Unit 5: Chapter 14

Question 1

hybridization

Answer 1

mating two different true-breeding varieties

Question 2

P generation

Answer 2

true breeding parents

Question 3

F1 generation

Answer 3

hybrid offspring of the P generation

Question 4

F2 generation

Answer 4

the offspring of F1 when they self pollinate

Question 5

first concept

Answer 5

there are alternate alleles for each trait and each gene resides at a specific locus on a specific chromosome

ex: purple versus white, long vs short

Question 6

second concept

Answer 6

one allele from each parent is inherited

the two alleles at a locus could be identical or different

Question 7

third concept

Answer 7

domination

the dominant allele determines the organism’s phenotype

Question 8

fourth concept

Answer 8

law of segregation

the two alleles available separate during gamete formation and end up in different gametes during anaphase 1

therefore an egg or sperm gets only one allele

Question 9

testcross

Answer 9

breed a mystery individual with a homozygous recessive individual

if offspring display recessive phenotype, the mystery one must have been heterozygous

Question 10

the law of independent assortment

Answer 10

each pair of alleles segregated independently of other pairs during gamete formation

genes located near each other tend to be inherited together

Question 11

probability rule for 2 independent events occurring together

Answer 11

multiply

Question 12

probability that events can occur in two different ways

Answer 12

add together the two separate always after multiplying

Question 13

codominance

Answer 13

two alleles affect the phenotype in separate equal ways

a flower with red and white petals

Question 14

incomplete dominance

Answer 14

the traits get mixed

a flower with pink petals

Question 15

pleiotropy

Answer 15

genes have multiple phenotypic effects

multiple symptoms of a disease

Question 16

polygenic inheritance

Answer 16

when multiple genes affect one trait

like skin color

Question 17

true breeding plants

Answer 17

plants that produce offspring of the same variety when they self-pollinate

Question 18

epistasis

Answer 18

a gene at one locus affects a gene at another

mouse has genes for coat color and the presence of hair at all. if they don’t get the dominant allele for hair, then they can’t receive a coat color.