Chapter 10 Patterns of Inheritance

Question 1

Genes encode __.

Answer 1

proteins

Question 2

What creates new alleles?

Answer 2

mutations

Question 3

What is a chromosome?

Answer 3

continuous molecule of DNA with associated proteins

Question 4

What are the chromosome pairs a diploid contains?

Answer 4

22 homologous autosomes and one set of sex chromosomes (23 pairs in total = 46)

Question 5

What does fertilization do?

Answer 5

unites gametes and restores the diploid number (46)

Question 6

What did Mendel’s experiments do?

Answer 6

uncovered basic laws of inheritance

Question 7

Why did Mendel study inheritance through pea plants?

Answer 7

developed quickly, produce abundant offspring, and easy to breed

Question 8

What happens in true-breeding?

Answer 8

Self-fertilization yields only offspring identical to the parent

Question 9

What happens in a hybrid?

Answer 9

Characteristics from 2 different parents

Question 10

The dominant allele is…

Answer 10

always expressed if present

Question 11

The recessive allele is…

Answer 11

masked by dominant allele

Question 12

In a gene, a cell’s two alleles may be?

Answer 12

alike or different

Question 13

Heterozygous:

Answer 13

different, phenotype = dominant gene (Bb)

Question 14

Homozygous:

Answer 14

same, dominant (BB), recessive (bb)

Question 15

What is a phenotype?

Answer 15

a physically observed characteristic

Question 16

What is a wildtype?

Answer 16

allele that is most common in a population

Question 17

A change in a gene is a…

Answer 17

mutation

Question 18

Mutations can create…

Answer 18

mutant phenotypes

Question 19

What does P stand for?

Answer 19

Purebred Parental generation

Question 20

What does F1 stand for?

Answer 20

1st generation of offspring

Question 21

What does F2 stand for?

Answer 21

2nd generation of offspring

Question 22

Two alleles of a gene end up in…

Answer 22

different gametes

Question 23

How many genes does a Simple Punnett Square track?

Answer 23

one

Question 24

What is monohybrid crossing?

Answer 24

mating between 2 individuals that are heterozygous for the same gene (Bb, Bb)

Question 25

What does a testcross reveal?

Answer 25

an unknown genotype by breeding the individual to a homozygous recessive individual

Question 26

What is Mendel's Law of Segregation?

Answer 26

Two alleles of the same gene separate into different gametes

Question 27

How are genes on different chromosomes inherited?

Answer 27

independently

Question 28

Tracking 2-gene inheritance requires what?

Answer 28

a larger Punnett Square

Question 29

What is dihybrid crossing?

Answer 29

mating between individuals that are heterozygous for two genes

Question 30

What does Mendel's Law of Independent Assortment and Meiosis state?

Answer 30

Inheritance of 1 gene does not affect the inheritance of another gene on a different chromosome. Independent Assortment occurs because homologous pairs of chromosomes align randomly during Metaphase I of Meiosis.

Question 31

What aids the completion of complex Punnett Squares?

Answer 31

The Product Rule (Rule is an alternative to Punnett squares for following the inheritance of 2 or more traits at a time)

Question 32

Genes on the same chromosome may be what?

Answer 32

inherited together

Question 33

What are linked genes?

Answer 33

genes located on the same chromosome

Question 34

What are linkage genes?

Answer 34

Collections of genes that are often inherited together

Question 35

What is crossing over?

Answer 35

Farther apart two linked genes are on a chromosome

Question 36

What have studies of linked genes yielded?

Answer 36

chromosomes maps

Question 37

What have breeding studies revealed?

Answer 37

the crossover frequencies used to create linkage maps

Question 38

What is incomplete dominance?

Answer 38

Alleles are heterozygous in incomplete dominance, originally from two homozygous

Question 39

What is codominance?

Answer 39

Alleles are heterozygous but contain two dominant alleles, both phenotypes are displayed

Question 40

Gene expression can alter what?

Answer 40

phenotypic rations

Question 41

What happens when a gene is Pleiotropic?

Answer 41

gene affects multiple phenotypes (When multiple proteins participate in a biochemical pathway, mutations in genes encoding any of the proteins can produce the same phenotype)

Question 42

What happens in Epitasis?

Answer 42

one gene masks the affect of another

Question 43

Sex genes for a female:

Answer 43

XX

Question 44

Sex genes for a male:

Answer 44

XY

Question 45

What disorders affect males more than females?

Answer 45

X-linked recessive disorders

Question 46

X-linked recessive disorders?

Answer 46

- Hemophilia A - Red-green color blindness - Duchenne Muscular Dystrophy

Question 47

X-linked dominant disorders?

Answer 47

- extra hairiness | - retinis pigmentosa

Question 48

What does X-inactivation prevent?

Answer 48

"double dosing" of proteins

Question 49

What does X-inactivation shut down?

Answer 49

all but one X-chromosome in a female mammal

Question 50

What is the purpose of a pedigree model?

Answer 50

traces phenotypes in families and reveals modes of inheritance

Question 51

What is an Autosomal Dominant disorder?

Answer 51

disorder from one affected parental

Question 52

Autosomal Dominant disorders?

Answer 52

- Huntington Disease - Marfan Syndrome - Polydactyl

Question 53

What is an Autosomal Recessive disorder?

Answer 53

disorder from two affected parents (affects mostly males)

Question 54

Autosomal Dominant disorders?

Answer 54

- Cystic Fibrosis - Albinism - Tay-Sachs disease