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Chromosomal Disorders MCQ - Practice Questions with Answers

Edited By admin | Updated on Sep 18, 2023 18:34 AM | #NEET

Quick Facts

A disease caused by an autosomal primary non-disjunction is :

Down's syndrome

Klinefelter's syndrome

Turner's syndrome

Sickle cell anemia

A human female with Turner's syndrome:

has 45 chromosome with XO.

has one additional X chromosome.

exhibits male characters.

is able to produce children with normal husband.

Chromosomal Disorders

Down’s Syndrome:

It was described by J Langdon Down in 1866.
It occurs due to the additional copy of chromosome number 21 or trisomy of chromosome 21 in humans and also seen in chimpanzees and other related primates.
Symptoms:
- Individuals are short-statured with small, round head and furrowed tongue.
- Partially open mouth, the palm is broad with characteristic palm crease.
- Slow mental development.

Klinefelter’s Syndrome:

It occurs due to the presence of an additional copy of X-chromosome resulting in the karyotype 45 + XXY which results into 47 chromosomes.
Symptoms:
- Individuals have masculine development but feminine characters like the development of breasts, (gynecomastia) etc.
- Poor bread growth and often sterile and feminine pitched voice.

Turner’s Syndrome:

It is a disorder caused due to the absence of one of the X-chromosome, i.e., 45 with XO.
Symptoms:
- Affected females are sterile as ovaries are rudimentary.
- Lack of secondary sexual characters and poor breast development. Short stature, small uterus, puffy fingers and webbed neck.