Chapter 10: Meiosis and Sexual Life Cycles DSM

A human cell containing 22 autosomes and a Y chromosome is a __________.

sperm

What is a locus?

precise location of a gene on a chromosome

Sister chromatids __________.

are identical copies of each other formed during DNA synthesis

Fertilization produces a __________.

diploid zygote

Which of the following occurs during anaphase II?

Sister chromatids separate and migrate toward opposite poles.

How many genes are present in the human genome?

Tens of thousands

How many different combinations of maternal and paternal chromosomes can be packaged in gametes made by an organism with a diploid number of 8 (2n = 8)?

16

The synaptonemal complex __________.

physically connects homologous chromosomes during prophase I

Spores and gametes differ in that __________.

gametes must fuse to form a zygote and continue development, but each spore can develop into an independent multicellular organisms on its own

Human somatic cells contain __________ set(s) of chromosomes and are therefore termed __________.

two; diploid

In sexually reproducing species, the chromosome number remains stable over time because __________ and __________ always alternate.

meiosis; fertilization

Crossing over occurs during __________.

prophase I

Which event occurs only during prophase I of the first meiotic division?

Synapsis of homologous chromosomes occurs.

Which of the following is included in alternation of generations?

All of the listed responses are correct.

- Multicellular diploid stage (sporophyte)

- Zygote

- Spores

- Multicellular haploid stage (gametophyte)

Which of the following statements best describes the advantage that sexual reproduction likely provides over asexual reproduction?

Although energetically more costly than asexual reproduction, sexual reproduction leads to different combinations of alleles that could provide adaptability in a changing environment.

Synapsis occurs during __________.

prophase I

In a male mammal, every germ cell that undergoes meiosis in the production of gametes gives rise to __________ sperm.

4

Which of the following contributes to genetic variation in sexually reproducing species?

Independent assortment, crossing over, and random fertilization

A karyotype is a __________.

photograph of all of an individual's chromosomes

In a diploid cell containing 10 chromosomes, meiosis results in the formation of daughter cells containing __________ chromosomes.

5

How many pairs of autosomes do humans have?

22

Which of the following human cells contain 46 chromosomes?

liver cells

In a diploid set of chromosomes, one member of each pair of homologous chromosomes is derived from the father (paternal) and the other comes from the mother (maternal). If 2n = 6, what is the probability of obtaining a gamete in which all the chromosomes are paternal ones?

1/8

The egg (ovum) of a rabbit contains 22 chromosomes. How many chromosomes are in the somatic (body) cells of a rabbit?

44

Homologous chromosomes move toward opposite poles of a dividing cell during __________.

meiosis I