WAEC Biology Past Questions & Answers - Page 120

596.

Which of the following traits in humans can be affected by environmental factors?

A.

skin colour

B.

eye colour

C.

baldness

D.

tongue-rolling

Correct answer is A

No explanation has been provided for this answer.

597.

What will be the genotypic ratio when two heterozygous red pea plants are crossed?

A.

1 : 0

B.

1 : 2 : 1

C.

2 : 1

D.

3 : 1

Correct answer is B

No explanation has been provided for this answer.

598.

In man, sex is determined by the inheritance of

A.

 a pair of homologous chromosomes

B.

an extra chromosome in the cells of a female

C.

a dominant gene for maleness present in man

D.

two similar X chromosomes in the female and X and Y chromosomes in the male

Correct answer is D

No explanation has been provided for this answer.

599.

The ability of some individuals to taste phenylthiocarbamide (PTC) is a

A.

morphological adaptation

B.

morphological variation

C.

physiological adaptation

D.

physiological variation

Correct answer is D

No explanation has been provided for this answer.

600.

Which of these physiological variations is sex-linked? 

A.

albinism

B.

blood groups

C.

sickle-cell anaemia

D.

haemophilic condition

Correct answer is D

No explanation has been provided for this answer.