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Question
State how does meiosis maintains chromosome number in a species.
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Solution
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.
RELATED QUESTIONS
The term “chromosomes” literally means ______.
Mention the contribution of the scientist given below in the study of chromosome:
Balbiani
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Name the following:
The part of the cell associated with heredity.
Complete the following sentence with appropriate word :
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Name the following:
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Complete the following sentence with appropriate word:
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Multiple Choice Question
Chromosomal aberrations are caused by:
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Define euploidy.
Match the following.
| 1. Autosomes | - | Trisomy 21 |
| 2. Diploid condition | - | 9 : 3 : 3 : 1 |
| 3. Allosome | - | 22 pair of chromosome |
| 4. Down’s syndrome | - | 2n |
| 5. Dihybrid ratio | - | 23rd pair of chromosome |
______ is a sudden permanent heritable change that can occur in the gene, in the chromosome or chromosome number.
What' does 'P' and 'Q' represent in the following diagram of X and Y chromosomes? Select the correct option representing, its appropriate description.
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Differentiate between X-chromosome and Y-chromosome with reference to –
- length of non-homologous regions
- type as per the position of the centromere
After a mitotic cell division, a human female cell will have ______.
Which of the following describes the correct type of chromosome?
X- chromosome: A : : Y-chromosome: В
