Basics of Inheritance

Question 1

Homozygote

Answer 1

An individual organism possessing two of the same alleles at a locus

Question 2

Addition rule of probability

Answer 2

the probability of a single, mutually exclusive event can be determined by adding the probabilities of the two or more different ways in which this single event could take place

allows for predicting the likelihood of a single event that can happen in two or more ways

Question 3

Genotype

Answer 3

set of alleles possessed by an individual organism

Question 4

Principle of Segregation (Mendel’s First Law)

Answer 4

each individual diploid organism has a pair of alleles (a copy) for a particular trait, copies of genes separate/segregate so that each gamete receives only one allele; used when thinking about one trait

Question 5

Segregation results from

Answer 5

the separation of homologous chromosomes in meiosis

Question 6

Independent assortment results from

Answer 6

the independent separation of chromosomes in anaphase 1 of meiosis

Question 7

Multiplication rule of probability

Answer 7

the probability of two independent events occurring together is the product of their probabilities of occurring independently; allows for predicting the probability of two or more independent events occurring together

Question 8

P

Answer 8

Parental generation

Question 9

F1

Answer 9

first filial generation

Question 10

F2

Answer 10

second filial generation

Question 11

Gene

Answer 11

basic unit of heredity; an inherited factor (encoded in the DNA) that helps determine a characteristic

Question 12

Allele

Answer 12

one of two or more alternative forms of a gene

Question 13

Locus

Answer 13

specific place on a chromosome occupied by an allele

Question 14

Heterozygote

Answer 14

an individual organism possessing two different alleles at a locus

Question 15

Phenotype/Trait

Answer 15

the appearance or manifestation of a characteristic

Question 16

Characteristic/Character

Answer 16

an attribute or feature possessed by an organism

Question 17

Principle of Independent Assortment (Mendel’s Second Law)

Answer 17

the alleles of two (or more) different genes get sorted into gametes independently of one another; the allele a gamete receives for one gene does not influence the allele received for another gene; used when thinking about two or more different traits
ex: seed shape will sort independently of seed color

Question 18

True Breeding

Answer 18

all offspring resulting from parental crosses will have the same phenotype; no matter how many times a cross is performed, identical phenotypes will occur each time; refers to organisms that are homozygous for genes (both alleles are the same, so PP instead of Pp)

Question 19

Punnett Square

Answer 19

a square diagram that is used to predict the genotypes (unique DNA patterns) of a particular cross or breeding experiment; phenotypes (physical expression of genotypes) can also be predicted

Question 20

Probability

Answer 20

A number that describes how likely it is that an event will occur; 1 = event is certain to happen, 0 = event cannot possibly happen, and all other events have a probability between 0 and 1

Question 21

How many potential outcomes are there for two genes?

Answer 21

16