Download Dominant-Recessive Genes Principle

PSY201 – General Psychology
Handout #3
DOMINANT-RECESSIVE GENES PRINCIPLE
Use the Dominant-Recessive Genes Principle to answer the following questions:
1.
A man who has red hair (recessive) marries a woman who has black hair
(dominant) whose mother had red hair. What are the chances that their first
child will have red hair?
2.
A woman who has strait hair (recessive) marries a man who has curly hair
(dominant). There is no one in his family that has strait hair. What are the
chances that their first child will have strait hair? What are the chances that
their second child will have curly hair? What are the chances that any of their
children will carry the gene for strait hair?
3.
A man and a woman both have facial dimples (dominant), but their first child
does not have dimples. What are the chances that their second child will not
have dimples?
4.
A man and a woman both have normal vision (dominant). Their first child
has normal vision also, but their second child has nearsightedness (recessive).
What are the chances that their 3rd child will have normal vision? What are
the chances their 3rd child will carry the gene for nearsightedness?