Question

A woman has an $X$ -linked condition on one of her $X$ chromosomes. This chromosome can be inherited by

• A. Both sons and daughters
• B. Only daughters
• C. Only grandchildren
• D. Only sonB

Answer 1

The Correct Option is A

To solve this question, we need to understand the genetic inheritance of X-linked conditions. An X-linked condition means that a gene causing the condition is located on the X chromosome. Here's a step-by-step explanation:

1. The woman has two X chromosomes, and one carries the X-linked condition. Her genetic makeup can be considered as XX_c, where X_c is the X chromosome with the condition.
2. During reproduction, a woman passes on one of her X chromosomes to her children. Therefore, each child will inherit one X chromosome from the mother.
3. If the child is a son, he will inherit his X chromosome from his mother and his Y chromosome from his father. Hence, the boy's genetic makeup will be XY, where the X comes from the mother.
4. If the child is a daughter, she will inherit one X chromosome from her mother and one from her father. Hence, the daughter's genetic makeup will be XX.
5. Since both sons and daughters inherit their X chromosome from their mother, both can inherit the X-linked condition carried on the mother's X chromosome.

Therefore, the condition can be inherited by both sons and daughters. So, the correct answer is: Both sons and daughters.

Let's rule out the other options:

• Only daughters: This option is incorrect as sons can also inherit the X chromosome from their mother.
• Only grandchildren: This option is irrelevant as the question specifically addresses the direct inheritance by her children, not grandchildren.
• Only sons: This option is incorrect as daughters also inherit one X chromosome from their mother, allowing them to inherit the condition as well.