Genetics Review

Who established modern Genetics?

(aka Father of Genetics)

•Gregor Mendel

What do geneticists call a genetic cross made to

study a single trait?

•Monohybrid Cross

What are distinctive forms of a gene called?

•Alleles

What is any characteristic passed

from parent to offspring?

•A Trait

An organism that receives different alleles

from both parents is a__________

•Hybrid

A punnett square represents the

phenotype of an organism. T or F

•False

How do we represent the allele for a recessive

trait?

•Lowercase letter

How do we represent the allele for a recessive

trait?

•Lowercase letter

A section of a chromosome that codes

for a trait is a

•Gene

What is the likelihood that a particular event

will occur?

•Probability

Which law states that gene pairs separate from

each other during meiosis?

•Law of segregation

If a male organism has the genotype

AABBCCDD and is crossed with a female with aabbccdd, what

would all of their offspring's genotypes

be?•AaBbCcDd

If all the offspring peas in a cross are Rr, then what were the parent’s

genotypes

•RR x rr

What is the genetic makeup of an organism

called?

•Genotype

The branch of Biology that deals with heredity

•Genetics

Write a genotype for a homozygous recessive

trait.

•rr

Passing of traits from parent to offspring

•Heredity

An allele that expresses itself in a hybrid is

a(n)_________.

•Dominant allele

Offspring of the P generation

•F1 generation

What is the genotypic probability of a cross between Bb and Bb?

•1BB:2Bb:1bb•25%BB:50%Bb:25%bb•¼ BB: ½ Bb: ¼ bb

Reasons Mendel studied peas

•Rapid reproduction•Easy to cross pollinate•Distinctive traits•Easy to grow

Offspring of the F1 generation

•F2 generation

Write a genotype for a heterozygous trait.

•Rr

Dominant is to Recessive as Heterozygous is to

•Homozygous

How can we represent Probability?

•Ratio•Fraction•Percentage

A person with brown eyes allele(B) and a blue eye allele (b)has brown eye because of

which law?

•Law of Dominance

Write the genotypes for a cross between two

heterozygous individuals for a single

trait.•Gg X Gg

In Rabbits Black fur (B) is dominant to Brown fur (b)

1 2

3 4

What is this device called?

Punnett Square or Monohybrid cross

What law states that gene pairs segregate

randomly and independently from each

other?

•Law of independent assortment

Which Punnett Square is worked out correctly?

•

D d

DD Dd

DD DdD

D

D d

dd Dd

DD ddD

D

d d

Dd dd

Dd ddD

d

If you flipped a coin five times and it came up on heads, what is

the chance it will come up on heads

next time?

•50%

In Rabbits Black fur (B) is dominant to Brown fur (b)

1 2

3 4

What’s the color of both parents?Black

In Rabbits Black fur (B) is dominant to Brown fur (b)

1 2

3 4

What is the phenotype of Box 2?Black

All of the possible results of a genetic cross

can be shown by using what tool?

•Punnett Square

What is the term for the physical appearance

that an organism expresses?

•Phenotype

In Rabbits Black fur (B) is dominant to Brown fur (b)

1 2

3 4

What is the genotype of box 4?bb

How do the offspring of 2 purebred parents look in

comparison?

•identical

Gregor Mendel used pea plants to show what?

•How traits are inherited

R =Round r =wrinkledY = yellow and y=green

X 6

7 1 3

9 2 5 4

8

What is the genotype of the individual in box 2?RrYy

R =Round r =wrinkledY = yellow and y=green

X 6

7 1 3

9 2 5 4

8

What is the phenotype of the individual in box 1?Round & yellow

R =Round r =wrinkledY = yellow and y=green

X 6

7 1 3

9 2 5 4

8

What type of cross is this?

Dihybrid

R =Round r =wrinkledY = yellow and y=green

X 6

7 1 3

9 2 5 4

8

What is the genotype of the individual in box 7?RRYy

R =Round r =wrinkledY = yellow and y=green

X 6

7 1 3

9 2 5 4

8

What is the phenotype of the individual in box 8?Wrinkled & green

End of Genetics Part I