Chapter 2: Mendelian Inheritance

Question 1

Why did Mendel chose to study pea plants?

Answer 1

Their ability to carry out self-fertlization or cross fertlization

Several varieties which a character existed in two distinct variants

Question 2

A Punnett square is used to predict the outcome of a __-__ cross and __-__ experiment

Answer 2

single-factor; self-fertilization

Question 3

What were the three key ideas Mendel proposed regarding inheritance?

Answer 3

Traits may be dominant or recessive
Genes are passed unaltered from generation to generation
Law of segregation

Question 4

Describe the Law of Segregation.

Answer 4

two copies of a gene segregate (or separate) from each other during transmission from parent to offspring

Question 5

Describe the Law of Independent Assortment

Answer 5

Two different genes will randomly assort their alleles during the formation of haploid cells

Question 6

A Punnett square can also be used to predict the outcomes of a __ factor cross

Answer 6

two

Question 7

Which method should you use for solving the outcomes of crosses involving three or more genes?

Answer 7

forked-line methods

Question 8

Describe the product rule.

Answer 8

finds the probability that two or more independent outcomes will occur is equal to the product of their individual probabilities

Question 9

The binomial expansion equation is used to predict the probability of?

Answer 9

a given set of two unordered outcomes

Question 10

What is the chi square test used for?

Answer 10

To determine the validity of a hypothesis

Question 11

What are the two most prominent theories of inheritance that have been proposed?

Answer 11

Theory of Pangenesis
Theory of Preformationism

Question 12

What is the Theory of Pangenesis?

Answer 12

genetic information (gemmules) travel from different parts of the body to the reproductive organs where it is transferred to gametes

Question 13

What is the Theory of Preformationism?

Answer 13

homonuculus

Question 14

Blending theory states that?

Answer 14

hereditary traits can blend together generation after generation

Question 15

Mendel chose to study _ different traits

Answer 15

seven

Question 16

What is the difference between cross-fertilization and self-fertilization?

Answer 16

cross: pollen and egg from different plants
Self: pollen and egg from same plant

Question 17

Mendel found a : ration when performing a monohybrid cross.

Answer 17

3:1

Question 18

Mendel’s data suggested which theory?

Answer 18

Particulate theory of inheritance

Question 19

What did Mendel postulate after the 3:1 ratio monohybrid cross?

Answer 19

two discrete hereditary factors (alleles) from each parent
may be homo or hetero
can be dom or recessive
law of segregation
randomized process

Question 20

Define a genotype

Answer 20

specific allelic composition of an individual (i.e. TT; Tt; tt)

Question 21

Define a phenotype

Answer 21

the physical appearance of an individual
(i.e tall or short)

Question 22

The phenotype is a product of the __ and the __

Answer 22

genotype; environment

Question 23

How did Mendel verify his principle of segregation?

Answer 23

Test cross

Question 24

Describe a test cross

Answer 24

an organism w a known phenotype but unknown genotype is crossed w an organism that has the recessive phenotype (homo recess)

Question 25

What is the predicted phenotypic ratio of independent assortment?

Answer 25

9:3:3:1

Question 26

Define a loss-of-function allele

Answer 26

an allele that encodes an RNA or protien that is nonfunctional or compromised in function

Question 27

What is the benefit of loss-of-function alleles?

Answer 27

Modern genetic testing/ understanding

Question 28

What is the one caveat to using the forked line method?

Answer 28

genes must not be linked

Question 29

If n=# of heteroxygous gene pairs involved

Number of possible gametes =

Number of different genotypes in zygotes=

Number of different phenotypes in zygotes=

Proportion of homozygous recessive in F2=

Answer 29

2^n

3^n

2^n

(1/4)^n

Question 30

The product rule deals with __ events

Answer 30

independent

Question 31

The sum rule deals with __ events

Answer 31

mutually-exclusie

Question 32

How can I use the sum rule if two events are not mutually exclusive?

Answer 32

P(A or B) = P(A) + P(B) - [P(A) x P(B)]

Question 33

The 3:1 and 9:3:3:1 rations are based on what four assumptions?

Answer 33

Dominance/ recessiveness of alleles
Complete segregation
Independent assortment
Random fertilization

Question 34

What is the chi-square test used for?

Answer 34

determines ‘goodness of fit’

Question 35

A low chi square value indicates a __ probability that the observed deviations could be due to random chance alone

Answer 35

high

Question 36

A high chi square value indicates a __ probability that the observed deviations are due to random chance alone

Answer 36

high