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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 151. |
What is the difference between mitosis and meiosis? |
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| 152. |
Distinguish between mitosis and meiosis. |
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| 153. |
What is the importance of meiosis in creating variations ? |
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Answer» During meiosis, the exchange of chromosomal material takes place between the non-sister chromatids forming new combinations. These new combinations give rise to variations which result in the evolution of species and even in the origin of new species. |
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| 154. |
After meiosis I, the resultant daughter cells have (A) four times the amount of DNA in comparison to haploid gamete. (B) same amount of DNA as in the parent cell in S phase. (C) twice the amount of DNA in comparison to haploid gamete. (D) same amount of DNA in comparison to haploid gamete. |
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Answer» (C) twice the amount of DNA in comparison to haploid gamete. |
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| 155. |
Mitosis differs from meiosis in not having (A) Long prophase (B) duplication of DNA (C) Synapsis and crossing over (D) interphase |
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Answer» The correct answer is (C) Synapsis and crossing over |
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| 156. |
State how does meiosis maintain chromosome number in a species. |
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Answer» The gametes are formed by meiosis. During meiosis the number of chromosomes is reduced to half i.e. the gametes contain haploid number of chromosomes. The male and female gametes fuse to form a diploid zygote. In this way meiosis maintains chromosome number in a species. |
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| 157. |
How prophase-I of meiosis differs from prophase of mitosis in an essential way? Describe how it affects the daughter cells ? |
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Answer» Prophase-I of meiosis has five sub-stages namely Leptotene, Zygotene, Pachytene, Diplotene and Diakinesis. In pachytene exchange of genetic material between non-sister chromatids takes place through crossing over and chiasma formation which does not occur in prophase of mitosis. As a result, the daughter cells have a variation in their genetic composition contrary to identical daughter cells of mitosis. |
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| 158. |
What is the importance of meiosis? |
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Answer» The meiosis is important to maintain the constant number of chromosomes in a species. It also brings about variations which result in the evolution or origin of new species. |
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| 159. |
What is the importance of chiasma formation ? |
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Answer» Chiasma is the region where crossing-over takes place. By the formation of chiasma, exchange of genetic material between non-sister chromatids of the homologous chromosomes is accomplished. So, chiasma is the means of bringing about recombination of characters and thus variations in multicellular organisms. |
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| 160. |
What is exact structure of synaptonemal complex? |
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Answer» Synaptonemal complexes are zipper like structures assembled between homologous chromosomes during the prophase of first meiotic division. |
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| 161. |
What is structure of chiasma? |
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Answer» Chiasma is a X-shaped point of attachment between two non-sister chromatids of a homologous chromosomes. |
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| 162. |
Which type of proteins are involved in formation of spindle fibres? |
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Answer» Spindle fibres are formed from microtubules with many accessory proteins. |
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| 163. |
Colchicine is an alkaloid extracted from plants. It prevents the formation of spindle fibres. In the presence colchicine, if a cell enters mitosis what would be the outcome? |
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Answer» The spindle fibres are necessary for segregating the sister chromatids to opposite poles of the cell during anaphase. In the presence of colchicine, no spindle fibres will form to attach to the kinetochores (small disc¬like structures present on chromosomes). Therefore, the cell will be stuck in mitosis with the condensed pairs of sister chromatids in an unorganized array. |
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