Total number of autosomes will be the same in:
I. | Male and female humans |
II. | Male and female birds |
III. | Male and female Drosophila |
IV. | Male and female grasshopper |
1. | Only I, II, and III | 2. | Only I, II, and IV |
3. | Only II, III, and IV | 4. | I, II, III, and IV |
Select the incorrect statement:
1. | Human males have one of their sex-chromosome much shorter than the other. |
2. | Male fruit fly is heterogametic. |
3. | In male grasshoppers, 50% of sperms have no sex chromosome. |
4. | In domesticated fowls, the sex of progeny depends on the type of sperm rather than the egg. |
Consider the following statements regarding
Y chromosome in humans:
I. | Y chromosome is a male-determining chromosome in humans |
II. | Y chromosome contains a gene, SRY, which triggers embryonic development as a male |
III. | 50 % of sons of a male inherit his Y chromosome |
Of the given statements, the correct statements are:
1. | I and II only | 2. | I and III only |
3. | II and III only | 4. | I, II, and III |
A woman receives her X chromosomes from:
1. her mother only
2. her father only
3. both her mother and her father
4. extranuclear DNA in her mother's egg
The sex of the fetus is determined:
1. | at the time of fertilization by the type of sperm fertilizing the ovum. |
2. | at the time of fertilization by the female parent as she always produces an egg with an X chromosome. |
3. | at the time of implantation due to the secretion of TDF by the fetal testes. |
4. | at the time of implantation due to the secretion of ODF by the fetal testes. |
Identify the incorrect statement regarding the various methods of sex determination in living organisms:
1. | A male grasshopper has an odd number of chromosomes in its somatic cells. |
2. | A person with Klinefelter syndrome will be genotypically female. |
3. | In butterflies the female flies are diploid while the male flies are haploid. |
4. | A fruit fly with two X chromosomes and two sets of autosomes will be a fertile female. |
A woman has four daughters. The chance that her next child will be a son is:
1. | 1 | 2. | 0 |
3. | \(1 \over 2\) | 4. | \(1 \over 4\) |
In a certain taxon of insects, some have 17 chromosomes and others have 18 chromosomes. The 17 and 18 chromosome-bearing organisms are:
1. males and females, respectively
2. females and males, respectively
3. all males
4. all females
1. | 2. | ||
3. | |
4. | |