3: Basic Principles of Heredity

Question 1

Year Mendel publishes his experiments

Answer 1

1866

Question 2

Birthdate of Modern Genetics, “Rediscovery of Mendel’s work”

Answer 2

1900

Question 3

The Chromosome Theory of Heredity

Answer 3

chromosomes are the carriers of genes

Question 4

states that two alleles of a genes, on maternal and one paternal, separate in equal proportions when gametes are formed (separation of Aa into gametes)

Answer 4

Segregation (Mendel’s First Law)

Question 5

states that alleles at different loci separate independently (Aa separates into gametes regardless of how Bb separates) i.e. genes are not linked

Answer 5

Independent Assortment (Mendel’s Second Law)

Question 6

cross between parents that differ in a single characteristic

Answer 6

monohybrid cross

Question 7

first generation of a cross

Answer 7

P (parental) generation

Question 8

offspring of P generation

Answer 8

F1 (first filial) generation

Question 9

what do monohybrid crosses reveal?

Answer 9

principle of segregation and concept of dominance

Question 10

states that when two different alleles are present in a genotype, only the trait encoded by one of them is observed in the phenotype

Answer 10

concept of dominance

Question 11

F1 x P cross

Answer 11

backcross

Question 12

1st place you can determine which allele is dominant

Answer 12

F1 generation

Question 13

form of progeny testing that reveal the genotype of an individual of dominant phenotype. always cross with a homozygous recessive (A_ x aa)

Answer 13

testcross

Question 14

predicts probability of joint occurrence of independent events (AND)

Answer 14

multiplication rule

Question 15

predicts probability of either occurrence of mutually exclusive events (OR)

Answer 15

addition rule

Question 16

additional information that modifies of conditions the probability for a situation

Answer 16

conditional probability

Question 17

the common allele for a character (usually found in the wild), symbolized with letter and a +

Answer 17

wild type

Question 18

phenotypic ratio of Aa x Aa

Answer 18

3 : 1

Question 19

phenotypic ratio of Aa x aa

Answer 19

1 : 1

Question 20

uniform progeny

Answer 20

all offspring have the same phenotype

Question 21

phenotypic ratio of AA x Aa or two homozygous parents

Answer 21

uniform progeny

Question 22

genotypic ratio of cross between two heterozygotes

Answer 22

1 : 2 : 1

Question 23

genotypic ratio of cross between heterozygote and homozygote

Answer 23

1 : 1

Question 24

genotypic ration of cross between two homozygotes

Answer 24

uniform progeny

Question 25

what do dihybrid crosses reveal?

Answer 25

principle of independent assortment

Question 26

the principle of independent assortment results from...

Answer 26

the principle of segregation in anaphase I

Question 27

heterozygote that possesses a recessive disease allele, but does not express the disease phenotype

Answer 27

carrier