Question 24 This human karyotype is unusual because chromosome pair a 23 has chromosomes of different shapes. b 21 has an extra chromosome. c 14 has enlarged centromeres. d 10 is missing genetic material.

Answer 1

The description provided suggests that the human karyotype has some abnormalities. Here's a breakdown of each option:

a. 23 has chromosomes of different shapes: This typically indicates a sex chromosome anomaly, possibly such as Turner syndrome (45, X) where there is only one X chromosome or an abnormality involving the presence of multiple sex chromosomes (e.g., Klinefelter syndrome).

b. 21 has an extra chromosome: This refers to Down syndrome (trisomy 21), where there are three copies of chromosome 21 instead of the normal two.

c. 14 has enlarged centromeres: This could indicate structural abnormalities or variants but is not a common observation in typical karyotypes.

d. 10 is missing genetic material: This could indicate deletion syndromes, such as 10p deletion syndrome, where part of chromosome 10 is missing.

Based on the information given, if you're asked which statement represents an unusual feature in the karyotype, option b (the presence of an extra chromosome 21) is the most notable and clinically significant anomaly among humans, as it leads to Down syndrome.

Answer 2

CHOOSE ONE

Answer 3

Based on the descriptions provided, the most unusual feature in a human karyotype is:

b. 21 has an extra chromosome.

This indicates Down syndrome (trisomy 21) and is a well-known genetic abnormality.