Pedigree

Question 1

Autosomal dominant

Answer 1

• traits appear equally in males and females
• both sex transmit their traits to the offspring
  -DOES NOT SKIP generations
• affected offspring must have an affected parent
• when one parent is heterozygous and the other parent is unaffected, approx. 1/2 of offspring will be affected
• unaffected parents CAN NOT pass the trait

Question 2

autosomal recessive

Answer 2

• usually appear equally in males and females
• skips generations
• affected offspring are born to unaffected parents
• when both parents are heterozygous, 1/4 of the offspring will be affected

Question 3

X-linked recessive

Answer 3

• more males than females are affected
• affected sons are born to unaffected mothers ; thus, the trait skips generation
• mother is heterozygous then 1/2 of her sons are affected
• all daughters of affected fathers are carriers

Question 4

X-linked dominant

Answer 4

• both males and females are affected, usually more females than males
• does not skip generations - affected sons must have an affected father and an affected daughter must have an affected father or mother

Question 5

Y-linked trait

Answer 5

• only males are affected
• passed from father to all sons
• does not skip generations