Related Questions

Consider the following statements.
1. Allosomes, i.e. chromosomes which are responsible for determination of sex e.g. X and Y chromosomes.
2. Autosomes, i.e. chromosomes, which determine the somatic characters.
Which of the statement(s) given above is/are true?
Consider the following statements.
1. Human beings have 23 pairs of chromosomes.
2. Sex chromosome in human male are named XY.
3. Chromosomes are best seen in metaphase.
Which of the statements given above is/are false about chromosomes?
Assertion (A) Human beings have 23 pair of chromosomes, one of which is the sex chromosomes and the remaining are 22 autosomes. The X-linked disease are related to mutation on a sex chromosomes.
Reason (R) Colour blindness results from a mutation in X-chromosome.
Of the two diploid species, species I has 36 chromosomes and species II has 28 chromosomes. How many chromosomes would be found in an allotriploid individual?
Consider the following statements regarding supernumerary chromosomes and choose the correct answer:
1. They are not homologous with any of the normal chromosomes
2. They form synapses among themselves
3. They are generally smaller than normal chromosomes
4. They are found more commonly in plants than in animals
Temperature-sensitive mutants can not replicate their chromosomes at non-permissive temperatures.
Consider the following statements regarding the pachytene substage of prophase I during meiosis and choose the correct answer:
1. Pachytene is said to begin when synapsis is completed
2. During pachytene the chromosomes are associated in bivalents or tetrads
3. Shortening and thickening of the chromosomes takes place due to longitudinal contraction
4. Exchange of groups of genes takes place as a result of crossing over
The 0.3% of DNA does not replicate during the S phase. This DNA replication occurs in
Consider the following statements with regard to the functions of the centromere in the chromosome.
1. Centromeres are the centres of movement of the chromatids or chromosomes during anaphase separation.
2. Acentric chromosomes lack the capacity to segregate in a regular fashion.
3. Crosing-over in one arm of a metacentric chromosome does not affect the crossing over in the arm of the same chromosome.
Which of the statements given above are correct?
Certain segments of the chromosomes, or the entire chromosomes, are more condensed than the rest of the karyotype during various stages of the cell cycle. Such difference in thickening has been called