Sex Determination in Humans

Q.

In human beings, sex of an individual is determined:

1. During the initial stages of pregnancy

2. During the later stages of pregnancy

3. By the environmental factors

4. At the time of fertilization

Q.

An egg usually has X chromosome, but in some cases it can have Y chromosome.

1. True

2. False

Q.

Why are the chances of an offspring being male or female always 50:50?

1. The movement of sperm is random.

2. Equal number of X and Y bearing sperms are released.

3. The egg has no particular affinity towards a X bearing sperm or a Y bearing sperm

4. None of the above

Q. A couple has 6 children, of which 5 are girls and 1 is a boy. The probability (in percentage) of having a girl next, is

1. $10\%$
2. $20\%$
3. $50\%$
4. $100\%$

Q. Probability of four son to a couple is:

1. $\frac{1}{4}$
2. $\frac{1}{8}$
3. $\frac{1}{16}$
4. $\frac{1}{32}$

Q. In our society, women are blamed for producing female children. Choose the correct option for sex determination in humans.

1. Due to some defect like aspermia in man
2. Due to genetic makeup of some particular sperm which fertilizes the egg
3. Due to genetic makeup of the eggs
4. Due to some defect in women

Q. A family has five girls and no son, the probability of the occurance of son in 6${}^{th}$ child is

1. 1/2
2. 1/5
3. 1
4. 1/4

Q. Sex determination by chromosomes in human and Drosophila is through.

1. XX-XO
2. ZZ-ZW
3. XX-XY
4. Both A and B

Q. Sex determination in human being is ________

1. XX-XX Type
2. XX-XO type
3. XX-XY types
4. XO-XX

Q. (a) If a sperm with 'X' chromosome fertilizes with an ovum with 'X' chromosome, what will be the gender of the baby?
(b) Who determines the sex/gender of the baby, mother or father?
(c) Is it correct to blame the mother for giving birth to a baby girl?
(d) Are all our characters resembles our parents?