Genetics and Heredity

meiosis is necessary in order to ensure that each gamete produced in the human body has -

• 12 chromosomes

• 23 chromosomes

• 46 chromosomes

• 92 chromosomes

what process produces gametes in animals?

• mitosis

• fertilization

• meiosis

• binary fission

select your answer

• 100

• 75

• 50

• 0

In domesticated dogs, hair type is controlled by two different Alleles. The allele for wire hair is (H) and the allele for smooth hair is (h). When two heterozygous dogs are crossed what percentage of the offspring is expected to be homozygous for smooth hair?

• 0

• 25

• 50

• 75

facial dimples and free earlobes are both considered dominant human traits. What are the expected phenotypes of the offspring of a female with dimples and free earlobes (DDFf), and a male with no dimples and attached earlobes (ddff)?

• 50% with dimples and free earlobes and 50% with dimples and attached earlobes

• 50% with dimples and free earlobes and 50% with no dimples and attached earlobes

• 75% with dimples and free earlobes and 25% with no dimples and attached earlobes

• 75% with dimples and attached earlobes and 25% with no dimples and free earlobes

Albinism is an autosomal recessive condition. Which circle graph shows the genotype probability when an albino female mates with a male that is heterozygous for the albinism trait?

• F

• G

• H

• J

normal fruit flies have brownish-yellow bodies, and this body color is dominant. A mutation in the gene for body color can produce flies with an ebony body color. A homozygous normal fruit fly (e+e+) is crossed with a homozygous Ebony fruit fly (ee). What is the predicted outcome of this genetic crosse

• All of the offspring will have ebony bodies

• Of the offspring, 75% will have brownish-yellow bodies, and 25% will have ebony bodies

• All the offspring will have brownish yellow bodies

• Of the offspring, 75% will have ebony bodies and 25% will have brownish-yellow bodies

a genetic cross involving two unlinked genes is represented below. Which genotype is NOT possible in the offspring produced by the cross?

AaGG x aaGg

• AaGG

• Aagg

• aaGg

• aaGG

Mice have two unlinked allele pairs that affect for color. The table shows how allele pairs affect fur color. The term a "agouti" describes fur with pigmentation that changes in each hair from the shaft to the tip, giving the fur a banded appearance. Mice with the aa allele pair are albino, regardless of the second allele-pair combination.

What is the probability of albinism in the offspring of a cross between two mice with alleles?

• 1/16

• 3/16

• 4/16

• 9/16

In the 1860s Gregor Mendel performed numerous dihybrid crosses between pea plants. Dihybrid crosses involve the study of inheritance patterns related to two different traits. In guinea pigs, the allele for black fur (B) is dominant over the allele for brown fur (b), and the allele for short fur (F) is dominant over the allele for long fur (f).

What percentage of the offspring from a BbFf x bbff cross would be expected to be heterozygous for both traits?

• 0

• 25

• 50

• 100