Chapter 2.2: Genetic Analysis According to Mendel

Question 1

How does a specific gene affect phenotype?

Answer 1

o A specific gene determines a specific enzyme whose activity may affect the phenotype in any number of ways depending on the biochemical pathway

Question 2

What does Mendel’s Law of Segregation state?

Answer 2

 Mendel’s Law of Segregation: the two alleles for each trait separate (segregate) during gamete formation, and then unite at random, one from each parent at fertilization

Question 3

What do monohybrid crosses reveal?

Answer 3

• Monohybrid Crosses Reveal Units of Inheritance and the Law of Segregation

Question 4

What is an observable characteristic?

Answer 4

phenotype

Question 5

What is an individual with a homozygous genotype?

Answer 5

homozygote

Question 6

Define phenotype

Answer 6

an observable characteristic

Question 7

What is a mating in which an individual showing the dominant phenotype is crossed with an individual expressing the recessive phenotype?

Answer 7

testcross

Question 8

What is a dihybrid?

Answer 8

o A dihybrid individual is one that is heterozygous for 2 genes at the same time

Question 9

How do alleles relate to encoding proteins?

Answer 9

o The dominant allele determines a normally functioning protein, while the recessive allele does not encode a functional protein

Question 10

Define heterozygote

Answer 10

an individual with a heterozygous genotype

Question 11

Define genotype

Answer 11

alleles present in an individual

Question 12

What was the first filial (F1) generation in Mendel’s experiment?

Answer 12

 When crossed peas were all yellow; first filial (F1) generation

Question 13

What is an individual with a heterozygous genotype?

Answer 13

heterozygote

Question 14

What is a monohybrid cross?

Answer 14

cross between single trait hybrids

Question 15

Define gametes

Answer 15

the specialized cells—eggs within the ovules of the female parent and sperm cells within the pollen grains—that carry genes between generations

Question 16

What are recombinant types?

Answer 16

o New phenotypic combinations in offspring are called recombinant types

Question 17

What are individuals having two different alleles for a single trait?

Answer 17

monohybrids

Question 18

Define alleles

Answer 18

alternative forms of a single gene

Question 19

What is a branched-line diagram?

Answer 19

 A branched-line diagram shows all the possibilities for a gene in a sequence of columns

Question 20

What are the alleles present in an individual?

Answer 20

genotype

Question 21

Define monohybrids

Answer 21

individuals having two different alleles for a single trait

Question 22

Define punnett square

Answer 22

a simple and convenient method for tracking the kinds of gametes produced as well as all the possible combinations that might occur at fertilization

Question 23

Define homozygous

Answer 23

two of the same alleles for a trait

Question 24

What are alternative forms of a single gene?

Answer 24

alleles

Question 25

What reveals units of inheritance and the law of segregation?

Answer 25

monohybrid crosses

Question 26

What are the specialized cells—eggs within the ovules of the female parent and sperm cells within the pollen grains—that carry genes between generations?

Answer 26

gametes

Question 27

What is the product rule?

Answer 27

o The product rule states that the probability of 2 or more independent events occurring together is the product of the probabilities that each event will occur by itself

Question 28

What is the sum rule?

Answer 28

o The sum rule states that the probability of either of 2 such mutually exclusive events occurring is the sum of their individual probabilities

Question 29

What was the parental (P) generation in Mendel’s experiment?

Answer 29

o Mendel planted pure-breeding green and pure-breeding yellow peas and allowed them to grow into the parental (P) generation

Question 30

What are matings between the F1 progeny of pure-breeding parents that differed in 3 or more unrelated traits?

Answer 30

multihybrid cross

Question 31

Define homozygote

Answer 31

an individual with a homozygous genotype

Question 32

What is a cross between single trait hybrids?

Answer 32

monohybrid cross

Question 33

Define testcross

Answer 33

a mating in which an individual showing the dominant phenotype is crossed with an individual expressing the recessive phenotype

Question 34

What are two different alleles for a trait?

Answer 34

heterozygous

Question 35

What was the second filial (F2) generation in Mendel’s experiment?

Answer 35

 Resulted in 3:1 ratio of yellow to green; second filial (F2) generation

Question 36

Define heterozygous

Answer 36

two different alleles for a trait

Question 37

What are two of the same alleles for a trait?

Answer 37

homozygous

Question 38

What does the Law of Independent Assortment state?

Answer 38

 Law of Independent Assortment: During gamete formation, different pairs of alleles segregate independently of each other

Question 39

Define multihybrid cross

Answer 39

matings between the F1 progeny of pure-breeding parents that differed in 3 or more unrelated traits

Question 40

What is a simple and convenient method for tracking the kinds of gametes produced as well as all the possible combinations that might occur at fertilization?

Answer 40

punnett square