Bio Ch. 8 Quiz

Rick has a high incidence of cancer in his family. Four of the following five statements are preventative measures to avoid cancer. Which of the following is not correct?

Avoid a high-fiber, low-sodium diet.

A woman inherits a mutant BRCA1 allele from her mother. She has an increased risk of developing breast cancer because

a mutation in her normal BRCA1 allele may lead to cancer, whereas a normal individual would have to acquire two mutations (one in each allele) to develop cancer.

Proteins that are involved in the regulation of the cell cycle, and that show fluctuation in concentration during the cell cycle, are called

cyclins.

DNA and histones form bead-like globules known as

nucleosomes.

The spindle serves two roles in mitotic cell division. These are to separate the

sister chromatids and to elongate the cell.

The term metastasis refers to the fact that cancer cells tend to

spread.

A proto-oncogene differs from a tumor suppressor gene because a proto-oncogene

stimulates mitosis in a normal cell, whereas a tumor suppressor gene inhibits mitosis.

All of the following occur during the latter stages of mitotic prophase except the

synthesis of DNA.

Embryonic cells and cancer cells are similar because

telomerase is active.

Ben was looking at onion root tip cells under the microscope in biology class. He saw one cell that had two nuclei within it. What stage of the cell cycle was this cell in?

telophase/cytokinesis

The G2 checkpoint prevents the cell cycle from continuing until

DNA is completely replicated and damage to DNA can be repaired.

A cell is inhibited during the S phase of its cycle. It will not reproduce due to lack of

DNA synthesis.

Inheritance of mutant forms of some genes may lead to a predisposition to develop cancer. Which of the genes listed below has not been linked to hereditary forms of cancer?

DScam

If a cell has 46 chromosomes at the beginning of mitosis, then at the end of anaphase there would be a total of

92 chromosomes

A group of cells is assayed for DNA content immediately following mitosis and is found to have an average of 8 picograms of DNA in the nucleus. Those cells would have ________ picograms at the end of the S phase and ________ picograms at the end of G2.

16; 16

Which of the following organelles would be abundant and in close proximity to the cell plate in a plant cell undergoing cytokinesis?

Golgi apparatus

Cytokinesis usually, but not always, follows mitosis. If a cell undergoes mitosis and not cytokinesis, this would result in

If a cell goes through mitosis but not cytokinesis, it will have two nuclei within one cell.

Which of the following statements is correct regarding the events of the cell cycle?

Interphase consists of G1, S, and G2.

Which of the following represents the phases of mitosis in their proper sequence?

Mitosis is the division of the nucleus; the stages are prophase, metaphase, anaphase, and telophase.

Susan went to an oncologist because some cancerous cells had been detected within her breast tissue. Which of the following is not a warning signal for cancer?

Some cells were found to be in interphase.

A tumor suppressor gene undergoes a mutation that causes it to lose its normal function. What would be the most likely result of this mutation?

The cell no longer responds to signals that cause it to stop dividing or undergo apoptosis.

A mutation results in a cell that no longer produces a normal protein kinase for the M-phase checkpoint. Which of the following would likely be the immediate result of this mutation?

The cell would never leave metaphase.

Cells grown in a petri dish tend to divide until they form a thin layer covering the bottom of the dish. If cells are removed from the middle of the dish, the cells bordering the open space will begin dividing until they have filled the empty space. What does this experiment show?

The cells continued to grow as long as there was empty space. When cells come into contact with other cells they would stop growing, or be turned off.

How do the daughter cells at the end of mitosis and cytokinesis compare to their parent cell when it was in G1 of the cell cycle?

The daughter cells have the same number of chromosomes and the same amount of DNA.

Apoptosis

can be used to remove damaged or malfunctioning cells.

Which of the following is not a characteristic of cancer cells?

cells that spend 90% of their lifetime in interphase

The looping of DNA around histone proteins

condenses a large amount of DNA so that it can fit into the cell.

A mutation that causes an increase in function in a tumor suppressor gene would not likely cause cancer because a tumor suppressor protein

does not promote cell division.

When during the cell cycle are chromosomes visible?

during mitosis

Which of the following is not a characteristic of cancer cells?

exhibit contact inhibition

Multicellular organisms undergo mitotic cell division to

increase the size of the organism.

While Jeff was looking under the microscope at cells in different stages of mitosis, he commented on the fact that many cells were in the same stage. If you were looking under the compound light microscope at an onion root tip, in what stage of the cell cycle would the majority of the cells be?

interphase

Some multicellular organisms, like the hydra, use asexual reproduction to produce a bud that leads to a new organism. This means that they are using

mitotic division to create new cells that become a new organism.

Cells that do not receive the correct signals to move from G1 into S phase will enter G0 and therefore will

not undergo mitotic division unless it later receives the go-ahead signal.

Susan was examining a cell under the microscope and noticed the formation of a cell plate in the midline of the cell and the formation of nuclei at opposite poles of the cell. The cell under examination was most likely a(n)

plant cell undergoing cytokinesis.

Plant cells and animal cells differ in cytokinesis because

plant cells need to build a cell wall, while animal cells do not.

Unicellular organisms undergo mitotic division to

produce new organisms.

The drug chloral hydrate prevents elongation of microtubules by preventing the addition of new subunits to the growing end. During which stage of mitosis would chloral hydrate be most harmful?

prophase