Lesson 8 Terms

Question 1

Alleles

Answer 1

different versions of the same genes

Question 2

Carrier

Answer 2

an individual who doesn’t exhibit a trait but carries the gene for the trait — the trait is in the genotype but not the phenotype for that individual

Question 3

Codominance

Answer 3

occurs when two alleles for a gene are both expressed but the characteristics are seen side by side

Question 4

Cross-pollinate

Answer 4

the male gamete of one plant fertilizes the female gamete of another plant

Question 5

Dihybrid cross

Answer 5

the type of cross that deals with 2 different pairs of traits at the same time

Question 6

Genotype

Answer 6

the combination of alleles carried by an organism, all genes collectively, whether dominant or recessive

Question 7

Gregor Mendel

Answer 7

the father of modern genetics

Question 8

Heredity

Answer 8

passing on physical or mental characteristics genetically from one generation to the next

Question 9

Heterozygous

Answer 9

when an organism has two different copies of an allele — one dominant and one recessive

Question 10

Homozygous

Answer 10

when an organism has two copies of the SAME allele — either both dominant or both recessive

Question 11

Incomplete dominance

Answer 11

occurs when two alleles are both expressed resulting in a blended phenotype

Question 12

law of independent assortment

Answer 12

alleles of two (or more) different genes are sorted into gametes independently of one another

Question 13

law of segregation (The Riot and the Dance)

Answer 13

the segregation of the alleles (dominant and recessive) into the gametes of an organism is random

Question 14

monohybrid

Answer 14

crosses that only look at one trait of an organism

Question 15

Phenotype

Answer 15

what the organism actually looks like

Question 16

Polygenic inheritance

Answer 16

when a single trait is controlled by multiple sets of genes

Question 17

Purebred

Answer 17

a plant which has only been self-pollinated

Question 18

Recessive

Answer 18

a genetic trait that is not as likely to be passed on to the next generation as the dominant

Question 19

Self-pollination

Answer 19

when a plant has both gametes and fertilizes itself

Question 20

Sex-linked trait

Answer 20

a trait that is determined by a gene found on one of the sex chromosomes

Question 21

Test cross

Answer 21

the process of observing the offspring of a plant to determine if the parent plant is homozygous or heterozygous

Question 22

Thomas Hunt Morgan

Answer 22

an embryologist who studied genetics using fruit flies and as a result discovered sex-linked traits

Question 23

Traits

Answer 23

Characteristics that are inherited

Question 24

x-linked traits

Answer 24

traits coded for only on the X chromosome

Question 25

Dominant

Answer 25

a genetic trait that has a higher likelihood of being passed on to the next generation
(not the fifth of a scale)