components of spindle fibres?
A) Microtubules
54) How many centrioles are required per a cell to form spindle fibres?
A) Two
55) How is called a centriole with radiating microtubules at the helm of spindle fibres?
A) Aster
56) How do you call the mitosis with asters?
A) Astral mitosis
57) How do you call the mitosis without asters?
A) Anastral mitosis
58) In what kind of cells astral mitosis is common?
A) Animal cells
59) In what kind of cells anastral mitosis is common? A) Plant cells
60) Why does anastral mitosis take place in plant cells?
A) Due to absence of centrioles
61) What is the junction of spindle fibres and chromatids ?
A) Centromere
62) What is the mode of arrangement centromeres on the equatorial plate?
A) Radial
63) At which stage of cell division the equatorial plate is broken?
A) Anaphase
64) Which is the shortest phase of mitosis?
A) Anaphase
65) When does the division of centromeres take place?
A) Anaphase
66) When do chromosomes reach opposite poles?
A) Anaphase
67) What are the different shapes of chromosomes during anaphase?
A) V, J & I shaped
68) What are V-shaped chromosomes?
A) Metacentric or isobranchial chromosomes
69) What are J-shaped chromosomes?
A) Subetacentric or  heterobranchial chromosomes
70) What are I-shaped chromosomes?
A) Acrocentric chromosomes
71) What is the division of the nucleus?
A) Karyokinesis
72) What is the division of  cytoplasm?
A) Cytokinesis
73) In what kind of cells cytokinesis stars with furrows?
A) Animal cells
74) In what kind of cells cytokinesis  is through a cell plate formation?
A) Plant cells
75) What is the equatorial plate impregnated with spindle fibres in plants?
A) Phragmoplast
76) Which cell organelle secretes cell wall components?
A) Golgi apparatus
77) Which cell organelle is required to form pasmodesmata?
A) Endoplasmic Reticulum
78) What is the extension of endoplasmic reticulum in plasmodesmata?
A) Desmotubule
79) What kind of cell division leads to genetic stability?
A) Mitosis
80) What kind of reproduction occurs due to mitosis?
A) Asexual reproduction
81) What kind of reproduction occurs due to meiosis?
A) Sexual reproduction
82) What is the basis for growth,  repair and replacement of somatic cells?
A) Mitosis
83) Which is the equational or homoeotypic cell division?
A) Mitosis
84) Which is the reduction or heterotypic cell division?
A) Meiosis
85) In what kind of cell division one karyokinesis and one cytokinesis occur?
A) Mitosis
86) In what kind of cell division two karyokineses and one cytokinesis occur?
A) Meiosis
87) When is the chromosome number reduced to half during meiosis?
A) Meiosis I (Anaphase I)
88) What are the five subphases of meiosis I in sequence?
A) Leptotene, zygotene, pachytene, diplotene & diakinesis
89) Which is the reduction phase of the meiosis?
A) Meiosis-I
90) Which is the equational phase of the meiosis?
A) Meiosis-II
91) Which phase of meiosis is similar to that of mitosis?
A) Meiosis-II
92) In which subphase of meiosis chromomeres appear over chromosomes?
A) Leptotene
93) What are the similar chromosomes?
A) Homologous chromosomes
94) What is the pairing of homologous chromosomes? A) Synapsis
95) Which protein binds sister chromatids together?
A) Cohesin
96) Which enzyme separtes sister chromatids?
A) Separase
97) When does synapsis of homologous chromosomes take place?
A) Leptotene
98) How are the paired homologous chromosomes called?
A) Bivalents
99) When are chromosomal bivalents and tetrads are formed?
A) Zygotene stage
100) Which is the longest subphase of prophase-I?
A) Pachytene
101) When does crossing over take place?
A) Pachytene stage
102) When does new gene combinations occur during meiosis?
A) Pachytene stage
103) Which process leads to new gene combinations in a chromosome?
A) Crossing over
104) What are X-shaped structures formed after crossing over of homologous chromosomes?
A) Chiasmata
105) When does chiasmata  apper in meiosis?
A) Diplotene stage
106) When does terminalization of chiasmata take place?
A) Diakinesis
107) In what kind of cell division centromeres divide?
A) Mitosis & Meiosis-II
108) In what kind of cell division centromeres do not divide?
A) Meiosis-I
109) Which is the meiotic mitosis?
A) Meiosis-II
110) In what kind of cell division genetically similar daughter cells are formed?
A) Mitosis
111) In which type of cell division centromeres lie on the equator to let chromosomal arms face the poles?
A) Mitosis & Meiosis-II
112) In which type of cell division centromeres lie  towards the poles to let chromosomal arms face the equator?
A) Meiosis-I
113) What kind of cell division leads to the formation of haploid gametes?
A) Meiosis
114) How many daughter cells are formed after mitosis?
A) 2
115) How many daughter cells are formed after meiosis?
A) 4
116) What is the principal means of reproduction in unicellular organisms?
A) Cell division
117) In what kind of cell division the daughter cells have same ploidy?
A) Mitosis
118) At what stage of cell cycle histone proteins are formed?
A) S phase
119) In which kind of cell division chromosomal dyads appear along the equator?
A) Mitosis & Meiosis-II
120) In which kind of cell division chromosomal tetrads appear along the equator?
A) Meiosis-I
121) What kind of cell division leads to the formation of pollen dyads or tetrads?
A) Meiosis
122) In which phase of cell division random distribution of chromosomes take place?
A) Anaphase
123) Which type of cell division occur in all types of cells?
A) Mitosis
124) In what kind of mitosis the nuclear envelope is broken?
A) Open mitosis
125) In what kind of mitosis the nuclear envelope is not broken?
A) Closed mitosis
126) Name a multicellular fungus with closed type of mitosis?
A) Aspergillus nidulans
127) Name a unicellular fungus with closed type of mitosis?
A) Saccharomyces cerevisiae
128) What is the process of replication of DNA during S phase without the subsequent completion of mitosis and cytokinesis. ?
A) Endoreplication
129) What is the result of endoreplication followed by karyokinesis but not cytokinesis in fungi and slime molds?
A) Coenocyteformation
130) What will be the result of repeated replication of DNA without forming new nuclei in telophase?
A) Polyploidy & Polyteny
131) Which process leads to the formation of "giant" chromosomes?
A) Polyteny
132) How many DNA strands does a Polytene chromosome in salivary glands of Drosophila  possess?
A) 2048
133) What is the phenomenon of occurrence of more than two sets of chromosomes in a cell?
A) Polyploidy
134) Where are the polyploid cells occur in human beings?
A) Hepatocytes & megakaryocytes
135) What are the giant human cells that are formed due to seven S phases with nucleus containing ploidy 128n chromosomes?
A) Megakaryocytes
136) What are formed due to the fragmentation of megakaryocytes?
A) Blood platelets
137) Which hormone regulates the cell cycle?
A) Cyclin
138) Which enzyme regulates the cell cycle?
A) Kinase
139) Who got Nobel Prize for the discovery of cyclin and CDKs?
A) Hartwell, Hunt, and Nurse
140) What are CDKs?
A) Cyclin-dependent kinases
141) What are the major control switches for the cell cycle?
A) Cyclin and CDKs
142) What is the anaphase-promoting complex (APC)? A) Cyclosome
143) What is the result of mitosis followed by too many or too few chromosomes?
A) Aneuploidy
144) What are the five phases of occasionally dividing cells?
A) G1, G0, S, G2 & M phase
145) How is called the G0  stage cell?
A) Quiescent cell
146) What are the common quiescent cells in human body?
A) Erythrocytes, neurons, myocytes, adipocytes,  etc
147) What are the common quiescent cells in human body that renter G1 phase from G0 phase after getting stimulus?
A) T- & B- lymphocytes
148) What are the only two phases in the cell cycle of quiescent cells?
A) G1 & G0 phases
149) Which mutation is the most frequent cause for cancer?
A) p53 mutation
150) Which disease is caused due to non-regulation of the cell cycle?
A) Cancer
151) What are the cancer causing genes?
A) Oncogenes
152) What is meant by uncontrolled, abnormal growth or division of cells?
A) Cancer
153) What is the abnormal growth of a cell?
A) Hypertrophy
154) What is the abnormal growth of a tissue due to uncontrolled cell divisions?
A) Hyperplasia
155) What is the symptom of unwanted growth of a cell?
A) Tumour
156) What are the non-cancerous tumours?
A) Benign tumours
157) What are the cancerous tumours?
A) Malignant tumours
158) What is the process of transfer of cancerous cells from one part to the other part of a body?
A) Metastasis
159) What kind of cells never enter G0 phases, but show repeated indefinite cell cycles?
A) Cancer cells
160) What is the cancer of epithelial cells?
A) Carcinoma
162) What are the body parts that may be affected by carcinoma?
A) Breast, lung, pancreas, stomach, etc
163) What is the cancer of muscle cells?
A) Sarcoma
164) What are the body parts that may be affected by Sarcoma?
A) Muscles & lymph nodes
165) What is the cancer of lymphocytes  (WBC)?
A) Leukaemia
166) What are the cancer causing agents?
A) Carcinogens
167) What kind of strong radioactive rays are used to kill cancerous cells?
A) X-rays & Gamma rays
168) What are the physical carcinogens?
A) Radioactive rays
169) Name the fungus toxin or mycotoxin that causes cancer.
A) Aflatoxin
170) What are the biological cancer causing agents?
A) Viruses
171) What is meant by apoptosis?
A) Programmed or suicidal death of a cell
172) At what stage of cell cycle sister chromatids are formed?
A) S stage
173) When does disjunction  of chromatids take place?
A) Anaphase
174) How is called a set of four chromatids in a homologous bivalent?
A) Tetrad
175) What is the number of possible arrangements of chromosomes during metaphase-I of meiosis-I, if n is the number of chromosomes in a haploid set?
A) 2n
176) What is the number of possible arrangements of chromosomes in human cells during metaphase-I of meiosis-I
A) 8 million
177) How does meiosis generate genetic diversity?
A) crossing over during  Meiosis-I, random alignment of chromosomes in Meiosis-I and random alignment of the sister chromatids at Meiosis-II
178) What is must for the cell division to happen?
A) Doubling of genome (DNA) during S phase
179) By which process doubling of genome  (DNA) occur?
A) Replication
180) When does the genome become half?
A) Mitosis
181) Which alkaloid is used to interfere with spindle formation and cell division?
A) Colchicine
182) Which nutrient element has its marked effect of the size and structure of chromosomes?
A) Phosphorus
183) What is the time required for a typical eukaryotic cell to divide once?
A) Approximately every 24 hours
184) What is the time required for a yeast cell to divide once?
A) Approximately every 90 minutes
185) Which ratio decides a cell to divide?
A) N:C ratio
186) What is N:C ratio or N/C ratio?
A) Nuclear-cytoplasmic ratio
187) What is N:C ratio of blasts for the formation of
erythrocytes, leukocytes, and megakaryocytes?
A) 4:1
188) Who discovered mitosis?
A) Otto Butschli
189) Who coined the term  "mitosis? "
A) Walther Flemming
190) Who described mitosis  for the first time?
A) Mayzel
191) What is the literal meaning of the word mitosis?
A) "warp thread"
192) What is genome replication without cell division?
A) Endoreplication, endoreduplication or polytenization
193) What is called the repeated endoreplication without  mitosis?
A) Endocycling
194) What is mitosis without karyokinesis and cytokinesis
A) Endomitosis
195) What is the advantage of Endomitosis?
A) Polyploidy
196) What are the cells that undergo meiosis?
A) Meiocytes or germ cells
197) What are the meiocytes in anthers?
A) Pollen Mother Cells or Microspore Mother Cells
197) What are the meiocytes in gynoecium?
A) Pollen Mother Cells or Microspore Mother Cells
A) Megaspore Mother Cells
198) What are the meiocytes in testes?
A) Spermatocytes (in seminiferous tubles)
199) What are the meiocytes in human ovaries?
A) Oocytes
200) What kind of cell divisions are required to form liquid endosperm in coconut water?
A) Free Nuclear Divisions
200) What kind of cell divisions are required to form solid endosperm in coconut meat?
A) Cellular  Divisions
201) What is the process of exchange of genetic material between homologous chromosomes?
A) Crossing over
202) What kind of alleles are formed due to crossing over?
A) Recombined alleles
203) What are the versions of genes in a gene pair?
A) Allele
204) Who described crossing over for the first time?
A) Thomas Hunt Morgan
205) Who first demonstrated physical basis of crossing over?
A) Harriet Creighton and Barbara McClintockin
206) What could be the DNA repair process in meiosis?
A) Crossing over
207) Which reproductive method of bacteria is similar to crossing over?
A) Transformtion
208) What is the contact between two chromatids that will undergo crossing-over?
A) Chiasma
209) Which organelle regulates the spindle formation in animal cells?
A) Centrosome
210) How many centrioles does a centrosome provide for spindle formation?
A) Two
211) In what kind of life cycle zygotic meiosis takes place?
A) Haplontic life cycle
212) In what kind of life cycle gametic meiosis takes place?
A) Diplontic life cycle
213) In what kind of life cycle sporic meiosis takes place?
A) Haplodiplontic life cycle
214) What are the cells or individuals that are diploid?
A) Diplonts
215) What are the cells or individuals that are formed due to meiosis?
A) Haplonts

Monday, 22 August 2016

CELL - GENERAL (175 Qs)


The cell is the basic unit of structure and function in any organism. It is a unit quantity of living substance that is protoplasm bounded a unit membrane. The structure and functioning of all cells together reflect on the existence or well-being of the entire organism.

Now read the following questions and answers and suggest some more questions for the aspirants for competitive exams. Please help us rectify the mistakes and improve the content.


QUESTIONS & ANSWERS

1) What is the structural and functional unit of all organisms?
A) Cell
2) When did living cells originate on the Earth?
A) 3.5 billion years ago.
3) What is the smallest unit of life?
A) Cell
4) What are the building blocks of life?
A) Cells
5) Which branch of science deals with the study of cells?
A) Cytology
6) Which branch of science deals with the study of all aspecys of cells?
A) Cell biology
7) Who discovered cell?
A) Robert Hooke
8) Who coined the term cell?
A) Robert Hooke
9) With what Robert Hooke compared the cells in the cork?
A) With cells in the Christian monastery
10) Who discovered living cells?
A) Anton Van Leeuenhoek
11) Who discovered bacteria and protozoa?
A) Anton Van Leeuenhoek
12) Who coined the term cell wall?
A) Robert Hooke
13) What was the famous book written by Robert Hooke?
A) Micrographia
14) Who gave the first idea of cell theory?
A) Dutrochet
15) Who gave the cell theory for plants?
A) MJ Schleiden
16) Who gave the cell theory for animals?
A) Theodore Schwann
17) Who gave the cell theory?
A) Schleiden & Schwann
18) Who gave the cell lineage theory?
A) Rudolf Virchow
19) What is the famous phrase of Rudolf Virchow?
A) Omnis cellula e cellulae (all cells are formed from pre-existing cells)
20) Which discovery was a proof to Virchow's cell lineage theory?
A) Mitosis
21) Name some organisms which are exception to the cell theory?
A) Viruses, Paramecium, Rhizopus, Vaucheria
22) Who proposed organism theory?
A) Sachs
24) What are the mammalian cells without respiration and replication?
A) RBCs
25) What are the mammalian cells without a nucleus?
A) RBCs
26) What are the plant cells without nucleus?
A) Sieve Tubes
27) Why the RBCs cannot replicate?
A) Nucleus or DNA is absent
28) Why the RBCs cannot respire?
A) Absence of mitochondria
29) What are the nucleated animal cells which cannot differentiate?
A) Nerve cells
30) What is the ability of a cell to reproduce to a complete organism?
A) Totipotency
31) Who induced morphogenesis in plant callus for the first time?
A) Skoog & Miller
32) Who established the concept of cellular totipotency?
A) Steward et al.
33) What are the energy transducers in plant cells?
A) Chloroplasts
34) Why are the smaller cells metabolically efficient?
A) Higher nucleo-plasmic ratio & surface volume ratio
35) What would happen to the surface volume ratio if the size of a cell is doubled?
A) Surface volume ratio decreases by half
36) What is the chief function of microvilli?
A) to increase surface area for absorption
37) What is a rod shaped bacterium?
A)  Bacillus
38) What is a spherical shaped bacterium?
A)  Coccos
39) What is a comma shaped bacterium?
A)  Vibrium
40) What is a spiral shaped bacterium?
A)  Spirillum
41) Name the prokaryote whose shape keeps on changing?
A) Mycoplasma
42) Name the protozoan whose shape keeps on changing?
A) Amoeba
43) What are the amoeboid cells in the human body?
A) Leucocytes  (WBCs)
44) Which is the largest unicellular organism?
A) Acetabularia (marine alga)
45) Which is the umbrella shaped unicellular alga?
A) Acetabularia
46) Which is the longest cell?
A) Fibre cell of Boehmeria nivea (Ramie)
47) Which is the longest animal  cell?
A) Nerve cell
48)Which is the smallest cell?
A) PPLO (Pleuro Pneumonia Like Organisms)
49)Which is the largest cell?
A) Ostrich egg
50) Who coined the terms prokaryotic and eukaryotic cells?
A) Dougherty
51) What are the organisms with an indistinct diffused nucleus?
A) Prokaryotes
52) What are the organisms with a distinct nucleus?
A) Eukaryotes
53) Which is the prokaryotic organism without a cell wall?
A) Mycoplasma
54) Which is the smallest prokaryotic cell?
A) PPLO (Pleuro Pneumonia Like Organisms)
55) Where is a double stranded circular naked DNA present?
A) Prokaryotes,  mitochondria & plastids  (chloroplasts)
57) What are the organisms without membranous organelles?
A) Prokaryotes
58) What are the cells within cells?
A) Mitochondria and chloroplasts
59) What are the organelles within organelles?
A) Ribosomes in mitochondria and chloroplasts
60) Where are 70S ribosomes present?
A) Prokaryotes,  mitochondria and plastids  (chloroplasts)
61) What are cyanobacteria? A) Blue-green algae
62) What are the units of golgi apparatus in plant cells?
A) Dictyosomes
63) What kind of microbodies are absent in animal cells?
A) Glyoxysomes
64) What is the outermost layer of animal cells?
A) Cell membrane
65) What is the outermost layer of plant  cells?
A) Cell wall
66) What is the biggest organelle in animal cells?
A) Nucleus
67) What is the biggest organelle in mature plant  cells?
A) Vacuole
68) Why are animal cells heterotrophic?
A) Due to absence of chloroplasts
69) Why are plant cells autotrophic?
A) Due to presence of chloroplasts
70) What kind of cells possess centrioles?
A) Animal cells
71) Why do animal cells burst when they are kept in hypotonic solution?
A) Due to lack of cell walls
72) Which is the unit of measurement in light microscopes?
A) Micron
73) What is the unit of measurement in electron microscopes?
A) Angstrom
74) What are the organisms that can be seen only under electron microscope?
A) Viruses and PPLOs or mycoplasmas
75) What are the cell structures that can be seen under light microscope?
A) Cell wall, nucleus,  chloroplasts and mitochondria
76) What are the cell structures that can be seen under electron microscope only?
A) Ribosomes,  endoplasmic reticulum,  cell membrane, lysosomes,  microbodies, etc
77) What are the jokers of the plant kingdom?
A) Mycoplasmas
78) In what kind of organisms the respiratory enzymes areassociated with cell membranes?
A) Prokaryotes
79) What are the structures in bacterial cells comparable with mitochondria?
A) Mesosomes
80) What is the primitive nucleus of prokaryotes?
A) Chromomere, genophore, incipient nucleus or nucleoid
81) What type of cell division is common among prokaryotic cells?
A) Amitosis
82) What type of cell divisions are common among eukaryotic cells?
A) Mitosis & meiosis
83) What kind of cells have 80S ribosomes?
A) Eukaryoticcells
84) How many cells a human body has?
A) more than 10 trillion cells
85) What were the first living forms on the Earth?
A) Prokaryotes
86) What are the extra-chromosomal DNA elements in bacteria?
A) Plasmids
87) Where are antibiotic resistance genes located in bacteria?
A) On plasmids
88) What is the main distinguishing feature of eukaryotes as compared to prokaryotes?
A)  Compartmentalization (organelles)
89) What is the main organizer and maintainer of the eukaryotic cell's shape?
A) Cytoskeleton
90) What are parts of the cell which are specialized for different vital functions?
A) Organelles
91) What are the solitary cell organelles in a typical cell?
A) Nucleus & Golgi apparatus
92) What are the liquid filled spaces surrounded by a membrane?
A) Vacuoles
93) Who described single celled organisms as animalcules?
A) Anton van Leeuwenhoek
94) Who first observed muscle fibres, spermatozoa and blood cells under microscope?
A) Anton van Leeuwenhoek
95) Who invented the first compound microscope?
A) Zacharias Jansen
96) Who designed the first electron microscope?
A) Max Knoll & Ernst August Friedrich Ruska
97) Who discovered nucleus?
A) Robert Brown
98) Who discovered cytoplasmic streaming?
A) Robert Brown
99) Who discovered mitochondria?
A) Richard Altmann
100) How did Altmann call mitochondria?
A) Bioblasts
101) Who coined the term "mitochondria?
A) Carl Benda
102) Who discovered Janus green as supra vital stain for mitochondria?
A) Leonor Michaelis
103) Who discovered chloroplasts?
A) Julius von Sachs
104) Who discovered  9 + 2 microtubule structure in cilia?
A) Keith Roberts Porter
105) Who coined the term endoplasmic reticulum?
A) Keith Roberts Porter
106) Who discovered peroxisome and lysosome?
A) Christian René Marie Joseph Viscount de Duve
107) Who is considered "the most influential cell biologist ever"
A) Palade
108) Who discovered ribosomes on endoplasmic reticulum?
A) Palade
109) Who discovered double helical model of DNA?
A) Watson & Crick
110) Who discovered the chromosomal movements in mitosis?
A) Flemming
111) Who described sarcosomes and later they come to be known as the mitochondria?
A) Albert von Kölliker
112) What is the study of nucleus?
A) Karyology
113) What are the most primitive forms of life on the Earth?
A) Prokaryotes
114) What kind of other cells form about 95% of all the cells in the human body?
A) Bacteria
115) What is the term used to describe the suicide committed by cells?
A) Apoptosis
116) What are the human cells with longest life span?
A) Neurons
117) What is the smallest objects that the unaided human eye can see?
A) About 0.1 mm long
118) What is the maximum possible power of a light microscope as it is limited by the wavelength of visible light?
A) 500 nm
119) What is required to see anything smaller than 500 nm?
A) Electron microscope
120) What is the size of most bacterial cells?
A) 0.2 to 10 microns
121) What is the size of Amoeba proteus?
A) 250 to 750 microns
122) What is the size of most animal cells?
A)10 to 100 microns
123) What is the diameter of an RBC?
A) 8 microns
124) What is the length of a giraffe's nerve cell?
A) 2 meters (about 6 feet)
125) What is the length of an ostrich egg cell?
A) 6 inches (half foot)
126) What is the size of a human egg cell?
A) 100 microns
127) What is the size of a ramie fibre, longest cells in the plant kingdom?
A) 13 to 15 cm (5 to 6 inches)
128) What is the instrument used to see objects that are too small for the naked eye?
A) Microscope
129) Which is the most common microscope?
A)  Optical microscope or light microscope
130) What was the first microscope to be developed?
A)  Optical microscope or light microscope
131) Who coined the term microscope for Galileo Galilei's compound microscope?
A) Giovanni Faber
132) What are the branches of microscopy?
A) Optical, electron, and scanning probe microscopy
133) What are the microscopes functioning on visible light?
A) Optical or light microscopes
134) Which is the most advanced light  microscope? A) Digital microscope & Fluorescents microscope
135) Which is the simplest of all the light microscopy techniques?
A) Bright field microscopy
136) How could we get the 3-dimensional image in a light microscope?
A) By oblique illumination
137) What is the technique for improving the contrast of unstained, transparent specimens?
A) Dark field microscopy
138) What is the optical technique that results in a coloured image of a colourless object?
A) Dispersion staining
139) What is the microscopic technique to show differences in refractive index?
A) Phase contrast
140) Who invented the phrase contrast microscope?
A) Frits Zernike
141) Who invented the first electron microscope or the transmission electron microscope (TEM)?
A) Ernst Ruska
142) What is used in the place of light in electron microscope?
A) Electrons
143) In what kind of microscopes photons are used?
A) Optical or light microscopes
144) What is used instead of lenses in electron microscope?
A) Electromagnets
145) Who invented the scanning electron microscope?
A) Max Knoll
146) Who invented the first scanning probe tunnelling  microscopes?
A) Gerd Binnig and Heinrich Rohrer
147) Who invented the atomic force microscope?
A) Gerbe
148) What is the magnifocation  limit of a light microscope?
A) up to 1250 X
149) What is the resolution limit of a light microscope?
A)  0.250 micrometres or 250 nanometres
150) What is the magnification of the simplest optical microscope (magnifying glass)?
A)  10X magnification
151) Which lens is at the top of a compound microscope to look through?
A) Eyepiece Lens
152) What is the general illuminator in a compound microscope?
A) Mirror or 100 volts light source
153) Which part of the microscope holds two or more objective lenses and can be rotated to easily change power?
A) Revolving Nosepiece or Turret
154) Which lens is kept near the object to see in the compound microscope?
A) Objective lens
155) What is the magnification power of objective lenses in a compound micriscope?
A) 4X, 10X, 40X and 100X
156) What is the rotating disc to vary intensity and size of the cone of light at the base of the stage?
A) Diaphragm
157) What are the components of the Gram stain used for bacteria?
A) Crystal violet, iodine and fuchsin or safranin
158)Which stain is used to mark bacterial cell walls?
A) Crystal violet
159)Which dye is used to stain cells of Mycobacterium tuberculosis?
A) Ziehl-Neelsen stain
160) Which dye stains the cell nucleus blue?
A) Haematoxylin
161) Which dye stains cytoplasm and RBC pink or bright red?
A) Eosin
162) Which dye is used to mark carbohydrates (glycogen, glycoprotein, proteoglycans)?
A) Periodic acid- Schiff staining
163) Which dye is a nucleic acid selective fluorescent cationic dye useful for cell cycle determination?
A) Acridine orange
164) What is used as an indicator for starch?
A) Iodine
165) Which dye is used to stain animal cells, such as human cheek cells, to make their nuclei more observable?
A) Methylene blue
166) Which is a red cationic dye that binds to nuclei (DNA),  cartilage, mast cells, lignin and plastids?
A) Safranine O
167) Which stain is used in optical microscopy to stain lipids?
A) Osmium tetroxide
168) From which part of Haematoxylum tree hematozylin dye is extracted?
A) Heartwood
169) Which is the common stain to observe mitochondria through a microscope?
A) Janus Green B
170) Which stain was used by Altmann to observe mitochondria?
A) Acid fuchsine
171) Which is the common acidophilic dye in microscopic studies?
A) Eosin
172) Which is the common basophilic dye in microscopic studies?
A) Janus Green B
173) What kind of stains are applied on living cells without killing them?
A) Vital stains
174) What are the common vital stains?
A) Eosin, Propidium iodide, Trypan Blue, Erythrosine, Amino actinomycin D,
Janus Green B
175) Which branch of science deals with the study of DNA and RNA?
A) Molecular Biology

Sunday, 21 August 2016

CELL WALL (117 Qs)

All bacteria, blue-green algae, fungi and plant cells (except mycoplasmas & slime molds) are surrounded and protected by a mechanical and rigid layer called cell wall. This is the layer which gives certain shape to an individual cell or the overall organism.

Now read the following questions and answers and suggest some more questions for the aspirants for competitive exams. Please help us rectify the mistakes and improve the content.



QUESTIONS & ANSWERS

1) What are the different cell wall containing organisms?
A) Prokarotes (bacteria & blue green algae), fungi and plants
2) What is the major difference between a plant cell and an animalcell?
A) Presence of cell wall
3) What are the prokaryotic cells without cell walls?
A) Mycoplasmas
4) What is the outermost layer of plant cells?
A) Cell wall
5) Which part of the plant cell provides rigidity and mechanical support?
A) Cell wall
6) Which part of the cell is helpful in the morphodgensis of plants?
A) Cell wall
7) Which part is helpful in protecting a plant cell against osmotic lysis?
A) Cell wall
8) What are two factors that provide rigidity to plant cells?
A) Hydraulic turgor and cell wall structure
9) What are the pressure vessels that  prevent over-expansion or bursting of plant cells due to excess entry of water?
A) Cell walls
10) Who first observed cell wall?
A) Robert Hooke
11) Who coined the term cell wall?
A) Robert Hooke
12) Who were the supporters of the apposition or lamellar theory of cell wall formation?
A) Hugo Von Mohl & Edward Strasburger 
13) Who were the supporters of the intursusception theory of cell wall formation?
A) Carl Nageli & Julius Wiesner
14) Which is the non-living part of the plant tissues?
A) Apoplast
15) Which is the living part of the plant tissues?
A) Symplast
16) Who coined the term apoplast?
A) Munch
17) Which is the extracellular matrix in plant cells?
A) Cell wall
18) What are the different layers of a typical cell wall?
A) Middle lamella, primary wall, secondary wall and tertiary wall
19) Which is the first formed cell wall layer?
A) Middle lamella
20) What is the basic structure on which the middle lamella will be formed?
A) Cell plate
21) What is the chief component of middle lamella?
A) Calcium and magnesium pectate
22) Which cementing layer holds all the cells in a plant tissue?
A) Middle lamella
23) What is the chief organic substance in middle lamella?
A) Pectin
24) What are the chief inorganic elements in middle lamella?
A) Calcium and magnesium
25) Which is the outermost layer of a plant cell wall?
A) Middle lamella
26) What are the polysaccharides in primary cell walls?
A) Cellulose, hemicellulose and pectin
27) Which enzyme catalyses the formation of cellulose cell wall?
A) Cellulose synthase
28) Which enzyme catalyses the disorganization of cellulose cell wall?
A) Cellulase
29) Which is the most abundant macromolecule on the earth?
A) Cellulose
30) Which is the most abundant protein on the earth?
A) Rubisco
31) What is the chief carbohydrate in plant cell walls?
A) Cellulose
32) What is the chief component of the primary wall, secondary wall or tertiary wall?
A) Cellulose
33) What is the chief component of bacterial cell walls?
A) Peptidoglycan, murein or muramic acid
34) What are the chemical components of the cell walls of gram positive bacteria?
A) Peptidoglycon & teichoic acid
35) What kind of bacteria contain a thin peptidoglyconic cell wall with a membrane made of  lipo-polysacccharides and lipoproteins?
A) Gram negative bacteria
36) What kind of bacteria do not contain peptidoglyconic cell walls?
A) Archaebacteria
37) Which group of archaebacteria contains pseudo-peptidoglycon in cell walls?
A) Methanogens
38) Which chemical is used to stain bacterial cell walls?
A) Gram stain
39) What are the two types of cell walls in bacteria?
A) Gram positive and gram negative
40) What kind of bacteria have thick cell walls?
A) Gram positive bacteria
41) What kind of bacteria have thin cell walls?
A) Gram negative bacteria
42) What are the major kind of bacteria on the basis of the nature of their cell walls?
A) Gram negative bacteria
43) What are the cell wall materials of archaean bacteria?
A) Glycoprotein S-layers, pseudopeptidoglycan, or polysaccharides
44) What is the glucosamine polymer in the cell walls of fungi?
A) Chitin
45) What are the fungi that contain cellulose cell walls?
A) Slime molds
46) What are the materials in the algal cell walls?
A) Glycoproteins and polysaccharides
47) What is the chief component in the algal cell walls?
A) Cellulose
48) What is the characteristic polysaccharide in the cell walls of brown algae (Phaeophyceae)?
A) Alginic acid
49) What kind of algae generally contain sulfonated polysaccharides like  agarose, carrageenan, porphyran, furcelleran and funoran?
A) Red algae (Rhodophyceae)
50) What is the characteristic cell wall material obtained from Gelidium, a red alga?
A) Agar-agar
51) What is the silicitated covering over the cell walls of foraminiferans?
A) Testa
52) Which group of alga contains biogenic silica in their cell walls?
A) Diatoms
53) What is the extracellular matrix around the cell walls of diatoms fromed of silicic acid?
A) Frustule or valve
54) Which chemical element in cell walls is an adaptation to protect grasses from herbivorous animals?
A) Silica
55) Which cell wall material gives flexibility to collenchyma?
A) Pectin
56) What kind of tissues possess only primary walls?
A) Meristems & Parenchyma
57) Which cell wall layer can allow the plant cell to grow?
A) Primary wall
58) What is the major component of secondary walls?
A) Cellulose
59) What is the phenolic polymer in secondary walls?
A) Lignin
60) What is the chief component of secondary wall of  sclerenchyma and teacheary elements?
A) Lignin
61) What are casparian thickenings on root endodermis made of?
A) Suberin
62) What is the chief component of  cork cell walls?
A) Suberin
63) What is the chief component of tertiary walls in  the trachieds of gymnosperms?
A) Xylan
64) Which chemical group chiefly constitutes cell walls?
A) Carbohydrates  (Polysaccharides)
65) What is a group of 100 glucose chains?
A) Micelle
66) What is a group of 20 micelles?
A) Microfibril
67) What is a group of 250 microfibrils?
A) Macrofibril
68) In which cell wall layer microfibrils are randomly arranged?
A) Primary wall
69) In which cell wall layer  microfibrils are parallelly  arranged?
A) Secondary wall
70) What is the matrix substance in middle lamella and cell walls?
A) Pectin
71) What is the most common hemicellulose in the primary cell wall?
A)  Xyloglucan
72) What is the most common hemicellulose in the primary cell wall of grasses?
A) Glucuron arabino xylan
73) What is the characteristic type of growth in cell walls?
A) Acid growth
74) Name the protein that catalyses the growth of cell walls.
A) Expansin
75) What is the permeability barrier over the epidermal cells exposed to atmosphere?
A) Cuticle
76) What are the chief components of cuticle?
A) Cutin & wax
77) What are the plant parts without cuticle?
A) Underground or submerged parts in water
78) What is the Intercellular cytoplasmic bridges between plant  cells?
A) Plasmodesmata
79) What is the extension of endoplasmic reticulum inside the plasmodesmata?
A) Desmotubule
80) What are the channels through which the protoplasts of all cells are interconnected to form a symplast?
A) Plasmodesmata
81) What are the interruptions on the surface of cell walls ?
A) Pits
82) What are the openings of plasmodesmata  on the surface of cell walls ?
A) Pits
83) What are the characteristic depressions on the surface of cell walls ? A) Pits
84) What are the parts of a pit pair?
A) pit opening,  pit cavity, pit membrane and middle lamella
85) What are the depression like pits on the primary cell wall?
A) Primary pit fields or primordial pits or primary pits
86) What kind of pit fields are found on primary walls of parenchyma?
A) Primary pit fields
87) What kind of pits are present between parenchyma  cells?
A) Simple pits
88) What kind of pits are present between tracheids or vessel elements?
A) Bordered pits
89) In which group of plants heterogeneous bordered pits are present?
A) Gymnosperms
90) What is the circular thickening at the centre of the middle lamella of a bordered pit in gymnosperms?
A) Torus
91) What is the membrane that covers the torus?
A)  Margo.
92) What kind of pits present  between parenchyma cells and tracheids or vessel elements?
A) Half-bordered pits
93) How are called the ladder like payttern of pit distribution on tracheary elements?
A) Scalariform pitting
94) What kind of pits have uniform diameter?
A) Simple pits
95) What kind of pits have non-uniform diameter?
A) Bordered pits
96) What kind of pits have an over-arche?
A) Bordered pits
97) What is the waxy layer on cell walls to reduce water loss?
A) Cuticle
98) Which is the chief part of the apoplast in plant tissues?
A) Cell wall
99) Which is the chief part of symplast in plant tissues?
A) Cytoplasm or Protoplasm
100) What is the deciding factor for a plant architecture? 
A) Cell wall
101) Which part of the plant cell provides roughages in human diet?
A) Cell wall
102) Which is the most abundant hemicellulose in plant cell walls?
A) Xyloglucan
103) Which component of the fruit cell walls gives consistency in making jams and jellies?
A) Pectin
104) What kind of chemical bonds lie between microfibrils in cell walls?
A) Hydrogen bonds
105) Which chemical substance provides tensile strength to bast fibres?
A) Lignin
106) Which is the major component of wood?
A) Secondary wall (Cellulose)
107) Which is the major component of biomass that can be converted into biofuels?
A) Secondary wall
108) What is the chief component of paper, cotton fibres and wood pulp?
A) Cellulose
109) Which cell wall layers are universal in all plant cells?
A) Middle lamella & primary wall only
110) Which adhesive organic substance joins plant cells?
A) Pectin
111) What is the  jelly like substance in ripened guava fruits?
A) Pectin
112) What are the fungi without cell walls in their vegetative structures but in reproductive structures?
A) Slime molds
113) Which group of algae provides agar-agar as solidifying agent in the microbial culture media?
A) Rhodophyceae  (Red algae)
114) Who discovered agar-agar?
A) Mino Tarozaemon
115) What is the polysaccharide from which agar is derived?
A) Agarose + Agaropectin
116) What are the two red algae from which commercial agar is extracted?
A) Gelidium and Gracilaria
117) What is the dry pulpy residue full of cell walls, which is left after the extraction of juice from sugar cane?
A) Bagasse

Saturday, 20 August 2016

CELL MEMBRANE (176 Qs)



All living cells in the world are surrounded by cell membrane. Neither animal nor plant cells are devoid of this. As Robertson says it is not only a unit membrane but also a universal membrane all around the cells and their organelles too.

Now read the following questions and answers and suggest some more questions for the aspirants for competitive exams. Please help us rectify the mistakes and improve the content.



QUESTIONS & ANSWERS

1) Which membrane protects the intracellular environment?
A) Cell membrane or plasma membrane or cytoplasmic membrane
2) Which is the outermost layer of animal cells?
A) Cell membrane
3) What is the gateway for the cell?
A) Cell membrane
4) Which is the security guard of the cell?
A) Cell membrane
5) What are the components of an endomembrane system?
A) Plasma membrane, endoplasmic reticulum (ER),  nuclear membrane, Golgi apparatus, and lysosomes.
6) What is the nature of biomembranes?
A) Quasi-fluid, selectively permeable membranes
7) Who coined the term cell membrane?
A) Nageli & Crammer
8) Who coined the term plasma membrane?
A) JQ Plowe
9) What is the thickness of a cell membrane?
A) 75-100 Angstroms
10) What are the extracellular structures that are in association with cell membrane?
A) Cell wall, glycocalyx, and cytoskeleton
11) Which is the Ectoplast?
A) Cell membrane
12) Where is periplasm present?
A) Between outer and inner membranes of bacteria
13) What is the chief component of outer membrane of bacteria?
A) Lipopolysaccharide
14) What is the chief component of all membranes?
A) Lipoproteins
15) What is the fundamental structure of the plasma membrane?
A) Phospholipid bilayer
16) What are the components of a phospholipid?
A) Glycerol, two fatty acid tails, and a phosphate head
17) What is the backbone of the membrane lipids?
A) Glycerol
18) Why is plasma membrane  amphipathic?
A) It contains both hydrophilic heads and hydrophobic tails
19) How many tails a phospholipid has?
A) 2 tails
20) What is the water loving end of a phospholipid?
A) Polar hydrophilic phosphate head
21) What is the water fearing end of a phospholipid?
A) Non-polar hydrophobic
fatty acid tails
22) Which component of the cell membrane is used for cell recognition and act as receptors and antigens?
A) Glycoprotein
23) Which component of a cell membrane maintains the fluidity of cell membranes?
A) Cholesterol
24) What are the lipids that provide stability and impermeability to plasma membranes?
A) Cholesterols
25) What kind of cells have cholesterol in their membranes?
A) Animal cells
26) How could the cell communicate with the external environment?
A)  Through receptor proteins,  hormones, neurotransmitters and signaling molecules.
27) What kind of proteins are transport proteins in cell membranes?
A) Globular proteins
28) What are the communication proteins in cell membranes?
A) Glycoproteins
29) What kind of organisms have multiple plasma membranes?
A) Prokaryotes
30) What is the reason for the flexibility of cell membranes?
A) Lipids
31) What are the double membranous organelles?
A) Nucleus,  mitochondria & plastids (chloroplasts)
32) What are the single membranous organelles?
A) Endoplasmic reticulum, Golgi apparatus,  Lysosomes,  microbodies,  vacuoles,  etc
33) How is the vacuolar membrane called?
A) Tonoplast
34) What is the maximum limit for optical microscopes?
A) 0.25 milli microns or 250 nano meter
35) What kind of structure is exhibited by plasma membrane under electron microscope?
A) Trilamellar structure
36) What is the major component of cell membranes?
A) Proteins
37) What kind of lipids are dominant in plasma membrane?
A) Phospholipids
38) Why are the biomembranes amphipathic?
A) Due to polar hydrophilic heads and nonpolar hydrophobic tails
39) What kind of carbohydrates are common in cell membranes?
A) Oligosaccharides
40) Who gave the lipid model of plasma membrane?
A) Overton
41) Who discovered the bilipid layer in plasma membrane?
A) Gorter & Grendel
42) Who gave the lamellar or sandwich model of plasma membrane?
A) Danielle and Davson
43) Who gave the unit membrane concept?
A) Robertson
44) Who gave the fluid mosaic model of plasma membrane?
A) Singer & Nicholson
45) Who described the cell membrane as "protein icebergs floating in a sea of lipids?"
A) Singer & Nicholson
46) What kind of proteins give elasticity and mechanical support to cell membrane?
A) Structural proteins
47) What are the three kinds of proteins as per their location in plasma membrane?
A) Extrinsic, intrinsic and transmembrane proteins
48) What are the proteins on the outer or inner surface of the plasma membrane?
A) Extrinsic or peripheral proteins
49) What are the proteins located inside the plasma membrane?
A) Inrinsic or integral proteins
50) What are the proteins that extend from outside to inside of the plasma membrane?
A) Transmembrane or tunnel proteins
51) What is the cause for the asymmetry of the plasma membrane?
A) Glycoproteins and glycolipids
52) What is the major driving forces in the formation of lipid bilayers?
A) Hydrophobic effect
53) What is the cell coat in some cells?
A) Glycocalyx
54) Who proved the fluidity of plasma membrane?
A) Frye & Edidin
55) How are the fused cells or cytoplasmic hybrids?
A) Cybrids
56) What are the "supra-membrane" structures?
A) Ascaveola, post-synaptic density, podosome, invadopodium, focal adhesion, and
cell junctions
57) What are the specific proteins that make supra-membrane structures?
A) Integrins and cadherins
58) What are the lipid vesicles?
A) Liposomes
59) What is the outermembrane of microvilli?
A) Glycocalyx
60) What are the plasma membrane evaginations or outpushings?
A) Microvilli, ciliary sheath, flagellar sheath, stereocilia
61) What are the plasma membrane invaginations or inpushings?
A) Pores, mesosomes,  lomasomes and transfer cells
62) What are the connections between two adjacent animal cells?
A) Junctional complexes
63) What are the cementing material between two adjacent animal cells?
A) Adherenes
64) What are the fusions between two adjacent animal cells?
A) Occludens
65) What is the spot where two adjacent animal cells join?
A) Macula
66) What is the strip along which two adjacent animal cells join?
A) Zonula
67) What are the intercellular junctional complexes between two plant cells?
A) Plasmodesmata
68) Who discovered plasmodesmata?
A) Strasburger
69) What are the cytoplasmic bridges between two adjacent plant cells?
A) Plasmodesmata
70) What are the plasma membrane invaginations to increase surface area for absorption?
A) Microvilli
71) What are the cell organelles that provide mechanical support to microvilli?
A) Microfilaments
72) Where do you find microvilli in human body?
A) Intestinal epithelium, liver cells, convoluted renal tubules, gall bladder, ureter.
73) What are the non-motile plasma membrane evaginations?
A) Stereocilia
74) Where do you find stereocilia in human body?
A) Epidydymus
75) What are the plasma membrane infoldings that help in replication and respiration in bacteria?
A) Mesosomes
76) What are the plasma membrane infoldings at the junction of two adjacent  eukaryotic cells?
A) Lomasomes
77) What are the fine hydrophilic channels between two adjacent animal cells?
A) Gap junctions
78) What are the plasma membrane evaginations that transfer stimuli between cells?
A) Intercellular bridges
79) What are formed when Intercellular outgrowth fit into one another?
A) Inter-digitations
80) What are the disc shaped thickened areas with tonofibrils between epithelial cells?
A) Desmosomes or Macular adherents
81) What are the desmosomes with microfilaments and intermediate filaments?
A) Terminal bars or Zonulae adherentes
82) What are the semi-disc shaped thickened areas with collagen fibrils between epithelial cells?
A) Hemidesmosomes
83) What are the impermeable fused areas between plasma membranes of adjacent cells?
A) Tight junctions or Zonulae occludentes
84) What is the energy free membrane transport?
A) Passive transport
85) What are the two types of passive transport?
A) Diffusion & osmosis
86) What is meant by membrane permeability?
A)  The rate of passive diffusion of molecules through the membrane
87) What are the molecules that pass through cell membranes due to diffusion?
A) Permeant molecules
88) Which two factors decide permeability of molecules through cell membranes?
A) Electric charge and polarity
89) How is described the movement of particles from their higher  to lower concentration?
A) Diffusion
90) What are membranous  proteins through which movement of water takes place?
A) Aquaporins
91) What is the movement of water from high concentrated to low concentrated solution across the semipermeable membrane?
A) Osmosis
92) Who discovered osmosis?
A) Jean-Antoine Nollet
93) What is the pressure that develops inside the cell due to the osmotic entry of water?
A) Osmotic pressure  (OP)
94) Which apparatus is used to measure osmotic pressure?
A) Osmometer
95) Who invented osmometer?
A) Pfeffer
96) What is the amount of osmotic pressure exerted by a solution?
A) Osmolariry or osmocity
97) What is the tension developed in a system when it is placed in a solution?
A) Tonocity
98) What are the three types of tonocity?
A) Hypotonic, hypertonic and isotonic
99) What kind of solution has low osmotic concentration or osmotic pressure?
A) Hypotonic solution
100) What kind of solution has high osmotic concentration or osmotic pressure?
A) Hypertonic solution
101) What kind of solution has similar osmotic concentration or osmotic pressure as that of the other?
A) Isotonic solution
102) What will happen when a cell is placed in a hypotonic solution?
A) Endosmosis
103) What will happen when a cell is placed in a hypertonic solution?
A) Exosmosis
104) What will happen when raisins are placed in water?
A) Swelling due to endosmosis
105) Which process keeps the plant cells turgid?
A) Endosmosis
106) What is the mechanism to prevent bursting of plant cells due to excess endosmosis?
A) Wall pressure
107) What is the reason for oozing out of water droplets from sliced cucumbers sprinkled with salt?
A) Exosmosis
108) What will happen when both turgor pressure and wall pressure become zero?
A) Plasmolysis
109) What is the process of shrinkage of protoplast from the cell wall?
A) Plasmolysis
110) What is the process of shrinkage of animal cell
A) Crenation
111) What is the first stage of plasmolysis when the protoplast is in still contact with cell wall at all places?
A) Limiting plasmolysis
112) What is the second stage of plasmolysis when the protoplast starts shrinking away from the corners of the cell wall?
A) Incipient plasmolysis
113) What is the unrecoverable stage of plasmolysis where the protoplast is in contact with cell wall only at a few places?
A) Evident plasmolysis
114) What is the reason for plasmolysis of plant cells or crenation of animal cells?
A) Exosmosis
115) What is the process of swelling of shrunken Protoplast in hypotonic solution?
A) Deplasmolysis
116) What are the different applications of plasmolysis?
A) Salt in pickles, sugar in jams, salting of fish, sprinkling salt on weeds, etc
117) Give examples for substances that show lipid matrix solubility and passive transport.
A) Triethyl citrate, ethyl alcohol,  methane
118) What are the passages in cell membranes through which the exchange of oxygen and carbon dioxide takes place?
A) Hydrophilic membrane channels  (tunnel proteins)
119) How is called the fine filtration from blood capillaries under pressure?
A) Ultrafiltration
120) What is the capillaries bunch in which the blood undergo ultrafiltration?
A) Glomerulus
121) Where does para-cellular ultrafiltration take place?
A) Gap junctions
122) Where does trans-cellular ultrafiltration take place?
A) Fenestrarions in cells
123) By which process waste products are removed from blood into isotonic solution?
A) Dialysis
124) What are the proteins that facilitate transport of substances across membranes without energy expenditure?
A) Permeases
125) How is called the occurrence of facilitated and active transport together?
A) Co-transport
126) Which is the downhill process in membrane transport?
A) Passive transport
127) Which is the uphill process in membrane transport?
A) Active transport
128) What kind of membrane transport occurs along concentration gradient?
A) Passive transport
129) What kind of membrane transport occurs against  concentration gradient?
A) Active transport
130) What kind of membrane transport requires energy?
A) Active transport
131) What are the integral proteins that helps active transport?
A) Carrier proteins
132) What is the difference between carrier proteins and permeases?
A) Carrier proteins require ATP but not permeases
133) What are pumps in cell membranes?
A) Active transport systems
135) What are the channels of active transport systems?
A) Gated channels
136) What is the driving force for ionic pumps in membranes?
A) ATP
137) How many Na ions are passed out and K ions pumped in when an ATP molecule is hydrolysed?
A) 3 Na ions & 2 K ions
138) Which ionic pump helps sea birds to excrete salts through their nasal glands?
A) Na-K pump
139) What are the types of secondary active transport?
A) Uniport, Cotransport (Symport) & Countertransport (Antiport)
140) What kind of pump transports only a single particle at a time?
A) Uniport
141) What kind of pumps transport two particles at a time?
A) Symport & Antiport
142) What kind of pump transports two particles at a time to the same side?
A) Symport
143) What kind of pump transports two particles at a time in opposite directions?
A) Antiport
144) What are the integral proteins meant for cotransport?
A) Symporters
145) Give an example for Symport.
A) Na out & Glucose in
146) Give an example for antiport.
A) Na out & Ca in
147) What is the movement of a large quantity of molecules across membranes at a time?
A) Bulk transport
148) What are the carriers of bulk transport?
A) Vesicles
149) What is the inward bulk transport?
A) Endocytosis
150) What is the outward bulk transport?
A) Exocytosis
151) What is cell drinking?
A) Pinocytosis
152) Who discovered pinocytosis?
A) Lewis
153) Name the fibrillar protein required for pinocytosis?
A) Clathrin
154) Name the Contractile protein required for pinocytosis?
A) Actin
155) What are the pinocytotic vesicles?
A) Pinosomes
156) Which vesicle of golgi apparatus absorbs a pinosome content?
A) Receptosome
157) What is cell eating?
A) Phagocytosis
158) What are the phagocytic blood cells?
A) Leucocytes (WBC)
159) What are the phagocytic liver cells?
A) Kupffer's cells
160) What are the phagocytic spleen cells?
A) Reticular cells
161) What are the phagocytic cells of connective tissue?
A) Histiocytes
162) What is the phagocytic vesicle?
A) Phagosome
163) Which cell organelle form a digestive vacuole from pinosomes or phagosomes?
A) Lysosome
164) What is the process of removal of undigested food from cell?
A) Ephagy (Exocytosis)
165) What are the membranous locomotory organelles?
A) Pseudopodia & undulations
166) What are the pseudopodial cells?
A) Amoeba, WBC, macrophages
167) What are the contractile proteins involved in pseudopodia formation?
A) Actin-myosin
168) In what kind of cells locomotory membranous undulations are seen?
A) Fibroblasts
169) Whether the bulk transport is an active or passive process ?
A) Active process
170) Where are antigens located?
A) Surface of cell membrane
171) What is the cell membrane of myocytes?
A) Sarcolemma
172) What is the cell membrane of oocytes?
A) Oolemma
173) What is the cell membrane of axons of neurons?
A) Axolemma
174) What is a hollow droplet of bilayer membrane?
A) Liposome
175) Which is the energized membrane transport?
A) Active transport
176) What are the transport pumps in guard cells of stomata?
A) K-H pumps

Friday, 19 August 2016

PROTOPLASM & CYTOPLASM (76 Qs)


Protoplasm is living substance which is present in all living cells except viruses. The life and death of a cell or an organisms is exclusively depends on the condition of protoplasm. Coagulated or denatured protoplasm indicates death of that particular cell or an organism.

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QUESTIONS & ANSWERS

1) Which is the living substance?
A) Protoplasm
2) Which is the fundamental matter out of which all living organisms are made?
A) Protoplasm
3) Who coined the term protoplasm for the substance in an animal embryo?
A) Purkinje
4) Which is the physical basis of life?
A) Protoplasm
5) Who called protoplasm as physical basis of life?
A) Thomas Huxley
6) What kind of organisms do not have protoplasm?
A) Viruses
7) According to whom cytoplasm is nothing but protoplasm?
A) Mohl
8) According to whom  cytoplasm plus nucleoplasm is protoplasm?
A) Strasburger
9) Which is the major component of protoplasm?
A) Water
10) Which is the major organic substance in protoplasm?
A) Proteins
11) What are the major inorganic elements in protoplasm?
A) Carbon, Hydrogen,  Oxygen and Nitrogen
12) What is protoplasm without cell membrane?
A) Protoplast
13) How is called protoplasm between cell membrane and nucleus?
A) Cytoplasm
14) What is protoplasm without nucleus and vacuoles?
A) Cytoplasm
15) What is peripheral protoplasm around a big vacuole in a mature plant cell?
A) Primordial Utricle
16) Which part of the cell behaves like glass?
A) Cytoplasm
17) Who coined the term  cytoplasm?
A) Kolliker
18) How is called the protoplasm inside the nucleus?
A) Nucleoplasm
19) What kind of organisms do not have nucleoplasm?
A) Prokaryotes
20) Who coined the term nucleoplasm?
A) Van Beneden
21) What is chromatoplasm?
A) Plastids
22) What is cytoplasm without organelles and inclusions?
A) Cytosol, hyaloplasm, kinoplasm or cytoplasmic matrix
23) What is the outer gel like cytoplasm?
A) Ectoplast, Ectoplasm or Plasmal gel
24) What is the inner sol part of cytoplasm?
A) Endoplast, Ectoplasm or Plasma Sol
25) What is the cell cortex?
A) Ectoplasm
26) How is called the perpetual motion of endoplasm?
A) Cyclosis or cytoplasmic or protoplamic  streaming
27) What are the two types of cyclosis?
A) Rotation and circulation
28) How is called the unidirectional flow of cytoplasm?
A) Rotation
29) How is called the flow of cytoplasm in different directions?
A) Circulation
30) What are the membranous structures in cytoplasm?
A) Organelles
31) What are the double membranous organelles in the cell?
A) Nucleus,  mitochondria and plastids  (chloroplasts)
32) What are the single membranous organelles in the cell?
A) Endoplasmic reticulum,  Golgi apparatus,  Lysosomes,  Peroxisomes,  Glyoxysomes,  Sphaerosomes, Vacuoles, etc
33) What are the non-membranous organelles in the cell?
A) Ribosomes,  Nucleolus
34) Which major metabolic activity does occur in cytosol?
A) Glycolysis
35) Which is the extra-cytoplasmic organelle?
A) Nucleus
36) What are the metabolically  inactive byproducts in cytoplasm?
A) Deuteroplasts or organic inclusions
37) What are the crystalline inclusions in cytoplasm?
A) Calcium oxalate & Silicon dioxide
38) What is the storage inclusion in animal cells?
A) Glycogen
39) What is the storage inclusion in plant cells?
A) Starch
40) What are the cells with abundant fats?
A) Adipocytes
41) What is the living part of the protoplasm?
A) Bioplasm
42) What is the non-living part of the protoplasm?
A) Ergastic substances
43) What are the different ergastic substances?
A) Crystals, oil drops, gums, tannins, resins, etc.
44) What are the main ergastic substances of plant cells?
A) Cellulose and starch
45) What is the chief substance in cell walls?
A) Cellulose
46) What are the different protective layers in or on the cell wall?
A) Waxes, suberin, and cutin
47) What is a group of calcium oxalate crystals in plant cells?
A) Druse
48) What are the needle like crystals of calcium oxalate bundles in  a plant cell?
A) Raphides
49) What are the calcium carbonate bunches in rubber plant cells?
A) Cystoliths
50) What are the cells with cystoliths?
A) Lithocysts
51) Who called protoplasm as sarcode?
A) Felix Dujardin
52) Who gave the protoplasm theory?
A) Max Schultz
53) What is the physical nature of protoplasm?
A) Multiphased complex system
54) What is the basis for colloidal nature of cytoplasm?
A) Organic solutes such as glucose, fatty acids, amino acids, minerals, vitamins, hormones and enzymes.
55) Who gave the  granular theory of protoplasm?
A) Altmann
56) Who gave the alveolar theory of protoplasm?
A) Butchlli
57) Who gave the fibrillar theory of protoplasm?
A) Flemming
58) Who gave the reticular  theory of protoplasm?
A) Klein, Comoy
59) What is the process of conversion of cytoplasm from gel into sol state?
A) Solation
60) What is the process of conversion of cytoplasm from sol into gell state?
A) Gelation
61) What is the zigzag  motion of colloidal particles in cytoplasm?
A) Brownian movement
62) What is the physical nature of Protoplasm?
A) Optically homogenous, elastic, colourless, jelly like, semi-transparent to transparent and semi-viscous substance.
64) What is protoplasmic response to stimulus?
A) Irritability
65) Who explained the colloidal structure of protoplasm?
A) Fisher and Hardy
66) What kind of cytoplasmic movement is distinct in the cells of  Hydrilla and  Vallisneria?
A) Rotation
67) What kind of cytoplasmic movement is seen in staminal hairs of Tradescantia?
A) Circulation
68) What kind of chemical forces bind protoplasmic particles?
A) Vanderwaal’s forces
69) What is the fundamental basis for mechanical behaviour of cytoplasm?
A) Gel state
70) What will happen to the electrocuted protoplasm?
A) Denaturation (Coagulation)
71) What is the pH of cytoplasm?
A) 7.0 - 7.4
72) What is the major part of intracellular fluid?
A) Cytosol
73) What is the liquid part of the cytoplasm?
A) Cytosol
74) Who coined the term Cytosol?
A) H. A. Lardy
75) In what kind of cells cell sap is the main component; not cytoplasm?
A) Plant cells
76) Which organelle divides the cytoplasm into different compartments?
A) Endoplasmic Reticulum

Thursday, 18 August 2016

NUCLEUS (100 Qs)



The central head office of any eukaryotic cell is the nucleus. Well organised nucleus with chromatin reticulum or chromosomes is the characteristic feature of eukaryotic cells, the feature that is lacking in prokaryotes.

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QUESTIONS & ANSWERS

1) Who discovered nucleus?
A) Robert Brown
2) Who proved nucleus as a storehouse of hereditary information?
A) Hammerling
3) What was the experimental organism of Hammerling?
A) Acetabularia
4) What is Acetabularia?
A) A green marine alga
5) How do you call a cell with a single nucleus?
A) Monokaryotic cell
6) Which group of fungi show dikaryotic mycelia?
A) Basidiomycetes
7) What are the anucleate cells in the human body?
A) RBCs
8) What are the anucleate cells in plants?
A) Sieve tubes
9) Which species of paramecium is binucleate?
A) Paramecium caudatum
10) Which species of paramecium is trinucleate?
A) Paramecium aurelia
11) How is called the multinucleate body of slimemolds?
A) Plasmodium
12) What is a multinucleate animal cell?
A) Syncitium
13) What is a multinucleate plant cell?
A) Coenocyte
14) Which is the largest cell component in an animal cell?
A) Nucleus
15) Which is the largest cell component in a mature plant cell?
A) Vacuole
16) Which is the master organelle?
A) Nucleus
17) Which is the biggest component of a nucleus?
A) Non-basic proteins
18) What is biggest component of a nucleus?
A) Proteins
19) What is meant by karyon?
A) Nucleus
20) What is meant by a Karyotype?
A) a total set of chromosomes in a nuu
21) What is meant by karyotheca?
A) Nuclear Envelope
22) What is the space between two nuclear membranes?
A) Perinuclear space
23) What are the associated structures of nuclear envelope?
A) Rough Endoplasmic Reticulum & Ribosomes
24) Which part of the nucleus contain parts like diaphragm, depraved, annuli, blebs and micropore?
A) Nuclear pore
25) What is the facilitator of substances through a nuclear pore?
A) Nucleoporins
26) What is the colloidal fluid inside the nucleus?
A) Nucleoplasm or nuclear sap
27) What meant by karyolymph?
A) Nucleoplasm or nuclear sap
28) What are the chief enzymes of nucleoplasm?
A) DNA polymerase,  nucleosidase, phosphorylase, ribonuclear synthetase, nucleotide synthetase
29) How is called the proteinaceous fibrillar layer inner to inner nuclear membrane?
A) Nuclear lamina
30) What are the proteins of nuclear lamina?
A) Lamins
31) What is the maintainer of nuclear shape?
A) Nuclear lamina
32) Who discovered nuclear lamina?
A) Harris & James
33) What is the  fibrillar network spread all over the nucleus?
A) Chromatin reticulum
34) Who discovered chromatin?
A) Flemming
35) What is the chemical nature of chromatin?
A) DNA-Histone complex
36) What is the loosely coiled, lightly stained, active part of chromatin?
A) Euchromatin
37) What is the highly coiled, darkly  stained, inactive part of chromatin?
A) Heterochromatin
38) Who was the first to differentiate euchromatin & heterochromatin?
A) Heitz
39) What are the large granular parts of heterochromatin?
A) Karyosomes
40) What kind of heterochromatin is universal?
A) Constitutive heterochromatin
41) What kind of chromatin is formed only to inactivate certain genes?
A) Facultative heterochromatin?
42) What is the Barr body in oocytes of human beings?
A) Facultative heterochromatin
43) What is the core of the nucleosome?
A) Octomer of 8 Histones
44) What are the nucleosomal histones?
A) H2A, H2B, H3 & H4
45) How many DNA base pairs comprise a nucleosome?
A) 200
46) What is the connecting link between two Nucleosomes?
A) Linker DNA
47) What is the folded nucleosome chains?
A) Chromatin
48) What is the folded chromatin?
A) Chromosome
49) What is the spherical non-membranous structure in the nucleus?
A) Nucleolus
50) Who discovered nucleolus?
A) Fontana
51) Who coined the term nucleolus?
A) Bowman
52) What is NOR?
A) Nucleolar Organiser Region
53) Where is the nucleolus attached to the chromatin?
A) NOR
54) What are fibrils in a nucleolus?
A) RNAs
55) What is the amorphous portion of the nucleolus?
A) Parse Granulosa
56) What is the fibrillar portion of the nucleolus?
A) Parse Fibrosa
57) Which kind of ribosomes are formed in nucleolus?
A) tRNA
58) Which is the ribosomal factory?
A) Nucleolus
59) What is the compacted DNA structure in a prokaryotic cell?
A) Genophore or nucleiod
60) What are replaced by histones in prokaryotic DNA packing?
A) Polyamines
66) Which part of the cell controls the gene expression?
A) Nucleus
67) What is the mechanical support to the nucleus?
A) Nuclear lamina
68) Where is the assembly of ribosomes taken place?
A) Nucleolus
69) What is the first organelle to be discovered?
A) Nucleus
70) Who was Robert Brown?
A) Scottish botanist
71) In what kind of plants Robert Brown discovered the nucleus?
A) Orchids
72) Who called the nucleus as cytoblast?
A) Matthias Schleiden
73) What percentage of a mammalian cell is the nucleus?
A) 10%
74) Which part of the nuclear pore extends into the Nucleolplasm?
A) Nuclear basket
75) What are the transporting factors in nuclear pores?
A) Karyopherins
76) What kind of karyopherins mediate the movement of substances into the nucleus?
A) Importins
77) What kind of karyopherins mediate the movement of substances out of the nucleus?
A) Exportins
78) What are the two kinds of lemins on outer surface of nuclear lamina?
A)  Emerin and Nesprin
79) Which nuclear protein deficiency causes pre-mature ageing in human beings?
A) Lemin
80) What is the average length of a nuclear DNA in human cells?
A) 2M
81) Where is extranuclear DNA is present in animal cells?
A) Mitochondria
82) What kind of chromatin is present in centromeres and telocentres?
A) Heterochromatin
83) What is the suborganelle of the nucleus?
A) Nucleolus
84) What are the largest structures transported through nuclear pores?
A) Ribosomal Subunits
85) Where are Cajal bodies, Gemini bodies, PIKA, PML bodies, para-speckles, and splicing-speckles present?
A) Nucleus
86) Which is the dynamic centre of the cell?
A) Nucleus
87) What is the first step in gene expression?
A) Transcription of RNA from DNA
88) Which is the site of replication and transcription?
A) Nucleus
89) Which is the site of translation?
A) Ribosomes
90) Which enzyme unwinds the double-stranded DNA molecule?
A) Helicase
91) Which enzyme  synthesizes the  RNA molecule?
A) RNA polymerase
92) What is  the function of Ran-GTP nuclear transport cycle?
A) Transport of RNA and proteins across nuclear membranes
93) What is the process of programmed cell death?
A) Apoptosis
94) What is the end of the prophase of mitosis?
A) Dissolution of nuclear envelope
95) In what kind of mitosis the nuclear envelope remains intact?
A) Closed mitosis
96) In what kind of mitosis the nuclear envelope is dissolved?
A) Open mitosis
97) What kind of centrosomes lead to closed mitosis?
A) Intranuclear centrosomes
98) What are the different organisms exhibiting closed mitosis?
A) Dinoflgeates, ciliates, sporozoans, yeasts, fungi, etc
99) Name the intestinal parasite with binucleate conditions?
A) Giardia
100) What are the syncitial or multinucleate cells in human beings?
A) Myocytes (muscle fibrils)