Question 1

The most accurate description of an organism with genotype AaBb is

Accepted Answer

A)  homozygous dominant. 
B)  heterozygous. 
C)  heterozygous dominant. 
D)  homozygous recessive. 
E)  heterozygous recessive. 
A)  homozygous dominant. 
B)  heterozygous. 
C)  heterozygous dominant. 
D)  homozygous recessive. 
E)  heterozygous recessive.

Question 2

If tall (D) is dominant to dwarf (d) , and two homozygous varieties DD and dd are crossed, then what kind of offspring will be produced?

Accepted Answer

A)  all intermediate forms 
B)  all tall 
C)  all dwarf 
D)  1/2 tall, 1/2 dwarf 
E)  3/4 tall, 1/4 dwarf 
A)  all intermediate forms 
B)  all tall 
C)  all dwarf 
D)  1/2 tall, 1/2 dwarf 
E)  3/4 tall, 1/4 dwarf

Question 3

A gene that produces multiple effects is called

Accepted Answer

A)  a multiple allele. 
B)  an autosome. 
C)  an epistatic gene. 
D)  a pleiotropic gene. 
E)  an incompletely dominant gene. 
A)  a multiple allele. 
B)  an autosome. 
C)  an epistatic gene. 
D)  a pleiotropic gene. 
E)  an incompletely dominant gene.

Question 4

If you were following the inheritance patterns of two different sets of multiple alleles located on different chromosomes, how many different possible gametes could be produced if locus 1 had five possible alleles and locus 2 had six alleles?

Accepted Answer

The answer of If you were following the inheritance patterns...

Question 5

When an allele can produce a range of phenotypes, its expression is said to be

Accepted Answer

A)  clearly established. 
B)  variable. 
C)  codominant. 
D)  incompletely dominant. 
E)  incompletely penetrant. 
A)  clearly established. 
B)  variable. 
C)  codominant. 
D)  incompletely dominant. 
E)  incompletely penetrant.

Question 6

The genotype AA is referred to as

Accepted Answer

A)  heterozygous. 
B)  hybrid. 
C)  homozygous recessive. 
D)  homozygous dominant. 
E)  codominant. 
A)  heterozygous. 
B)  hybrid. 
C)  homozygous recessive. 
D)  homozygous dominant. 
E)  codominant.

Question 7

Observable functional or physical traits are the

Accepted Answer

A)  phenotype. 
B)  allelotype. 
C)  homotype. 
D)  heterotype. 
E)  genotype. 
A)  phenotype. 
B)  allelotype. 
C)  homotype. 
D)  heterotype. 
E)  genotype.

Question 8

In cocker spaniels, black coat color (B) is dominant over red (b) , and solid color (S) is dominant over spotted (s) . If Bb Ss were crossed with Bb ss , the chance that a black, solid individual would be produced is

Accepted Answer

A)  3/16. 
B)  1/3. 
C)  9/16. 
D)  3/8. 
E)  1/16. 
A)  3/16. 
B)  1/3. 
C)  9/16. 
D)  3/8. 
E)  1/16.

Question 9

What fraction of the time will the cross of Aa Bb Cc with Aa Bb Cc produce an offspring that expresses all three dominant genes?

Accepted Answer

A)  3/64 
B)  1/16 
C)  1/8 
D)  9/64 
E)  27/64 
A)  3/64 
B)  1/16 
C)  1/8 
D)  9/64 
E)  27/64

Question 10

A cross of two Kerry horses always produces Kerry. A cross of a Kerry with a Dexter horse produces 1/2 and 1/2. Crosses of two Dexters produce two Dexters for every Kerry. Explain.

Accepted Answer

Kerry is homozygous

Question 11

What fraction of the time will the cross of Aa Bb Cc with Aa Bb Cc produce an offspring that expresses the phenotype represented by the dominant gene C ( aa bb C_) ?

Accepted Answer

A)  1/32 
B)  3/64 
C)  1/16 
D)  9/64 
E)  27/64 
A)  1/32 
B)  3/64 
C)  1/16 
D)  9/64 
E)  27/64

Question 12

In the garden pea, Mendel found that tall ( D ) green pods ( G ) and inflated pods ( C ) were dominant to their alleles, dwarf ( d ) yellow pods ( g ), and constricted pods ( c ). Given the following genotypes, determine the chances of producing the offspring shown. 
 (a) DD Gg Cc x Dd Gg cc → DD gg Cc 
 (b) DD Gg Cc x Dd Gg Cc → tall green pod, constricted pod 
 (c) Dd Gg Cc x Dd GG cc → tall green pod, inflated pod 
 (d) Dd Gg Cc x Dd Gg Cc → D _ G _ cc 
 (e) Dd Gg Cc x Dd gg CC → D _ G _ C _ 
 (f) Dd gg cc x DD Gg cc → tall green pod, inflated pod 
 (g) Dd Gg Cc x Dd Gg Cc → Dd Gg Cc 
 (h) Dd Gg Cc x Dd Gg Cc → dd gg cc

Accepted Answer

(a) (1/2) (1/4) (1/2) = 1/16 
 (b) (1) (

Question 13

The genotype Aa is referred to as

Accepted Answer

A)  heterozygous. 
B)  incompletely dominant. 
C)  homozygous recessive. 
D)  homozygous dominant. 
E)  codominant. 
A)  heterozygous. 
B)  incompletely dominant. 
C)  homozygous recessive. 
D)  homozygous dominant. 
E)  codominant.

Question 14

If a woman of blood type A has a child of blood type O, the father may belong to
A) blood types A, AB, or O, but not B.
B) blood type O only.
C) blood types A, B, or O, but not AB.
D) any blood type other than type A.
E) blood type A only.

Accepted Answer

The answer of If a woman of blood type A...

Question 15

Pleiotropic genes

Accepted Answer

A)  act on secondary sexual characteristics. 
B)  influence more than one aspect of phenotype. 
C)  are additive. 
D)  produce lethal effects when homozygous. 
E)  cannot be inherited. 
A)  act on secondary sexual characteristics. 
B)  influence more than one aspect of phenotype. 
C)  are additive. 
D)  produce lethal effects when homozygous. 
E)  cannot be inherited.

Question 16

A testcross involves

Accepted Answer

A)  two F 1 hybrids. 
B)  an F 1 hybrid and an F 2 offspring. 
C)  two parental organisms. 
D)  an F 1 hybrid and the homozygous dominant parent. 
E)  an F 1 hybrid and an organism that is homozygous recessive for that trait. 
A)  two F 1 hybrids. 
B)  an F 1 hybrid and an F 2 offspring. 
C)  two parental organisms. 
D)  an F 1 hybrid and the homozygous dominant parent. 
E)  an F 1 hybrid and an organism that is homozygous recessive for that trait.

Question 17

If short hair (L) is dominant to long hair (l) , then to determine the genotype of a short-haired animal it should be crossed with

Accepted Answer

A)  LL . 
B)  Ll . 
C)  ll . 
D)  all of these. 
E)  none of these. 
A)  LL . 
B)  Ll . 
C)  ll . 
D)  all of these. 
E)  none of these.

Question 18

When a population shows a range of nonincremental differences in some trait, they are showing

Accepted Answer

A)  continuous variation. 
B)  pleiotropy. 
C)  linear variation. 
D)  exponential variation. 
E)  skewed variation. 
A)  continuous variation. 
B)  pleiotropy. 
C)  linear variation. 
D)  exponential variation. 
E)  skewed variation.

Question 19

If short hair (L) is dominant to long hair (l) , then what fraction of the offspring produced by a cross of Ll x ll will be homozygous dominant?

Accepted Answer

A)  1/2 
B)  1/4 
C)  1/3 
D)  0 
E)  2/4 
A)  1/2 
B)  1/4 
C)  1/3 
D)  0 
E)  2/4

Question 20

In cultivated stocks, the cross of a variety of white flower plants produced all red flowers in the F 1 generation, but the F 2 generation produced 87 red flowers, 31 cream flowers, and 39 white flowers. Explain these results by giving the genotypes possible for each phenotype.

Accepted Answer

R -red, r -cream, A

Exam 19: Introduction to Genetics

The most accurate description of an organism with genotype AaBb is

If tall (D) is dominant to dwarf (d) , and two homozygous varieties DD and dd are crossed, then what kind of offspring will be produced?

A gene that produces multiple effects is called

If you were following the inheritance patterns of two different sets of multiple alleles located on different chromosomes, how many different possible gametes could be produced if locus 1 had five possible alleles and locus 2 had six alleles?

When an allele can produce a range of phenotypes, its expression is said to be

The genotype AA is referred to as

Observable functional or physical traits are the

In cocker spaniels, black coat color (B) is dominant over red (b) , and solid color (S) is dominant over spotted (s) . If Bb Ss were crossed with Bb ss , the chance that a black, solid individual would be produced is

What fraction of the time will the cross of Aa Bb Cc with Aa Bb Cc produce an offspring that expresses all three dominant genes?

A cross of two Kerry horses always produces Kerry. A cross of a Kerry with a Dexter horse produces 1/2 and 1/2. Crosses of two Dexters produce two Dexters for every Kerry. Explain.

What fraction of the time will the cross of Aa Bb Cc with Aa Bb Cc produce an offspring that expresses the phenotype represented by the dominant gene C ( aa bb C_) ?

The genotype Aa is referred to as

If a woman of blood type A has a child of blood type O, the father may belong to A) blood types A, AB, or O, but not B. B) blood type O only. C) blood types A, B, or O, but not AB. D) any blood type other than type A. E) blood type A only.

Pleiotropic genes

A testcross involves

If short hair (L) is dominant to long hair (l) , then to determine the genotype of a short-haired animal it should be crossed with

When a population shows a range of nonincremental differences in some trait, they are showing

If short hair (L) is dominant to long hair (l) , then what fraction of the offspring produced by a cross of Ll x ll will be homozygous dominant?

In cultivated stocks, the cross of a variety of white flower plants produced all red flowers in the F 1 generation, but the F 2 generation produced 87 red flowers, 31 cream flowers, and 39 white flowers. Explain these results by giving the genotypes possible for each phenotype.

Learning About Human Biology

Chemistry of Life

Cells and How They Work

Tissues, Organs, and Organ Systems

The Skeletal System

The Muscular System

Circulation: the Heart and Blood Vessels

Blood

Immunity and Disease

The Respiratory System

Digestion and Nutrition

The Urinary System

The Nervous System

Sensory Systems

The Endocrine System

Reproductive Systems

Development and Aging

Cell Reproduction

Chromosomes and Human Genetics

DNA, Genes, and Biotechnology

Genes and Disease: Cancer

Principles of Evolution

Principles of Ecology

Human Impacts on the Biosphere

Filters

In cultivated stocks, the cross of a variety of white flower plants produced all red flowers in the F ₁ generation, but the F ₂ generation produced 87 red flowers, 31 cream flowers, and 39 white flowers. Explain these results by giving the genotypes possible for each phenotype.