Ch. 12-15

Immature cells that can divide and differentiate into specialized cells are called

stem cells

Predict the sex of two babies, the first with an XXY pair of sex chromosomes and the second with an X sex chromosome. (Baby #1 and baby #2) a. #1: male, #2: female b. #1: female, #2: male c. cannot determine with the chromosome information given d. both females e. both males

1: male, 2: female

Write in the normal chromosome number? (numerical value) a human egg: _____; a human sperm: _____; a human zygote:_____

23; 23; 46

If a man has an X-linked recessive disease, can his sons inherit that disease from him?

No, all sons inherit X chromosomes maternally

How are polygenic and multifactorial traits different? a. Polygenic traits are influenced by nutrition and diet, whereas multifactorial traits are not. b. Polygenic traits are genetically based, whereas multifactorial traits have both genetic and environmental influences. c. Polygenic traits are influenced by the number of traumatic life events, whereas multifactorial traits are influenced by the levels of brain chemicals. d. Polygenic traits show a continuous range of phenotypic variation, whereas multifactorial traits show several distinct phenotypes. e. There are more kinds of polygenic traits than multifactorial traits

Polygenic traits are genetically based, whereas multifactorial traits have both genetic and environmental influences.

Are males more affected by X-linked recessive genetic diseases than females? Why?

Yes, because females have an additional X chromosome to mask X-linked recessive alleles -Y chromosome does not represent the same alleles, and cannot mask X-linked recessive alleles

Inbreeding a. changes the allele frequency within a population b. does not change the allele frequency within a population c. increases the proportion of homozygous individuals to heterozygous individuals d. a and c e. b and c

a and c

The response of a population to environmental pressure so that advantageous traits become more common in the population over time

adaptation

Stem cells located in tissues that help maintain and regulate those tissues are called

adult and somatic stem cells

Stem cells in tissue can divide to produce: a. more stem cells b. specialized cells c. specialized cells that make up tissues d. The first two answers are correct e. All of the above

all of the above

A gamete is aneuploid if __________. a. one or more homologous chromosomes fail to separate in meiosis I b. one or more sister chromatids fail to separate in meiosis II c. there are more than 23 chromosomes in the cell d. there are fewer than 23 chromosomes in the cell e. All of the above are true

all of the above are true

Beta-lactam antibiotics interfere with bacteria's ability to synthesize

cell walls

The process by which a cell specializes to carry out a specific role is called

cellular differentiation

The evolution of antibiotic resistance is an example of:

directional selection

The type of natural selection in which organisms with phenotypes at one end of the spectrum are favored by the environment

directional selection

A type of natural selection in which organisms with phenotypes at both extremes of the phenotypic range are favored by the environment

diversifying selection

Different environments are responsible for a. ecological isolation b. reproductive isolation c. temporal isolation d. behavioral isolation e. mechanical isolation

ecological isolation

The change in allele frequencies in a population over time

evolution

The relative ability of an organism to survive and reproduce in a particular environment

fitness

There are two populations of trout in a town, both of which inhabit a different lake. These lakes are connected by a stream, and trout from these two populations are able to breed with one another. This is an example of which of the following? a. gene flow b. genetic drift c. the bottleneck effect d. the founder effect e. None of the above

gene flow

The total collection of alleles in a population is the

gene pool

Random changes in the allele frequency of a population between generations is the definition of

genetic drift

The negative reproductive consequences for a population associated with having a high frequency of homozygous individuals possessing harmful recessive alleles is

inbreeding depression

Which of the following inheritance patterns includes an environmental contribution? a. polygenic b. X-linked recessive c. X-linked dominant d. multifactorial e. none of the above

multifactorial

_____ describes a cell with the ability to differentiate into nearly any cell type in the body

pluripotent

A group of organisms of the same species living together in the same geographic area

population

What term refers to mechanisms that prevent mating (and therefore gene flow) between members of different species? a. ecological isolation b. reproductive isolation c. temporal isolation d. behavioral isolation e. mechanical isolation

reproductive isolation

Members of a population that interbreed and produce fertile offspring a. species b. animals c. individuals d. The first two are correct e. All of the above

species

A type of natural selection in which organisms near the middle of the phenotypic range of variation are favored

stabilizing selection

In humans, very-large-birth-weight babies and very tiny babies do not survive as well as midrange babies. What kind of selection is acting on human birth weight?

stabilizing selection

What is the Y chromosome commonly used for?

to determine paternity and anscetry

____ describes a cell with the ability to differentiate into any cell type in the body?

totipotent