BIOLOGY
JAMB 2011 - Question 42
Biology 2011 JAMB Past Questions - Question 42: The inheritable characters that are determined by a gene located only on the X-chromosome is
Choose the most appropriate option for the gap .
A:
B:
C:
D:
Correct Answer
D
Explanation
The characters attached to the genes attached only on the X chromosome are sex-linked characters. Such characters are baldness, colour blindness and haemophilia. Homozygous is a condition in which the two genes responsible for the transmission of a character are similar eg TT. fortallnessortt for shortness. • Dominant character is the character that expresses itself in the appearance of an organism even in the presence of recessive character. Recessive character is the character that expresses itself only in a homozygous state (tt) but remains hidden or marked once the dominant character is present.

