biology chapter 12, 13

Which of these phases encompasses all of the stages of mitosis but no other events?

E

Which of the following correctly matches a phase of the cell cycle with its description?

G1: follows cell division

Who loves you more: Niney or Bagel

Idk, only Niney cries

If a cell has completed meiosis I and is just beginning meiosis II, which of the following is an appropriate description of its contents?

It has half the amount of DNA as the cell that began meiosis.

Which of the following phases make up the stages of mitosis?

Prophase, prometaphase, metaphase, anaphase, and telophase

What must happen to a chromosome before a cell starts mitosis?

The single DNA molecule in the chromosome must be replicated.

Homologous chromosomes migrate to opposite poles during _____.

anaphase I

Centromeres split and sister chromatids migrate to opposite poles in meiosis _____.

anaphase II

During _____ sister chromatids separate.

anaphase II

During _____ chromosomes align single file along the equator of a haploid cell.

metaphase II

Sister chromatids separate from each other during _____.

mitosis and meiosis II

During _____ both the contents of the nucleus and the cytoplasm are divided

mitotic phase

G1 is associated with which of the following cellular events?

normal growth and cell function

The first gap in the cell cycle (G1) corresponds to _____.

normal growth and cell function

Spindle fibers attach to kinetochores during _____.

prometaphase

Which processes lead to most genetic variation in sexually reproducing organisms?

-random fertilization -independent assortment of chromosomes in meiosis -crossing over

Which of the following properties is associated with a cyclin-dependent kinase (Cdk)?

A Cdk is an enzyme that attaches phosphate groups to other proteins.

Which of these is NOT a carcinogen?

All are carcinogens: fat testosterone UV light cigarette smoke

For what purpose(s) might a karyotype be prepared?

All three are correct: for prenatal screening, to determine if a fetus has the correct number of chromosomes to determine whether a fetus is male or female to detect the possible presence of chromosomal abnormalities such as deletions, inversions, or translocations

This chromosome has two chromatids, joined at the centromere. What process led to the formation of the two chromatids?

Cannot put image Answer is The two chromatids were formed by duplication of a chromosome.

Which of these gametes contains one or more recombinant chromosomes?

Cannot put image but it is B and C

When homologous chromosomes cross over, what occurs?

Corresponding segments of non-sister chromatids are exchanged.

Which of the following processes occurs when homologous chromosomes cross over in meiosis I?

Corresponding segments of non-sister chromatids are exchanged.

Eukaryotic chromosomes are composed of which of the following macromolecules?

DNA and proteins

Which statement provides the best description of the interphase portion of the cell cycle?

During interphase, a cell is metabolically active.

Cells will usually divide if they receive the proper signal at a checkpoint in which phase of the cell cycle?

G1

Which of the following correctly matches a phase of the cell cycle with its description? See Concept 12.2 (Page 237)

G1: follows cell division

How are sister chromatids and homologous chromosomes different from each other?

Homologous chromosomes contain the same gene loci but may have different alleles of a particular gene. Sister chromatids are identical copies of each other produced during DNA replication.

How are sister chromatids and homologous chromosomes different from each other? See Concept 13.3 (Page 260)

Homologous chromosomes contain the same gene loci but may have different alleles of a particular gene. Sister chromatids are identical copies of each other produced during DNA replication.

Which of the following happens at the conclusion of meiosis I?

Homologous chromosomes of a pair are separated from each other.

The cyclin component of MPF is destroyed toward the end of which phase?

M

Which of the following statements best describes microtubules?

Microtubules are made up of subunits of tubulin, and are structures along which substances are transported in the cell.

What is true of all cancers?

They have escaped normal cell cycle controls.

Why do some species employ both mitosis and meiosis, whereas other species use only mitosis?

They need both if they are producing animal gametes.

Centromeres divide and sister chromatids become full-fledged chromosomes during _____.

anaphase

Many organisms spend most of their life cycle in the diploid state. If meiosis produces haploid cells, how is the diploid number restored for these types of organisms?

by fertilization

The microtubule-organizing center found in animal cells is an identifiable structure present during all phases of the cell cycle. Specifically, it is known as the _____

centrosome

What is the name of the microtubule-organizing center found in animal cells as an identifiable structure present during all phases of the cell cycle?

centrosome

MPF is a dimer consisting of _____.

cyclin and a cyclin-dependent kinase

Which of the following processes occur during meiosis but not mitosis?

diploid cells form haploid cells

Vinblastine is a standard chemotherapeutic drug used to treat cancer. Because it interferes with the assembly of microtubules, its effectiveness must be related to

disruption of mitotic spindle formation.

Heritable variation is required for which of the following?

evolution

_____ is a carcinogen that promotes colon cancer

fat

Meiosis II typically produces _____ cells, each of which is _____.

four, haploid

Independent assortment of chromosomes occurs during _____.

meiosis I only

During _____ the cell grows and replicates both its organelles and its chromosomes.

interphase

Nucleoli are present during _____.

interphase

In some organisms, such as certain fungi and algae, cells undergo the cell cycle repeatedly without subsequently undergoing cytokinesis. What would result from this?

large cells containing many nuclei

Crossing over normally takes place during which of the following processes?

meiosis I

Homologous chromosomes move toward opposite poles of a dividing cell during

meiosis I

Chromosomes become visible during _____.

prophase

Synapsis occurs during _____.

prophase I

During _____ a spindle forms in a haploid cell.

prophase II

Which of the following does NOT occur during mitosis?

replication of the DNA

Which of the following events occurs during interphase of the cell cycle?

replication of the DNA

The mitotic spindle is a microtubular structure that is involved in _____.

separation of sister chromatids

The mitotic spindle plays a critical role in which of the following processes?

separation of sister chromatids

Which of the following occurs during meiosis but not during mitosis?

synapsis occurs

Which of the following occurs in meiosis but not in mitosis?

synapsis of chromosomes

Cytokinesis often, but not always, accompanies _____.

telophase

At the end of _____ and cytokinesis, haploid cells contain chromosomes that each consist of two sister chromatids.

telophase I

At the end of _____ and cytokinesis there are four haploid cells.

telophase II

Which of the following defines a genome?

the complete set of an organism's genes and other DNA sequences

The decline of MPF activity at the end of mitosis is due to

the degradation of cyclin

What is crossing over?

the exchange of homologous portions of nonsister chromatids

During prophase a homologous pair of chromosomes consists of _____.

two chromosomes and four chromatids

Mitosis results in the formation of how many cells; meiosis results in the formation of how many cells?

two diploid cells, four haploid cells

Meiosis I produces _____ cells, each of which is _____.

two, haploid