W10 Mendelian Complications

Question 1

Y-linked inheritance:

Answer 1

-Relatively few genes on the Y-chromosome
-Y-linked disorders would only affect males
-All sons of an affected male would have the disorder

Question 2

Mitochondrial inheritance:

Answer 2

-Individuals only inherit mitochondria from their mother
-Can affect both sexes
-Mutations in mitochondrial genes can lead to disease

Question 3

Incomplete dominance:

Answer 3

-Heterozygote is intermediate between the two homozygous forms

Question 4

Co-dominance:

Answer 4

-Where both alleles are active but produce different products

Question 5

Multiple Alleles:

Answer 5

-Some genes can exist as more than two alleles

Question 6

Linkage:

Answer 6

-Some traits and alleles are seen to be inherited together more often than random chance would predict
-Genes on same chromosome more likely to be inherited together
-Don’t segregate independently
-Don’t follow mendelian inheritance patterns
-If two genes on same chromosomes then gametes produced during meiosis are more likely to have parental genotypes
-Crossing over (homologous recombination) can generate recombinant genotypes
-The number of recombinant phenotypes observed indicates how linked two genes are

Question 7

Polygenic inheritance:

Answer 7

-Where a trait is controlled by more than one gene