I believe the first option should be 2, and for the second options, number 2 is right.
An individual who possesses two identical X chromosomes is female.
Since women have a pair of X chromosomes, they are considered homozygous for the X chromosome - the term homozygous refers to having 'two chromosomes of the same type.' In contrast, men typically have different chromosome types - XY.
Hello. This question is not complete. The entire question is: John Allen is being diagnosed for tooth #20. It's Mr. Allen's first visit to the endodontist, and his reported symptoms include pain while chewing on the affected side and a constant dull ache lasting around a week.
How do you think Mr. Allen became aware that he needed to see an endodontist for dental care?
