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Flashcards in Mendel's Genetics Deck (34):
1

Who was Mendel?

Austrian monk
worked with pea plants in 1860

2

Why was Mendel important?

Knew male+female contributed but didn't know how
Described how traits can be passed on from generation to generation

3

What is true breeding?

Modern term= homozygous
Breeding two homozygous individuals together

4

What does P stand for?

Parental generation

5

What does F1 stand for?

first filial generation

6

What does F2 stand for?

second filial generation

7

Why did Mendel use peas in his experiments?

he could control pollination
characteristics were easily identifiable

8

What is the law of segregation?

each individual has 2 factors for each trait
the factors separate (segregate) when gametes are made
each gamete only gets one factor
fertilization gives the new organism two factors for each trait

9

What are traits controlled by alleles?

dominant and recessive

10

What is a locus?

spot on chromosome where genes are located

11

What are the two genotypes?

Heterozygous
Homozygous

12

What is the phenotype?

physical appearance

13

What is a monohybrid cross?

1 trait, two heterozygotes

14

In two trait inheritance, are the dominant and recessive genes inherited together?

No, they don't stick together just because they're both dominant or recessive

15

What are recombinant offspring?

They have different traits than their parents

16

What are parental-offspring?

They have the same traits as their parents

17

What is the relationship between the law of segregation and the law of independent assortment?

Whatever genes the parent has, the traits separate (segregate) and then in anaphase (meiosis), they assort randomly

18

In the law of segregation, each gamete gets __ trait.

1

19

In the law of independent assortment, the gametes get __ possible combos of traits.

All

20

What is incomplete dominance?

The heterozygote is a blended phenotype but not a blended genotype. (Pink flowers, compared to red and white, or straight, wavy, and curly hair)

21

What is an example of multiple-allele traits?

ABO blood group- 3 alleles

22

In the ABO blood group, how many alleles are inherited?

2 of 3

23

Both Ia and Ib are ____ to i.

dominant

24

Ia and Ib are ____, meaning both will be equally expressed in the heterozygote.

codominant

25

What is epistasis?

One gene alters the expression of another gene

26

What is an example of epistasis?

Labrador retrievers and coat color (ee in labs)

27

To determine the probability of two traits occurring together, what must be done?

The probability of the individual traits must be multiplied together

28

To determine individual probabilities, what must be done?

Each individual trait must be punnet squared, and those probabilities can then be multiplied

29

Explain Mendel's experiment

He cross-pollinated 1 true breeding tall plant, and 1 true breeding short plant
Harvested the F1 seeds and planted them so they could self pollinate

30

What is a one-trait testcross?

Used to determine the dominant genotype (PP or Pp)
The recessive is known (pp)

31

What is polygenic inheritance?

A trait is controlled by 2 or more sets of alleles
Each dominant and recessive trait adds up
Results in a lot of variation (bell curve)
Skin color

32

In terms of polygenic inheritance, what are multifactorial traits?

A combination of polygenic and environmental influence
If a person has a certain gene, being in a certain environment can heighten or speed up its expression (HBP disposition, placed in high stress and high sodium intake, develops HBC faster than someone not predisposed to it)

33

What is pleiotropy?

One gene has multiple physical effects

34

The X chromosome is much __ and carries __ genes

larger
more