Unit 3.2 cell reproduction Growth and Development Study Guide

The level of cyclins in a cell increases during the M phase of the cell cycle. What might happen to a cell if no cyclins were present during the M phase?

A cell that lacked cyclins would probably not undergo mitotic division, and then it would continue to grow, have DNA overload, and exchange materials inefficiently until it dies.

What effect does cell size have on a cell's ability to efficiently carry out its activities?

A large cell carries out its activities less efficiently than a small one does.

Normal cells grown in a petri dish tend to divide until they form a thin layer covering the bottom of the dish. How would you expect cancer cells to behave in this situation?

Cancer cells are not constrained by crowding and would probably continue to grow after forming a thin layer covering the bottom of the petri dish.

How do cancer cells differ from normal cells?

Cancer cells do not respond to the signals that control the growth of normal cells. As a result, cancer cells form tumors and can spread throughout the body.

Which of the following happens when a cell divides?

Each daughter cell receives its own copy of the parent cell's DNA.

Stem cells taken from embryos are totipotent.

False

Cancer is a disorder in which some of the body's cells lose the ability to control growth and division.

True

The structure labeled A in Figure 10-8 is called the

cell plate

In eukaryotic cells, the timing of the cell cycle is regulated by

cyclins.

The larger a cell becomes, the BLANKS efficiently it is able to function.

less

During which phase of mitosis do the chromosomes line up along the middle of the dividing cell?

metaphase

What phase of mitosis is labeled 5 in Figure 10-9 above?

metaphase

The two main stages of cell division are called

mitosis and cytokinesis.

Compared to small cells, large cells have more trouble

moving needed materials in and waste products out.

Cancer affects

multicellular organisms only.

When during the cell cycle are chromosomes visible?

only during cell division

What phase of mitosis is labeled 2 in Figure 10-9 above?

prophase

An advantage of sexual reproduction over asexual reproduction is that sexual reproduction

provides genetic diversity

Cancer cells form masses of cells called

tumors.

As a cell becomes larger, its

volume increases faster than its surface area.

The rate at which wastes are produced by a cell partially depends on the cell's

volume.

1. Surface area 2.Volume 3.Surface Area-to-Volume Ratio

1. The amount of "covering" of the object. 2. The amount of space inside the object; the amount of space the object takes up. 3. The amount of surface area per unit volume of an object or collection of objects.

What order do the phases of mitosis occur in?

1. prophase 2.Metaphase 3.anaphase 4.telophase 5. interphase or G2 phase

During BLANK reproduction, cells can produce genetically different offspring, whereas, during BLANK reproduction, cells produce genetically identical offspring.

1. sexual 2. asexual

1. Cancer 2. Metastasis 3. Benign 4. Malignant 5. Tumor

1.Cells grow and divide uncontrollably. 2.The formation of secondary tumors. 3.Noncancerous, tumor does not spread to surrounding healthy tissue. 4.Cancerous, tumor invades and destroys surrounding healthy tissue. 5.Mass formed by cancerous cells.

1. Interphase 2.G1 Phase 3.S Phase 4.G2 Phase 5.M phase 6. Cytokinesis

1.Period of the cell cycle between cell divisions. G1 Phase, S Phase and G2 Phase occur during this part of the cell cycle. 2.Cells do most of their growing. It begins when mitosis is complete and ends when DNA replication begins. 3.DNA is synthesized as chromosomes are replicated. 4.Many of the molecules and cell structures required for cell division are produced; usually this is the shortest phase of the cell cycle. 5.Usually much shorter than interphase. Results in two daughter cells. Mitosis and Cytokinesis occur during this phase. 6.The cytoplasm divides and two cells are formed. The final step in cell division. This step usually takes place during telophase.

1.Differentiation 2.Stem Cells 3.Embryonic Stem Cells 4.Adult Stem Cells 5.Totipotent 6.Pluripotent 7.Multipotent

1.Process by which cells become specialized in structure and function. 2.Unspecialized cells from which differentiated cells develop. 3.Cells in the inner cell mass are embryo. Totipotent. 4.Cells mainly found in bone marrow, hair follicles, but there are also some in brain, heart, and skeletal muscle. Multipotent. 5.Cells that can develop into any type of cell in the body (including the cells that make up the extraembryonic membranes and placenta). 6.Cells that are capable of developing into most, but not all, of the body's cell types. 7.Cells with limited potential to develop into many different types of differentiated cells

1. Cyclins 2. internal Regulators 3. External Regulators 4. Growth Factors 5. Apoptosis

1.Proteins that regulate the cell cycle. 2.Respond to events inside the cell and let cell cycle proceed only when certain steps have already happened. 3.Respond to events outside the cell and direct cells to speed up or slow down the cell cycle. 4.Stimulate the growth and division of cells and are important for wound healing and embryonic development. 5.A process of programmed cell death.

1. Mitosis 2. Prophase 3. Metaphase 4. Anaphase 5. Telophase

1.The cell's nucleus divides. Can be divided into four phases (prophase, metaphase, anaphase and telophase) that lead up to cytokinesis. 2.Chromatin condenses into chromosomes. The centrioles separate, the spindle begins to form, and the nuclear envelope breaks down. 3.The chromosomes line up across the center of the cell. 4.Sister chromatids separate and move along the spindle fibers toward opposite ends of the cell. 5.The chromosomes gather at opposite ends of the cell and lose their distinct shapes. Two new nuclear envelopes form.

1. Chromosome 2.Chromatid 3.Chromatin 4.DNA 5.Histone 6.Nucleosome 7.Centromere

1.Threadlike structure of DNA and protein that contains the genetic information. Found in nucleus of eukaryotes and cytoplasm of prokaryotes. 2.One of two identical "sister" parts of a duplicated chromosome. 3.Substance found in eukaryotic chromosomes that consists of DNA tightly coiled around histones. 4.Deoxyribonucleic acid, genetic material that organisms inherit from their parents. 5.Highly basic proteins abundant in lysine and arginine residues that are found in eukaryotic cell nuclei that act as spools around which DNA winds to create structural units called nucleosomes. 6.Consists of a segment of DNA wound around eight histone proteins and resembles thread wrapped around a spool; the fundamental subunit of chromatin. 7.Region of a chromosome where the two sister chromatids attach.

A cell that has 5 chromosomes in the G1 phase will have BLANK chromatids in the G2 phase.

10

If the surface area of a cell that is shaped like a cube increases 100 times, its volume increases about

1000 times.

The number of sister chromatids in a human body cell that is entering cell division is

92

Which of the following are two problems that growth causes for cells?

As a cell grows larger, more demands are placed on its DNA, and the cell has more trouble moving enough nutrients and wastes across the cell membrane.

Which type of reproduction, sexual or asexual, is best suited for organisms that live in a place where environmental conditions are stable?

Because the offspring of asexual reproduction are genetically identical to parents, they have the characteristics that help them survive in the conditions in which the parent cells survived. They might not have characteristics to survive should the conditions change.

How are embryonic stem cells different from adult stem cells?

Embryonic stem cells come from embryos and are pluripotent, whereas adult stem cells come from adults and are only multipotent.

In eukaryotes, the spindle breaks down during prophase and re-forms during telophase.

False

Mitosis is a form of sexual reproduction, because the daughter cells that form are identical to the parent cell.

False

Most of a cell's growth takes place during the G2 phase of the cell cycle.

False

People opposed to stem cell research argue that it is unethical to collect embryonic stem cells because it usually preserves an embryo.

False

The smaller a cell is, the more difficult it is for the cell to move enough nutrients and wastes across its cell membrane to maintain its normal functions.

False

Typically, the longest phase of mitosis is metaphase.

False

Look at Figure 10-8. Once structure A has completely formed, another phase of the cell cycle will start. This phase will be called

G1

The main events of the cell cycle are labeled A, B, C, and D in Figure 10-3. What is the name of the event labeled A and what happens during this event?

G1 phase, cell growth

The main events of the cell cycle are labeled A, B, C, and D in Figure 10-3. What is the name of the event labeled C and what happens during this event?

G2 phase, preparation for mitosis

Which pair includes a phase of the cell cycle and a cellular process that occurs during that phase?

G2 phase, preparation for mitosis

Why is harvesting adult stem cells less controversial than harvesting embryonic stem cells?

Harvesting adult stem cells do not generally harm the donor, whereas harvesting embryonic stem cells usually destroys the embryo.

How are metaphase and anaphase different?

In metaphase the sister chromatids are still attached to one another and are found in the middle of the cell, whereas in anaphase the sister chromatids have separated and are beginning to move to opposite sides of the cell.

What is the the difference between cytokinesis in plant cells and animal cells?

In plant cells, a cell plate forms in the cytoplasm midway between each new nucleus. The cell plate gradually develops into a separating membrane, and a cell wall begins to appear in the cell plate. In animal cells, there is no cell plate. The cell membrane is drawn inward until the cytoplasm is pinched into two nearly equal parts.

Which of the following is a correct statement about the events of the cell cycle?

Interphase consists of the G1, S, and G2 phases.

During which phase in the cell cycle does mitosis happen?

M phase

The main events of the cell cycle are labeled A, B, C, and D in Figure 10-3. What is the name of the event labeled D and what happens during this event?

M phase, cell division (mitosis and cytokinesis).

Why are stem cells important?

They have the potential to develop into other cell types.

What is the role of the spindle fibers during mitosis?

They help separate the chromosomes.

A single-celled organism would not be expected to undergo cell differentiation.

True

An imaginary cubic cell with a side length of 10 mm would have a ratio of surface area to volume of 6 : 10.

True

During cytokinesis, a cell undergoing cell division finally splits into two daughter cells.

True

One difference between cyclins and growth factors is that each cell produces its own cyclins, but growth factors are signals that can be sent from one cell to another.

True

The cell shown in step E in Figure 10-7 above is undergoing telophase.

True

The structure shown in Figure 10-5 is a replicated chromosome.

True

As a cell's size increases, its ratio of surface area to volume increases.

True.

One difference between cell division in plant cells and in animal cells is that plant cells have

a cell plate.

After cell division, each daughter cell has

a higher surface area/volume ratio than the parent cell.

Harvesting BLANK stem cells from a willing donor is not as controversial as harvesting techniques that involve the destruction of an embryo.

adult

The phase of mitosis shown in step D in the Figure 10-7 above is called

anaphase

What phase of mitosis is labeled 1 in Figure 10-9 above?

anaphase

During normal development, the cells between toes and fingers die by BLANK, a process of programmed cell death.

apoptosis

Prokaryotes reproduce by an asexual process known as

binary fission

During normal mitotic cell division, a parent cell that has four chromosomes will produce two daughter cells, each containing

four chromosomes.

Which of the following are external regulators of the cell cycle? check

growth factors

Cancer is a disorder in which some cells have lost the ability to control their

growth rate.

What phase of mitosis is labeled 3 in Figure 10-9 above?

interphase or G2 phase

Cell division occurs in two main stages, the first of which is called

mitosis

The process shown in Figure 10-8 occurs only in BLANK cells that are going through cytokinesis.

plant

Which of the following is a phase of mitosis?

prophase

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

prophase, metaphase, anaphase, telophase

During which phase(s) of mitosis are structures like the one shown in Figure 10-5 visible?

prophase, metaphase, and anaphase

The first phase of mitosis is called

prophase.

Cyclins are a family of closely related proteins that

regulate the cell cycle.

Which of the following is a possible future benefit of stem cell research?

reversing damage from a heart attack

The structures labeled B in Figure 10-5 are called

sister chromatids.

A cell with a defective p53 gene is likely to check

stop responding to growth regulators.

What phase of mitosis is labeled 4 in Figure 10-9 above?

telophase

Which event occurs during interphase?

Centrioles duplicate.

What is the difference between chromatids and chromatin?

Chromatids are two identical DNA strands joined by a centromere, and chromatin is the material (DNA and proteins) that makes up chromosomes.

A multicellular organism begins life as a single cell—a fertilized egg with a complete set of chromosomes. The picture in Figure 10-2 above shows how the cell divides to become two cells, then four cells, eight cells, and so on. Which of the following statements best describes what happens during this process?

Chromosomes are duplicated before cell division so that each new daughter cell has a complete set.

Which of the following explains why normal cells grown in a petri dish tend to stop growing once they have covered the bottom of the dish?

Contact with other cells stops cell growth.

Cell division is represented in Figure 10-3 by the letter:

D

What is differentiation?

Differentiation is the process by which cells become specialized.

Which advantage of having the a cell's DNA bundled into separate chromosomes is illustrated in Figure 10-1 above?

During cell division, each daughter cell will get the same number of genes.

Some cells form a cell plate during cytokinesis. Which of the following is true of the cells in Figure 10-6 above?

Only cell B forms a cell plate during cytokinesis.

How does packaging genetic information into chromosomes help the process of cell division?

Packaging genetic material into chromosomes helps the cell separate the DNA precisely during cell division. If the genetic material was spread out into smaller pieces, some of the material might get lost more easily when the cell divided into two cells.

When during the cell cycle is a cell's DNA replicated?

S phase

The main events of the cell cycle are labeled A, B, C, and D in Figure 10-3. What is the name of the event labeled B and what happens during this event?

S phase, DNA replication

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 controls on cell growth and division can be turned on and off.

The process by which a cell divides into two daughter cells is called

cell division.

The structure labeled A in Figure 10-5 is called the

centromere.

A doctor might treat a patient with cancer by giving the patient BLANK, which are drugs that can kill cells that are rapidly dividing.

chemotherapy

In Figure 10-4, what role does structure A play in mitosis?

connect to spindle fibers

When cells are grown in a laboratory, which of the following is a factor that can stop normal cells from dividing?

contact with other cells

Adult skin cells can no longer become other types of cells because they have already undergone

differentiation

Stem cells are unique because they have not yet completed the process of BLANK and become a distinct type of cell.

differentiation

During early development, all cells in the embryo of a multicellular organism are identical. Later on in development, the cells will become specialized through a process called

differentiation.

Which of the following lists structures from smallest to largest?

double helix, nucleosome, coil, supercoil, chromosome

All of the following are problems that growth causes for cells EXCEPT

excess oxygen.