Biology

Question 1

A short pea plant would have to be

Answer 1

Homozygous recessive

Question 2

Recessive traits occur only when an organism is

Answer 2

Homozygous

Question 3

If a female guinea pig homozygous dominant for black fur color is mated with a male the is homozygous recessive for white fur color, in a litter of eight offspring you would expect

Answer 3

8 Black guinea pigs

Question 4

A dogs phenotype can be determined by

Answer 4

Looking at it

Question 5

A couple has two children, both of whom are boys. What is the chance that the parents next child will be a boy?

Answer 5

50%

Question 6

Factors that control traits are called

Answer 6

Genes

Question 7

What does the notation TT mean to geneticists?

Answer 7

2 dominant alleles

Question 8

What does the notation Tt mean to geneticists?

Answer 8

1 dominant allele and 1 recessive allele

Question 9

An organisms physical appearance is its

Answer 9

Phenotype

Question 10

What does the notation tt mean to geneticists?

Answer 10

2 recessive alleles

Question 11

An organisms genotype is its

Answer 11

Genetic makeup

Question 12

An organism that has two identical alleles for each trait is

Answer 12

Homozygous

Question 13

A pet stores customers prefer pet mice with black fur over mice with white fur. With this in mind, the owner crossed a female with black fur and a male with black fur. When the mice were born, she was surprised that three of the ten offspring had white fur. She did not know that the page were heterozygous for fur color. Which letters represent the genotypes of the parents in the above paragraph?

Answer 13

Bb

Question 14

A pet stores owner raises mice, both black and white. Black fur is dominant to white fur. How could the pet store owner breed a litter of only white mice?

Answer 14

By making sure that both the mother and father have white fur

Question 15

If a pet store owner were to cross one homozygous Black mouse with a heterozygous black mouse, what percent of the mice would you expect to have white fur? Work Punnett square on scratch paper

Answer 15

0%

Question 16

Red eyes (R) are dominant in fruit flies, while brown eyes (r) are recessive. If a fruit fly has a homozygous dominant genotype, what color eyes will it have?

Answer 16

Red

Question 17

An organism carries both the dominant and recessive form of a trait. How will the trait be expressed by the organism?

Answer 17

Only the dominant trait will be expressed throughout the organisms life

Question 18

In peas, the color yellow (Y) is dominant to the color green (y). Show a Punnett square crossing two heterozygous plants. What percentage of the offspring of two heterozygous yellow pea plants. What percentage of the offspring of the two heterozygous yellow pea plants will most likely be homozygous green plants? Work on scratch paper.

Answer 18

25%

Question 19

The man who studied inheritance in peas and known as the “Father of Genetics” is

Answer 19

Gregor Mendel

Question 20

A segment of DNA on a chromosome is called a

Answer 20

Gene

Question 21

A cross used to determine the genotype of an individual with a dominant phenotype is

Answer 21

A test cross

Question 22

Assume that brown eyes (B) are dominant over tan eyes (b) in guinea pigs. When a brown-eyed make is mated with a tan-eyed female, 50% of the litter has brown eyes and 50% has tan eyes. What is the genotype of the female guinea pig?

Answer 22

bb

Question 23

A dominant gene that codes for white hair is represented by the symbol W. If a parent with the genotype WW is crossed with a parent of genotype Ww, what percent of their offspring will have white hair? Work your punnett square on scratch paper.

Answer 23

100%

Question 24

Assume that in humans there is a 50/50 chance that a child will be a boy. If a certain mother and father have four sons, what are the chances that their fifth child will be a daughter?

Answer 24

50%

Question 25

In corn plants, ragged leaves (R) are dominant to smooth leaves (r). If two heterozygous ragged leaf plants are crossed, what are the possible genotypes of the offspring? Work your Punnett square on scratch paper.

Answer 25

RR, Rr, rr

Question 26

Sickle cell anemia is a disease that occurs when an individual receives a recessive allele for sickle cell for each parent. Assume that a woman who is a carrier for sickle cell marries a man who is free of the disease. What are the chances of this couple having a child with sickle cell anemia? Work your Punnett square on scratch paper.

Answer 26

0%

Question 27

In pea plants, “tall” is dominant to “short”. To determine if a tall pea plant is heterozygous or homozygous for tallness, it should be crossed with a plant known to be

Answer 27

Homozygous recessive

Question 28

Mendel discovered that in pea plants, the allele for tall plants (T) is dominant to allele for short plants (t). If a homozygous tall pea plant is crossed with a homozygous short pea plant, what will be the genotypes of the offspring? Work your punnett square on your scratch paper.

Answer 28

Tt

Question 29

The tall allele,T, is dominant to the short allele,t, in Mendels pea plants. You examine a pea plant which exhibits a phenotype if tallness. What is the genotype.

Answer 29

It cannot be determined from the information given.

Question 30

After performing a monohybrid cross, it is important to analyze the results of a Punnett square. Each box of punnet square represents

Answer 30

A possible genotype

Question 31

In human genetics, the allele for having freckles in inherited apart from the allele for having attached earlobes. Which one of Mendels principles does this illustrate?

Answer 31

Principle of independent assortment

Question 32

An organism that has one dominant and one recessive allele

Answer 32

Heterozygous

Question 33

An organism that has two dominant or two recessive alleles

Answer 33

Homozygous

Question 34

Characteristics that are inherited

Answer 34

Traits

Question 35

An alternative form of a gene

Answer 35

Allele

Question 36

The likelihood that a particular trait will be inherited in an organism

Answer 36

Probability