Chpt 12

Assume that you are dealing with a species in which the number of chromosomes in each somatic cell is 14. How many sister chromatids are present in the early telophase of mitosis? (eText Concept 12.2) 0 7 14 28 None of the listed responses is correct.

0

A cell biologist carefully measured the quantity of DNA in grasshopper cells growing in cell culture. Cells examined during the G2 phase of the cell cycle contained 200 units of DNA. What would be the amount of DNA at G1 of the cell cycle in one of the grasshopper daughter cells? (eText Concept 12.2) 50 units 100 units between 50 and 100 units 200 units 400 units

100 units

How many maternal chromosomes are present in a somatic human cell not engaged in cell division? (eText Concept 12.1) 23 46 92 184 None of the listed responses is correct.

23; each somatic cell has 46 chromosomes and only half are maternal

If a cell contains 60 chromatids at the start of mitosis, how many chromosomes will be found in each daughter cell at the completion of the cell cycle? (eText Concept 12.2) 15 30 45 60 120

30

Open Hint for Question 16 in a new window If a human somatic cell is just about to divide, it has __________ chromatids. (eText Concept 12.2) 0 23 46 92 There is insufficient information to answer the question.

92

Down syndrome is characterized by cells having three copies of chromosome 21. As a cell in an individual with Down syndrome prepares to enter mitosis, how many chromatids would be present? (eText Concept 12.2) 23 46 92 94 98

94

When a cell in S phase is fused with a cell in G1, __________. (eText Concept 12.3) DNA synthesis begins immediately in the original G1 nucleus the two nuclei fuse and additional division is arrested the chromosomes of the original G1 nucleus condense in preparation for mitosis the replication of DNA occurring in the original S nucleus is terminated the original G1 cell will divide immediately

DNA synthesis begins immediately in the original G1 nucleus

A particular cell has half as much DNA as some other cells in a mitotically active tissue. The cell in question is most likely in metaphase. G1. prophase. anaphase. G2.

G1

During what phase in the cell cycle would you find the most DNA per cell? (eText Concept 12.2) S G2 G0 G1 S1

G2

The person credited with first recognizing (in the 1860s) that living cells cannot arise spontaneously, but arise only from previously existing cells, is __________. (eText Overview) Rudolf Virchow Watson Anton van Leeuwenhoek Louis Pasteur Robert Hooke

Rudolf Virchow

Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on either side of the cell plate. This cell is most likely an animal cell in the process of cytokinesis. a bacterial cell dividing. a plant cell in metaphase. an animal cell in the S phase of the cell cycle. a plant cell in the process of cytokinesis.

a plant cell in the process of cytokinesis

Which event or events occur during anaphase? (eText Concept 12.2) The centrioles are at opposite poles during anaphase. A spindle made of microtubules is present during anaphase. Cohesins joining sister chromatids at the centromeres are cleaved during anaphase. Genetically identical chromosomes (previously sister chromatids) move to opposite poles during anaphase. All of the listed responses are correct.

all of the listed responses

During which stage of the cell cycle do sister chromatids separate? (eText Concept 12.2) anaphase G1 phase prophase metaphase G2 phase

anaphase

The phase of mitosis during which the chromosomes move toward separate poles of the cell is __________. (eText Concept 12.2) prophase telophase anaphase metaphase prometaphase

anaphase

The function of the mitotic cell cycle is to produce daughter cells that __________. (eText Concept 12.1) have the same number of chromatids as the parent cell had chromosomes have the same number of chromosomes as the parent cell but not the same genetic content have a random assortment of maternal and paternal chromosomes are genetically identical to the parent cell (assuming no mutation has occurred) have none of the listed characteristics

are genetically identical to the parent cell (assuming no mutation has occurred)

A biochemist measured the amount of DNA in cells growing in the laboratory and found that the quantity of DNA in the cells doubled __________. (eText Concept 12.2) between prophase and anaphase between the G2 phase and prophase during the M phase of the cell cycle between anaphase and telophase between the G1 and G2 phases

between the G1 and G2 phases

Which of the following is FALSE regarding sister chromatids? (eText Concept 12.1) Sister chromatids form in the S-phase stage of the cell cycle. Sister chromatids are separated during mitosis. Sister chromatids are created when DNA is replicated. Sister chromatids are attached to one another at the centromere. Both of the sister chromatids end up in the same daughter cell after cytokinesis has occurred.

both of the sister chromatids end up in the same daughter cell after cytokinesis has occurred

What is the difference between a benign tumor and a malignant tumor? (eText Concept 12.3) Benign tumors do not arise by transformation; malignant tumors do. Benign tumors arise by transformation; malignant tumors do not. Cells of benign tumors metastasize; those of malignant tumors do not. Benign tumors will not kill you; malignant tumors will. Cells of benign tumors do not metastasize; those of malignant tumors do

cells of benign tumors don't metastasize: those of malignant tumors do

In the cells of some organisms, mitosis occurs without cytoki-nesis. This will result in cells that are unusually small. destruction of chromosomes. cell cycles lacking an S phase. cells lacking nuclei. cells with more than one nucleus.

cells with more than one nucleus

The region of a chromosome in which the two double strands of replicated DNA are held together is called __________. (eText Concept 12.1) a centromere an aster a chromatid a centriole chromatin

centromere

The complex of DNA and protein that makes up a eukaryotic chromosome is properly called __________. (eText Concept 12.1) chromatin a centromere a centrosome a chromoplast a chromatid

chromatin

The drug cytochalasin B blocks the function of actin. Which of the following aspects of the animal cell cycle would be most disrupted by cytochalasin B? DNA synthesis cell elongation during anaphase cleavage furrow formation and cytokinesis spindle formation spindle attachment to kinetochores

cleavage furrow formation and cytokinesis

One difference between cancer cells and normal cells is that cancer cells are unable to synthesize DNA. are always in the M phase of the cell cycle. cannot function properly because they are affected by density-dependent inhibition. are arrested at the S phase of the cell cycle. continue to divide even when they are tightly packed together.

continue to divide even when they are tightly packed together

In animal cell mitosis, the cleavage furrow forms during which stage of the cell cycle? (eText Concept 12.2) anaphase cytokinesis the G1 phase metaphase prophase

cytokinesis

During interphase, the genetic material of a typical eukaryotic cell is __________. (eText Concept 12.2) dispersed in the nucleus as long strands of chromatin dispersed in the cytoplasm as long strands of chromatin attached to microtubule spindle fibers transported through the nuclear pores condensed and the chromosomes are often visible under the light microscope

dispersed in the nucleus as long strands of chromatin

Vinblastine is a standard chemotherapeutic drug used to treat cancer. Because it interferes with the assembly of micro-tubules, its effectiveness must be related to suppression of cyclin production. inhibition of regulatory protein phosphorylation. inhibition of DNA synthesis. myosin denaturation and inhibition of cleavage furrow formation. disruption of mitotic spindle formation.

disruption of mitotic spindle formation

Which of the following is involved in the binary fission of most bacteria? (eText Concept 12.2) formation of a spindle apparatus prophase, prometaphase, metaphase, anaphase, and telophase formation of a cell plate distribution of a copy of the single parental chromosome to each daughter cell disintegration of the nuclear membrane

distribution of a copy of the single parental chromosome to each daughter cell

Tissue culture experiments with PDGF demonstrate that without this substance __________. (eText Concept 12.3) bacterial cells lose their resistance to antibiotics fibroblasts fail to divide the various kinases, such as MPF, are unable to bind to cyclin cells divide in an uncontrolled fashion, confirming PDGF's role as a cell division inhibitor animal cells are unable to attach to the substratum

fibroblasts fail to divide

Chromatids are __________. (eText Concept 12.1) composed of RNA found only in aberrant chromosomes the bacterial equivalent of eukaryotic chromosomes identical copies of each other if they are part of the same duplicated chromosome held together by the centrioles

identical copies of each other if they are part of the same duplicated chromosome

You would know that a dividing cell was a plant cell rather than an animal cell if you saw that __________. (eText Concept 12.2) it had formed a cell plate it had microtubules it had two pairs of centrioles during prophase it had formed a cleavage furrow the nucleolus was visible during metaphase

it had formed a cell plate

At which stage of mitosis are chromosomes lined up in one plane in preparation for their separation to opposite poles of the cell? (eText Concept 12.2) interphase prophase metaphase telophase anaphase

metaphase

Which of the following represents a mismatch or incorrect description? (eText Concept 12.2) metaphase: the nuclear envelope disappears prophase: chromosomes become more tightly coiled metaphase: chromosomes line up on the equatorial plane anaphase: there is movement of the chromosomes to the poles telophase: chromosomes become more extended

metaphase: the nuclear envelope disapears

Which of the following processes does NOT occur in dividing bacteria? (eText Concept 12.2) separation of the origins of replication replication of DNA binary fission mitosis inward growth of the plasma membrane

mitosis

You would be UNLIKELY to see which of the following human cells dividing? (eText Concept 12.3) nerve cell cell from an embryo skin cell cancer cell All of these cell types are equally unlikely to divide at any given time.

nerve cell

A cell entering the cell cycle with 32 chromosomes will produce two daughter cells, each with __________. (eText Concept 12.1) 16 chromosomes 64 chromosomes 32 pairs of chromosomes 64 pairs of chromosomes none of the listed numbers of chromosomes

none of the listed numbers

In a human skin cell that is going through the cell cycle, when do the centrosomes separate? (eText Concept 12.2) metaphase prophase anaphase S phase G2 phase

prophase

In telophase of mitosis, the mitotic spindle breaks down and the chromatin uncoils. This is essentially the opposite of what happens in __________. (eText Concept 12.2) S phase metaphase anaphase interphase prophase

prophase

Which of the following does not occur during mitosis? replication of the DNA separation of sister chromatids spindle formation condensation of the chromosomes separation of the spindle poles

replication of DNA

Which of the following does NOT occur during mitosis? (eText Concept 12.2) separation of chromatids the movement of chromosomes to opposite poles condensation of chromatin alignment of chromosomes along the cell's equator replication of chromosomes

replication of chromosomes

The centromere is a region in which __________. (eText Concept 12.1) microtubules are fastened to the centrioles during anaphase chromosomes become aligned during metaphase the new cell plate forms in telophase the chromosomes are connected to the cell plate in metaphase sister chromatids are attached to one another in prophase

sister chromatids are attached to one another in prophase

Which of the following phases of mitosis is essentially the OPPOSITE of prometaphase in terms of the nuclear envelope? (eText Concept 12.2) S phase metaphase interphase telophase anaphase

telophase

DNA replication occurs in __________. (eText Concept 12.2) cytokinesis metaphase of mitosis the S phase of interphase the G1 phase of interphase prophase of mitosis

the S phase of interphase

One event occurring during prophase is __________. (eText Concept 12.2) the synthesis of a new nuclear envelope the division of the centromere the beginning of the formation of a spindle apparatus the alignment of chromosomes in a single plane cytokinesis

the beginning of the formation of a spindle apparatus

Which of the following hypotheses is best supported by observing cancer cells in a culture?(eText Concept 12.3) The cancer cells produce molecules that inhibit the growth factors required for cell division. The cancer cells spend the majority of their time in the G0 phase. The cancer cells exhibit anchorage dependence. The cancer cells do not exhibit density-dependent inhibition. All of the listed responses are correct.

the cancer cells don't exhibit density-dependent inhibition

The decline of MPF activity at the end of mitosis is due to the accumulation of cyclin. decreased synthesis of Cdk. the degradation of cyclin. the destruction of the protein kinase Cdk. synthesis of DNA. End of Question 4 Question 5

the degradation of cyclin

"Cytokinesis" refers to __________. (eText Concept 12.1) the reduction in the number of chromosomes the division of the nucleus the movement of a cell from one place to another the division of the entire cell the division of the cytoplasm

the division of cytoplasm

During binary fission in a bacterium, __________. (eText Concept 12.2) the two DNA molecules float free in the cell and are guided to daughter cells by a spindle-like apparatus the two DNA molecules attach to the centrioles the origins of replication move apart the two DNA molecules break up into plasmids the two DNA molecules divide in half, forming four DNA fragments

the origins of replication move apart

Following cytokinesis in an animal cell, how many centrioles does each new daughter cell possess? (eText Concept 12.2) zero one two four eight

two