Unit 3 - Beyond Mendel

Question 1

Incomplete Dominance

Answer 1

looks like blending hypothesis of inheritance

(RR red flower + rr white flower=Rr pink flower)

Question 2

Codominance

Answer 2

occurs when 2 alleles are phenotypically expressed simultaneously, heterozygotes express both phenotypes

(RR white cow + rr brown cow = Rr half white/brown cow)

Question 3

Polygenic Traits

Answer 3

traits determined by 2+ genes, are “complex” meaning influenced by environmental factors like diet

(Ex. hair color, skin color, eye color, height)

Question 4

A normal karyotype consists of _ autosomes and _ sex chromosomes

Answer 4

44, 2

Question 5

X and Y chromosomes act as

Answer 5

a homologous pair during meiosis

Question 6

Sex-linked inheritance patterns can be observed by

Answer 6

different outcomes of reciprocal crosses

Question 7

Reciprocal Cross

Answer 7

one in which you switch the sex of parent affected by phenotype

Question 8

Mutations in X-linked genes result in

Answer 8

predominantly male diseases (called X-linked disease)

Question 9

Duchenne Muscular Dystrophy is

Answer 9

an X-linked disease caused by mutations in the dystrophin gene

Question 10

Pedigrees

Answer 10

document the inheritance of traits in human families

Question 11

Autosome

Answer 11

non-sex chromosome

Question 12

Pedigree of an autosomal dominant allele causing a disease trait signs=

Answer 12

1.Affected individuals equally male/female
2.Usually only 1 affected parent
3.1 parent=half offspring affected

Question 13

Pedigree of an autosomal recessive allele causing a degree trait signs=

Answer 13

1.Trait may skip generations
2.Male/female equally affected
3.Individuals may have unaffected parents
4.Affected individuals often from incest, typically first cousins

Question 14

X-linked recessive traits are observed

Answer 14

virtually exclusively in males and are often passed through unaffected females