CUET UG Genetics and Evolution MCQ Practice

Haemophilia is correctly described as X-linked recessive disorder affecting blood clotting.

Aneuploidy is a chromosomal abnormality in which an individual has one or more extra or missing chromosomes due to nondisjunction during meiosis.

Among the given disorders:
(A) Haemophilia
A sex-linked recessive genetic disorder caused by mutation in genes responsible for blood clotting factors.
It is a single-gene disorder, not due to aneuploidy.
(B) Down's Syndrome
Caused by Trisomy 21 (an extra copy of chromosome 21).
It is a classic example of aneuploidy.
(C) Thalassemia
An autosomal recessive single-gene disorder affecting haemoglobin synthesis.
It is not caused by a change in chromosome number.
(D) Turner's Syndrome
Caused by monosomy X (45, X).
Individuals have only one X chromosome instead of two.
It is an example of aneuploidy.

Gene flow is correctly described as transfer of alleles between populations through migration and reproduction.

Colour blindness is commonly X-linked recessive defect in color vision.