Genetics

Question 1

Father of Genetics

Answer 1

Gregor Mendel

• Austrian monk
• experimented with peas

Question 2

Why Peas?

Answer 2

• many offspring
• easy to grow
• short generation time
• many varieties
• each plant is hermaphrodidic

Question 3

Law of Segregation

Answer 3

• each parent has 2 units that it could possibly pass on for each trait
• two units split up as pollen and eggs

Question 4

Nondisjunction

Answer 4

failure of separation of chromosomes during meiosis

Question 5

Law of Independent Assortment

Answer 5

each trait is inherited independently from every other trait

*just because a pea is green does not mean it will be round

Question 6

Gene

Answer 6

segment of DNA that codes for a specific protein trait

Question 7

Allele

Answer 7

• component of a gene

- organisms typically have 2 for each

Question 8

Dominant Allele

Answer 8

• can overshadow another

- designated with CAPITAL letter

Question 9

Recessive Allele

Answer 9

• can be overshadowed

- designated with LOWER CASE letter

Question 10

Homozygous

Answer 10

• having some form of allele for a gene
• BB = homozygous dominant
• bb = homozygous recessive

Question 11

Heterozygous

Answer 11

• having the opposite form of alleles for a gene

- Bb

Question 12

Genotype

Answer 12

• specific combination of alleles for a gene

- BB, bb, Bb

Question 13

Phenotype

Answer 13

• the physical expression of a genotype

- skin color, eye color, hair color

Question 14

Hybrid

Answer 14

an individual who is the result of crossing two sexually reproducing parents

Question 15

Generation Vocabulary

Answer 15

P= parent
F1= first filial
F2- second filial

Question 16

Punnett Squares

Answer 16

visual representation for the probability of allele inheritance in offspring

Question 17

Monohybrid Cross

Answer 17

tracing the inheritance of one gene

*4 squares

Question 18

Monohybrid Cross Ratios

Answer 18

geno 1:2:1

pheno 3:1

Question 19

Dihybrid Cross Ratio

Answer 19

9:3:3:1

Question 20

Dihybrid Cross

Answer 20

• 16 possible genotypes

- 4 possible phenotypes

Question 21

Incomplete Dominance

Answer 21

• two different alleles combine to create an intermediate phenotype of a given trait
• red flowers + white flowers = pink flowers

Question 22

Codominant Traits

Answer 22

• traits occur when both alleles are expressed in one heterozygous individual
• human blood type

Question 23

Polygenic Traits

Answer 23

• interactions of many genes are responsible for a single trait
• skin color

Question 24

Epistasis

Answer 24

• interaction of one gene with another will alter the phenotype outcome
• albanism

Question 25

Pleiotropy

Answer 25

• one gene influences many different characteristics

* sickle cell anemia

Question 26

Vestigial

Answer 26

“remnants”

*appendix