Principle Of Inheritance And Variation Question 347
Question: Assertion : In humans, most sex-linked genes are present on the X chromosome. Reason : X-chromosome contains a large number of genes with major effects on phenotype.
Options:
A) If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B) If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C) If the assertion is true but the reason is false
D) If both the assertion and reason are false
Show Answer
Answer:
Correct Answer: A
Solution:
Most sex - linked genes in male heterogametic animals are present on the X- chromosome.
Some animals, however, may carry a few genes on the Y chromosome that produce visible effects on the phenotype of the organism.
Y linkage is very rare in higher animal, particularly mammals.
X linkage, on the other hand, is very common in all mammals that have been studied, the mammalian X chromosome contains a larger number of genes with major effects on phenotype.
BETA
