NUCLEIC ACIDS AND CELL DIVISION

1	[A]: DNA and RNA are acidic in nature [R]: They have pentose sugars Both A and R are true and R is the correct explanation of A Both A and R are true but R is not the correct explanation of A A is true but R is false A is false but R is true Ans:Both A and R are true but R is not the correct explanation of A
2	The nitrogen base Cytosine is Monocyclic, Homocyclic Dicyclic, Heterocyclic Monocyclic, Heterocyclic Dicyclic, Homocyclic Ans:Monocyclic, Heterocyclic
3	In a given nucleotide Phosphate is attached to 1st position of Nitrogen base and Nitrogen base is attached to 1st carbon of sugar Phosphate is attached to 2nd Carbon and Nitrogen base to the 1st carbon of the pentose sugar Uracil is attached to 1st Carbon of Deoxyribose and phosphate to the 5th carbon of the sugar Phosphate is attached to 5th carbon and Nitrogen base to the 1st carbon of Pentose sugar Ans:Phosphate is attached to 5th carbon and Nitrogen base to the 1st carbon of Pentose sugar
4	These components of DNA are 5-Carbon substances I. Sugar II. Adenine III. Guanine IV. Cytosine V. Thymine All except V All except II All except IV All except III Ans:All except IV
5	DNA replication is initiated with the catalytic activity of DNA polymerase DNA ligase Topoisomerase Helicase Ans:Helicase
6	A given DNA has 4 spirals with the following condition in its different spirals I. A spiral with 28 hydrogen bonds II. A spiral with 6 Guanine bases III. Spiral with 25 hydrogen bonds IV. Spiral with 6 Adenine bases Arrange the above 4 different spirals in a sequence of gradual increase in the number of methylated nitrogen bases I, II, III, IV I, III, II, IV IV, II, III, I III, II, IV, I Ans:I, II, III, IV
7	In a B-DNA molecule, there are 300 hydrogen bonds, These hydrogen bonds are formed in 3:2 ratio between GC and AT. Then the ratio between number of Adenine and Cytosine bases in the DNA is 3:2 2:3 3:4 1:1 Ans:1:1
8	The most common nitrogen base seen in various non-sense codons and initiating codons is Adenine Guanine Uracil Cytosine Ans:Uracil
9	Match the following A -V, B - I, C - IV, D - III A - V, B - II, C - III, D - IV A - V, B - I, C- II, D - III A - IV, B - I, C - II, D - III Ans:A - V, B - I, C- II, D - III
10	Study the following table and choose the correct combination I and II II and III III and IV I and IV Ans:II and III
11	Guanine and Cytosine exist in 1:1 ratio but not Adenine and Thymine in M 13 virus mRNA tRNA Reovirus Ans:Reovirus
12	The following nucleic acid always ends with Adenine nucleotide mRNA tRNA rRNA DNA Ans:tRNA
13	rRNA is mainly transcribed on the DNA of chromosomes which must have Secondary constriction II Secondary constriction I Telocentric condition Isobrachial chromosomes Ans:Secondary constriction I
14	Cell inheritance theory was proposed by Schleiden Schwann Flemming Virchow Ans:Virchow
15	[A]: During G1 stage of Cell Cycle, the cell is metabolically inactive [R]: DNA replication does not occur during the period between M and S stages Both A and R are true and R is the correct explanation of A Both A and R are true but R is not the correct explanation of A A is true but R is false A is false but R is true Ans: A is false but R is true
16	Arrange the following cells of an angiosperm in a sequence of gradual increase in the amount of DNA I. Primary endosperm nucleus in G1 stage II. Stem apical meristem cell in Prophase III. Generative cell in G2 stage III. Polar nucleus III, IV, I, II IV, III, I, II IV, III, II, I IV, I, III, II Ans:IV, III, I, II
17	If the amount of DNA and number of chromosomes in a cell nucleus are respectively 2C and 2n, then the amount of DNA and number of chromosomes in the cell during G2 stage would be respectively 4C, 4n 2C, 2n 4C, 2n 2C, 4n Ans:4C, 2n
18	There is no S stage in the interphase present between two mitotic divisions a mitotic and meiotic division 1-celled and 2-celled stage of microspore Meiosis I and Meiosis II Ans:Meiosis I and Meiosis II
19	The ATP formed in G2 stage of cell cycle are mainly used for I. Organisation of nuclear envelope II. Organisation of Spindle III. Movement of chromosomes IV. Cohesion of sister chromatids I and II III and IV II and III I, II, III Ans:II and III
20	There is increase in the number of all cell organelles in G2 stage except Power house of the cell The cell organelle with linear DNA cell organelle with circular DNA Palade granules Ans:The cell organelle with linear DNA
21	In a Dicot plant growth divisions occur in I. Vascular cambium II. Cork cambium III. Procambium IV. Intercalary meristem I and II only II, III, IV only I, II, IV only I, II,III, IV Ans:I, II,III, IV
22	[A]: Chromosomal size is determined in Metaphse [R]: The chromatids of chromosomes are clearly seen in Prophase Both A and R are true and R is the correct explanation of A Both A and R are true but R is not the correct explanation of A A is true but R is false A is false but R is true Ans:Both A and R are true but R is not the correct explanation of A
23	Mitosis in plants was discovered by a person who also discovered Double fertilization Embryosac and embryo Embryosac and Syngamy Chalazogamy and Syngamy Ans:Embryosac and Syngamy
24	Arrange the following events of cell cycle in Correct sequence I. Visibility of 2 chromatids of chromosomes II. Replication of DNA III. Attachment of spindle fibres to Kinetochores IV. Disruption of Nuclear envelope II, I, IV, III I, II, IV, III III, IV, I, II II, I, III, IV Ans:II, I, IV, III
25	Chromosomes do not show any movement at Mid prophase Late Prophase Metaphase Late Metaphase Ans:Late Metaphase
26	The total number of chromosomal fibres that can be seen in metaphasic metacentric cells of Gossypium is 96 52 104 26 Ans:104
27	The total number of chromosomes seen in mid-anaphase of a meristematic cell of Oryza is 24 48 96 72 Ans:48
28	[A]:During mitotic anaphase, the chromosomes are divided into two daughter chromosomes due to pull mechanism [R]: In the third stage of Karyokinesis, the continuous spindle fibres play a major role in dragging the chromosomes to respective poles Both A and R are true and R is the correct explanation of A Both A and R are true but R is not the correct explanation of A A is true but R is false A is false but R is true Ans:A is true but R is false
29	Chromosomal identity of chromatin is lost during Anaphase Cell plate formation Cytokinesis Telophase Ans:Telophase
30	The ratio between number of chromatids, telomeres, chromosomal arms and kinetochores of a metacentric chromosome of mitotic anaphase is 1:2:2:2 2:2:2:1 1:2:2:1 1:1:2:2 Ans:1:2:2:1
31	Phragmoplast is made of Golgi vesicles Golgi vacuoles Endoplasmic reticulum Microtubules Ans:Microtubules
32	Arrange the following events of Mitotic karyokinesis in sequence I. Total disappearance of Kinetochore spindle fibres II. Phragmoplast organization III. Division of centromere IV. Cell plate formation III, I, IV, II I, III, II, IV II, IV, I, III III, I, II, IV Ans:III, I, II, IV
33	How many mitotic divisions have to occur for the formation of 2000 cells from 50 cells 1999 1000 1500 1950 Ans:1950
34	A meristem has 200 cells. Upon every generation of divisions in the tissue 25% of cells show differentiation. After 3 generations of divisions in the meristem, what is the total number of cells formed. 1600 1150 1200 1050 Ans:1150
35	This is not the significance of mitosis Helping in asexual reproduction Conserving the genetic integrity of an organism Involving in wound healing Exchang of genetic material between sister chromatids Ans:Exchang of genetic material between sister chromatids
36	Mitotic divisions are not shown by Cells of Spiriogyra filament Zygospore of Spirogyra Zygote of Funaria Embryo of angiosperms Ans:Zygospore of Spirogyra
37	Plasmosomes are organized during Anaphase Cytokinesis Cell plate formation Phase reversal to Prophase Ans:Phase reversal to Prophase
38	Cytokinesis of plants is best described as Centripetal, Furrow method Centrifugal, furrow method Centripetal, Cell plate method Centrifugal, Cell plate method Ans:Centrifugal, Cell plate method
39	Match the following A- II, B - IV, C - I, D - III A - II, B - IV, C-III D - I A - IV, B - II, C - I, D-III A - II B - I, C - IV, D - III Ans:A- II, B - IV, C - I, D - III
40	If the amount of DNA in a Meiocyte in G1 stage is 2C, the amount of DNA in the nucleus of Telophase I is 2C C 4C ½ C Ans:2C
41	Separation of a homologues of a bivalent during Meiosis is initiated at Pachytene Diakinesis Diplotene Metaphase I Ans:Diplotene
42	Sister chromatids of Chromosomes are always genetically identical in I. Zygotene II. Diplotene III. Metaphase IV. Metaphase I only III I and II III and IV I and III Ans:I and III
43	The principle of the following meiotic event is exploited in genetic engineering Synapsis Congression Disjunction Crossing over Ans:Crossing over
44	The ratio between the number of nuclear envelops disappeared to the total number new nuclear envelops formed in a meiotic division is 1:4 3:4 1:1 1:2 Ans:1:2
45	Chromosomes move as Bivalents in I. Anaphase I II. Diakenesis III. Anaphase II IV. Metaphase I and II II and IV III and IV I and III Ans:II and IV
46	Polypeptides play a role during I. Synapsis II. Crossing Over III. Disjunction I only I and II II and III I, II, III Ans:I, II, III
47	[A]: The number of crossing overs in a bivalent are easily counted in Diplotene [R]: Synaptonemal complex is dissolved in a stage of Meiosis interpolated between Pachytene and Diakinesis Both A and R are true and R is the correct explanation of A Both A and R are true but R is not the correct explanation of A A is true but R is false A is false but R is true Ans:Both A and R are true and R is the correct explanation of A
48	Stage of Prophase I with high intensity of Chromosomal condensation is Zygotene Pachytene Diplotene Leptotene Ans:Diplotene
49	Arrange the following events of Meiosis I in correct sequence I. Increase in the length of Chromosomes II. Increase in the size of Nucleus III. Increase in the size of Cell IV. Increase in the size of Nucleolus III, II, IV, I II, III, IV, I I, IV, II, III III, II, I, IV Ans:III, II, IV, I