Question

a couple has a child with down syndrome. which of the following is the most probable cause of the child's condition? a) the man's family has a predisposition for down syndrome. b) the woman's genome has a chromosomal duplication. c) one member of the couple underwent nondisjunction in somatic cell production. d) one member of the couple underwent nondisjunction during meiosis.

Answer 1

The most probable cause of Down syndrome is if one member of the couple undergoes nondisjunction during meiosis, resulting in an extra copy of chromosome 21.

Step-by-step explanation:

The most probable cause of the child's condition of Down syndrome is option d) one member of the couple underwent nondisjunction during meiosis. Down syndrome is caused by having three copies of chromosome 21, a condition known as trisomy 21. The most common cause of trisomy 21 is chromosomal nondisjunction during meiosis, which means that the chromosomes fail to separate correctly, resulting in an extra copy of chromosome 21.