A man who is an achondroplastic dwarf with normal vision marries a color-blind woman of normal height. The man's father was six feet tall, and both the woman's parents were of average height. Achondroplastic dwarfism is autosomal dominant, and red-green color blindness is X- linked recessive. What proportion of their sons would be color-blind and of normal height?

Male pattern baldness is a ___________ trait.

Which of a women's grandparents could not be the source of any of the genes on either of her X-chromosomes?