A recessive gene that is on a human X chromosome?

Question

A. is more likely to be expressed in females.

B. will be expressed equally by males and females.

C. is more likely be expressed if it is heterozygous.

D. will never be expressed in females.

E. is more likely to be expressed by males.

Answer 1

E -  males have only one X-chromosome so even if the gene is recessive, it will be expressed in males. Females need both X's to have a recessive gene for it to be expressed and it is more unlikely to happen.

Answer 2

E.

The homologous chromosome to X chromosome in men is the Y chromosome. Normally homologous chromosomes have the same genes at the same location. both may be dominant or recessive or one dominant and one recessive.

The Y chromosome though homologous to the X chromosome is entirely different and has different genes as compared to the X chromosome. thus even if a recessive trait is passed on to a male through the X chromosome, it will be expressed as there is no corresponding dominant gene/allele on the Y chromosome.