Which one of the following pairs of characters is a symptom of a pers…

The correct answer is Option (4) → Females are sterile as their ovaries are rudimentary

Turner’s syndrome comes from the loss of one X chromosome in a human female, so the person has 45 chromosomes (XO). The female is sterile because her ovaries are rudimentary. She is short, and she lacks the secondary sexual characters.

The first three options all describe a different chromosomal disorder, Down’s syndrome. It is caused by an extra copy of chromosome 21 (trisomy of 21).

(1) Short stature with a small round head — Incorrect. This is Down’s syndrome.

(2) Furrowed tongue and partially open mouth — Incorrect. This is also Down’s syndrome.

(3) Palm is broad with characteristic palm crease — Incorrect. This is also Down’s syndrome.

(4) Females are sterile as their ovaries are rudimentary — Correct. This is the feature of Turner’s syndrome.

NCERT Extract:
Chromosomal Disorders – “… Turner’s Syndrome : Such a disorder is caused due to the absence of one of the X chromosomes, i.e., 45 with X0, Such females are sterile as ovaries are rudimentary besides other features including lack of other secondary sexual characters (Figure 4.17 b).”

Figure 4.17 Diagrammatic representation of genetic disorders due to sex chromosome composition in humans : (a) Klinefelter Syndrome; (b) Turner’s Syndrome