Question

Which of the following has normal sex chromosomes?
(A) Down syndrome
(B) Klienfelter syndrome
(C) Turner syndrome
(D) Super female

Answer 1

Hint: When faulty cell division results in extra genetic material from chromosome 21 being produced, Down's syndrome is a genetic condition. Intellectual disabilities, developmental delays, and a distinctive facial appearance are all effects of down's syndrome. It might be linked to thyroid or cardiac conditions.

Complete Step by Step Answer:
Aneuploidy, a condition where the number of chromosomes in a cell or organism deviates from multiples of the haploid genome, is caused by errors in chromosome segregation. Chromosome mis-segregation during meiosis, which results in aneuploidy, is a key contributor to infertility and inherited birth abnormalities.

Down’s syndrome is due to failure of segregation of chromosome number 21 which is not a sex chromosome. Down syndrome can be caused by trisomy 21 (nondisjunction), translocation, or mosaicism. 95% of known cases of Down syndrome are caused by trisomy 21 (nondisjunction).

Klinefelter syndrome is due to additional copy of X chromosome, it majorly affects males that is it has XXY karyotype, this is due to failure of segregation in X chromosome which is a sex chromosome.
A missing or partially deleted X chromosome causes Turner syndrome, a condition that mostly affects females. Turner syndrome can result in a wide range of medical and developmental problems, such as short stature, ovarian failure, and heart defects.

A genetic abnormality that results in some girls having an additional X chromosome. Usually, a defective egg or sperm cell or a mistake made early in the embryo's development causes triple X syndrome. Many women have little, if any, symptoms. The majority of the time, therapy is not required.

So, option (A) is correct.

Note: Aneuploidy is when a cell has an abnormally high number of chromosomes. In this instance, there is one additional chromosome. A cell is said to be polyploid if it has an extra set of chromosomes. A completely new set of chromosomes is present.