Genetics 230: Chapter 3

Front 1

Mendel used _________ ______ as his model system in a experimental approach to study _______________ of _______________.

Back 1

Garden peas. patterns of inheritance

Front 2

Used snow peas because: (6 points)

Back 2

- easy to grow
- true breeding strains
- controlled mating: self-fertilization or cross-fertilization (has both male and female gametes)
- grows to maturity in one season
- has observable characteristics with 2 distinct forms
- can culture offsprings

Front 3

Medel used __ ___________ ___________ each with __ contrasting traits and true breeding strains to keep records on experiments.

Back 3

7 visible feature, 2 contrasting traits

Front 4

Results.....

Back 4

- Unappreciated during his time
- Later rediscovered
- eventually accepted as the basis of Mendelian or transmission, genetics

Front 5

Monohybrid Cross

Back 5

reveals how one trait is transmitted from generation to generation

- Involved a single pair of contrasting traits
- Original P1, parent generation and F1, offspring generation
- Offspring arising from self-fertilization are the F2 generation

Front 6

F1 generation and F2 generation

Back 6

F1: a monohybrid cross, all of the plants have just one of the 2 contrasting traits- Homozygous

F2: 3/4 of the plants exhibit the same trait at F1 generation, and 1/4 exhibit the contrasting trait that disappeared in the F1 generation.

Front 7

Mendel proposed the existence of "particulate ______ ____________" for each trait.

He suggested that these factors ( now called _________) are passed unchanged from generation to generation, determining various traits expressed by each individual plant.

Back 7

unit factors, genes (Depending on which allele is present and expressed)

Front 8

Recriprocal cross

Back 8

Mendel's monohybrid were not sex dependent, the results were the same either way.

Front 9

Mendel proposed 3 postulates of inheritance:

Back 9

- Unit factors exist in pairs
- Pair of unit factors for a single characteristic in an individual- one unit factor (gene) is dominant and other is recessive
- During gamete formation, paired unit factors separate independently

Front 10

_________________ alleles will be expresssed, affecting the phenotype

Back 10

Dominant

Front 11

P1 Generation

Back 11

Parental plants

Front 12

F1 Generation

Back 12

P generation's hybrid offspring

Front 13

F2 Generation

Back 13

A cross of F1 plants

Front 14

Homozygous genotype

Back 14

2 Identical alleles

For each characteristic, an organism inherits 2 alleles. one from each parent.

Front 15

Heterozygous genotype

Back 15

2 different alleles

Front 16

Alleles

Back 16

- alternative versions of genes
- genotype is the listing of alleles an individual carries for a specific gene

Front 17

Genotype

Back 17

Genetic makeup of an individual.

Front 18

Phenotype

Back 18

Physical expression of the genetic make up.

Front 19

Punnett square

Back 19

Allows genotypes and phenotypes resulting from a cross to be visualized easily.

Front 20

Testcross

Back 20

A way to determine whether an individual displaying the dominant phenotype is homozygous or heterozygous for that trait.

Front 21

Dihybrid cross

Back 21

involves 2 pairs of contrasting traits.

Front 22

Product Law

Back 22

Used to predict the frequency with which 2 independent events will occur simultaneously.

Front 23

Mendel's fourth postulate: Independent assortment

Back 23

- traits assort independently during gamete formation
- all possible combinations of gametes will form with equal frequency

Front 24

Punnett square of a dihybrid ratio

Back 24

9:3:3:1

Front 25

Trihybrid cross

Back 25

- demonstrates mendel's principles apply to inheritance of multiple traits
- involving 3 independent traits show that Mendel's rules apply to any number of traits

Front 26

Forked line method

Back 26

- easier to use than punnett square for analysis of inheritance of larger number of traits

Front 27

Chromosomal theory of inheritance

Back 27

Proposed that the separation of chromosomes during meiosis could be the basis for mendel's principles of segregation and independent assortment

Front 28

Major consequence of independent assortment is the production of ____________________ _________________ gametes.

Back 28

genetically, dissimilar

Front 29

________________ ______________ results from independent assortment and is very important to the process of evolution.

Back 29

Genetic variation

Front 30

Sum Law

Back 30

- used to calculate the probability of a generalized outcome that can be accomplished in more that one way

- states that the probability of obtaining any single outcome. where the outcomes can be achieved in 2 for more events, is equal to the sum of the individual probabilities of all such events

Front 31

Conditional probability

Back 31

- when one depends on another, the likelihood of the desired outcome

Front 32

Binomial theorem

Back 32

- used to calculate the probability of any specific set of outcomes among a large number of potential events

Front 33

Chi-Square

Back 33

- denoted by x^2
- evaluates the influence of change on genetic data
- change deviation from an expected outcome is diminished by larger sample size
- used to test how well the data fit the null hypothesis

Front 34

Null hypothesis

Back 34

- assumes there is no real difference between the measured vales (or ratio) and the predicted values (or ratio)

Front 35

Chi-square analysis requires that the ____________ ___ ___________ to be taken into account, since more deviation is expected with higher _______________ ___ ___________.

Back 35

degree if freedom = n-1

n- the number of different categories into which each datum point may fall

Front 36

Once the number of degrees of freedom is determined. the ______ value can be interpreted in terms of a corresponding probability value (p)

Back 36

x^2