Mendel verified true-breeding pea plants for certain traits before undertaking his experiments. The term "true-breeding" refers to:

genetically pure lines

the physical appearance of an organism for a given trait is termed:

phenotype

The term dominant means that:

one allele can mask the expression of another in a hybrid

_______ are alternative forms of a gene that govern the same feature, such as eye color, and occupy corresponding positions on homologous chromosomes

alleles

Mendel's principle of segregation states that:

alleles separate from each other before forming gametes

Using standard conventions for naming alleles, which of the following pairs is correct?

tt-homozygous

A pear plant with the genotype Aa can produce gametes containing:

either A or a

The physical location of a particular gene on a chromosome is called:

a locus

Which of the following represents the possible genotypes resulting from a cross between an individual homozygous BB and one heterozygous Bb individual

BB and Bb

Which of the following represents the possible genotypes resulting from a cross between two individuals that are heterozygous Bb?

BB,Bb, and bb

Which of the following represents the possible genotypes resulting forma cross between on individual heterozygous Bb and one that is homozygous bb

Bb and bb

Mating an individual expressing a dominant phenotype, but whose genotype is unknown, with an individual expressing the corresponding recessive phenotype is an example of:

a test cross

The genotype for a pea plant that is homozygous recessive for both height and pea color would be:

ttyy

In peas, Mendel found that tall plants and yellow peas are dominant. Short plants and green peas are recessive. The phenotype for a pea plant with the genotype TTyy would be:

tall with green peas

In peas, Mendel found that tall plants and yellow peas are dominant. Short plants and green peas are recessive. The phenotype for a pea plant with the genotype TtYy would be:

tall with yellow peas

The height of pea plants from a cross between parent plants heterozygous for height, in which tall is dominant, would be:

3 tall:1 short

Which of the following represents the possible genotype(s) resulting from a cross between an individual homozygous for black hair (BB) and an individual homozygous for blonde hair (bb)?

Bb only

What is the probability that two lizards that are heterozygous for stripes on their tails (Ss) will produce an offspring that is homozygous for no stripes (ss)?

1/4

In humans, assume that the allele for brown eyes is dominant and the allele for blue eyes is recessive. If two brown-eyed individuals have a child with blue eyes, that means:

both parents are heterozygous for eye color

If a couple is planning on having two children, what is the probability that both will be male?

1/4

If a couple is planning on having three children, what is the probability that they will have two girls and one boy? (They can be born in any order, GGB, GBG, BGG.)

3/8

A brown-eyed couple already has a child with blue eyes. What is the probability that their next child will have blue eyes, assuming that the brown eye allele is dominant and the blue eye allele is recessive?

1/4

A couple’s first child was a girl with cystic fibrosis. What is the chance that their next child will normal and male?

1/8

A brown-eyed couple heterozygous for eye color are planning on having two children. What is the probability that both children will have blue eyes, assuming brown eyes is dominant and blue eyes is recessive?

1/16

Two Martians fall in love and marry. One Martian is homozygous for red eyes and the other is heterozygous. The recessive eye color is purple. What is the probability that they will have a child with purple eyes?

0

Two Martians fall in love and marry. One Martian is homozygous for red eyes and the other is heterozygous. The recessive eye color is purple. What are the chances that the alien couple will have a child with red eyes?

1

The principle of independent assortment is not true for:

linked genes

Genes that tend to be inherited together are said to be:

linked

A __________ is best used to demonstrate the linkage of two genes.

two-point test cross

An organism with the genotype of AaXx can produce gametes containing __________ if the two genes are unlinked.

either AX,Ax,aX,ax

The offspring of two heterozygous gray-bodied, normal-winged flies should be 50% gray-bodied/normal wings (BbRr) and 50% black-bodied/vestigial wings (bbrr) because these alleles are linked. If a small number, say 15%, of the offspring are instead black-bodied with normal wings, this is most likely the result of:

crossing over

The probability that two genes will be separated by crossing-over is related to:

the distance between the two genes on the chromosome

In genetics, map units express the distance between:

two loci on a chromosome

The sex of most mammals, birds, and insects is determined by:

sex chromosome

The sex of a human is determined by:

the presence or absence of a Y chromosome

Why is color-blindness more common in males than in females?

Bc the male only needs to receive to recessive gene from his mother to be color blind

What are the possible genotypes of a female child from the union of a woman who is heterozygous for hemophilia and a man who has normal blood clotting characteristics? (Hemophilia is an X-linked recessive disorder.)

XHXH or XHXh

What are the predicted phenotypes of the male children from the union of a woman who is heterozygous for hemophilia and a man who has normal blood clotting characteristics? (Hemophilia is an X-linked recessive disorder.) (Use a Punnett square to verify your answer.)

1 hemophilia : 1 normal

What are the predicted phenotypes of the female children from the union of a woman who is heterozygous for hemophilia and a man who has normal blood clotting characteristics? (Hemophilia is an X-linked recessive disorder.) (Use a Punnett square to verify your answer.)

All hemophiliac

A Barr body in a mammalian female cell represents:

an inactivated X chromosome

Calico cats are never male because:

two different X chromosomes are needed for the expression of the calico phenotype

When certain medium height hybrid plants were crossed, they produced offspring that were dwarf, medium, and tall in a ratio of 1 : 2 : 1. This is an example of:

incomplete dominance

What are the possible phenotypes of the children if the mother has Type A blood and the father has type AB blood? (Use a Punnett square to verify your answer.)

A,B,AB

What are the possible phenotypes of the children if the mother's genotype is I^Ai for blood type and the father is I^Bi? (Use a Punnett square to verify your answer.)

A,B,AB,O

A diploid individual has a maximum of __________ different alleles for a particular locus.

two

A particular gene that controls seed coat color in peas also determines the susceptibility of these peas to a particular disease. This situation is referred to as:

pleiotropy

Breeding a yellow dog with a brown dog produced puppies with both yellow and brown hairs intermixed. This is an example of:

codominance

A gene that affects, prevents, or masks the expression of a gene at another locus is a(n) __________ gene.

epistatic

__________ refers to multiple independent pairs of genes having similar and additive effects on the same characteristic.

Polygenic inheritance

The range of phenotypic possibilities that can develop from a certain dog genotype under different environmental conditions is called the:

norm of reaction