pedigrees

Question 1

what is a pedigree?

Answer 1

a family tree that shows how a trait is inherited

Question 2

What shape is the male symbol in a pedigree?

Answer 2

a square

Question 3

What shape is the female symbol in a pedigree?

Answer 3

a circle

Question 4

How do you know if the trait is present or not?

Answer 4

Shaded shape= presence of trait.
Unshaded shape= absence of trait

Question 5

How do you tell if two individuals are mating partners?

Answer 5

There will be a line connecting the two individuals

Question 6

What are the four types of inheritance ?

Answer 6

• autosomal recessive
• autosomal dominant
• X linked recessive
• X linked dominant

Question 7

What are some characteristics of Autosomal recessive inheritance?

Answer 7

• trait is rare in pedigree
• trait skips generations
• males + females are equally affected

Question 8

What are some characteristics of Autosomal dominant inheritance?

Answer 8

• trait is common in pedigree
• dosen’t skip generation
• affected individuals transmit trait to half of children

Question 9

What are some characteristics of X linked recessive inheritance?

Answer 9

• rare in pedigree
• skips generations
• affected father dosen’t pass on to their sons, because it’s carried on x chromosomes

Question 10

What are some characteristics of X linked dominant inheritance?

Answer 10

• common in pedigree
• affected fathers pass to all daughters but not son
• dosen’t skip generations

Question 11

How do you know if the trait is autosomal?

Answer 11

• larger number of males than females who are affected.

Question 12

How do you know if the trait is X linked?

Answer 12

• if there is a 50/50 ratio between males and females who are affected.