Biology Chapter 10: How Cells Divide

What are the three checkpoints at which the cell cycle can be delayed, or even halted, depending on the cell's internal state and any external signals it may have received?

- Metaphase checkpoint - G1/SG1/S checkpoint - G2/MG2/M checkpoint

Bacterial cells divide to produce new cells for which of the following?

- Reproduction - Population growth

Two irreversible points in the cell cycle are replication of ____ material and ____ of sister chromatids.

1. Generic 2. Separation

In a diploid eukaryotic cell, a pair of chromosomes, one maternal and the other paternal, are known as being ____ chromosomes. Each chromosome in a pair is termed a(n) ____.

1. Homologous 2. Homologue

During metaphase, kinetochore microtubules move chromosomes to the middle of the cell where they are lined up on the ____ ____.

1. Metaphase 2. Plate

During the five phases of ____, the replicated genetic material is partitioned into ____ new nuclei.

1. Mitosis 2. Two (2)

The two main classes of cancer causing genes are ____ and ____-____ genes.

1. Oncogene 2. Tumor 3. Suppressor

Cytokinesis in plant cells involves the formation of a cell ____ which starts at a right angle to the spindle apparatus in the interior of the cell and extends out to the plasma ____.

1. Plate 2. Membrane

After DNA replication each condensed chromosome is made of two identical halves called ____ ____.

1. Sister 2. Chromatids

The chromosome number in the body cells of most eukaryotic species falls within which range?

10 and 50

Typically, a dividing mammalian cell completes its cell cycle in about how many hours?

24 hours

In a typical, mature, dividing mammalian cell, what proportion of the cell cycles is taken by mitosis?

A very small fraction (about 5%)

The cleavage furrow of animal cells is formed with the help of a constricting belt made of the protein ____.

Actin

At the beginning of which phase do the centromeres of sister chromatids split apart allowing sister chromatids to separate from each other?

Anaphase

During the ____ of mitosis, the centromeres of sister chromatids split apart allowing sister chromatids to move away from each other.

Anaphase

The shortest stage of mitosis is ____.

Anaphase

Which of the following is the shortest stage of mitosis?

Anaphase

How do bacteria reproduce?

Binary fission

One complete set of chromosomes necessary to define an organism is also known as the ____ number of chromosomes.

Haploid

Cell division in both bacterial and eukaryotic cells produces genetically ____ cells.

Identical

Which statement accurately compares cell division in bacterial and eukaryotic cells?

In both types of cells, cell division produces two new cells with the same genetic information as the original cell.

Cytokinesis in animal cells involves the formation of a ____ furrow around the cell.

Cleavage

When DNA replicates, the sister chromatids are held together at their centromeres by which of the following complex of proteins?

Cohesins

Some animal cells, such as muscle and nerve cells, remain permanently in which of the following phases of the cell cycle?

G0 phase

Condensation of chromosomes is initiated in the ____ phase of interphase and continues until the end of prophase.

G2

During ____, which includes the G1, S and G2 phases of the cell cycle, the cell grows and chromosomes replicate in preparation for cell division.

Interphase

In actively dividing cells, the G1, S, and G2 phases are collectively known as which of the following?

Interphase

In an actively dividing eukaryotic cell, the G1, S, and G2 phases collectively constitute the ____.

Interphase

While preparing to divide, the cell grows and copies its chromosomes during which stage?

Interphase

Which of the following describes the number of chromosomes in eukaryotic cells?

It varies considerably between different species.

During metaphase, the microtubules attached to the centromere region of the condensed chromosomes are which of the following types of microtubules?

Kinetochore

During prometaphase, which protein complex on each sister chromatid attaches to the spindle?

Kinetochore

During prometaphase, sister chromatids attach to the spindle by their ____, which are attached to the centromere region of each sister chromatid.

Kinetochores

During ____ the chromosomes are aligned midway between the spindle poles.

Metaphase

The pairs of sister chromatids align themselves in a single row along a plane half-way between the poles during which phase of mitosis?

Metaphase

During telophase, the nuclear envelope re-forms to produce two separate ____.

Nuclei

During cell division, chromatin becomes increasingly more condensed with one of the highest states of condensation seen in X-shaped metaphase chromosomes. In these structures, DNA is organized ____.

On a protein scaffold

What type of genes were discovered in viruses and can cause a malignant transformation when introduced into a cell?

Oncogenes

In a homologous pair of chromosomes, what is the origin of each chromosome?

One is paternal and one is maternal.

What phase of mitosis is characterized by the reformation of the nuclear envelope and the production of two separate nuclei?

Telophase

Which is the final phase of mitosis?

Telophase

____ is the final phase of mitosis.

Telophase

Which statement accurately compares chromatin condensation in dividing and nondividing cells?

The chromatin of a cell undergoing division is more condensed than the chromatin of a nondividing cell.

Chromatin is a complex with ~40% DNA and ____.

~60% Protein

In the body of an animal, some cells remain in the ____ phase permanently, while others can proceed to the G1G1 phase when new cells are needed (e.g., during an injury).

G0

____ is a term to describe cells growing out of control.

Cancer

The ____ enzymes control progression through the checkpoints in the cell cycle.

Cdk

What enzymes control the progression of cells through the cell cycle checkpoints?

Cdks

What is a sequence of growth, replication, and division that produces new eukaryotic cells called?

Cell cycle

If necessary (e.g., if DNA is damaged), the cell cycle can be arrested at specific points called ____.

Checkpoints

In multicellular eukaryotic organisms, the production of new cells follows a highly regulated sequence of growth, DNA replication, and division. This sequence is referred to as the cell ____, which consists of the G1, S, G2, and M phases.

Cycle

After completing mitosis, cells divide into two daughter cells. This phase of the cell cycle is called ____.

Cytokinesis

____ is the phase of the cell cycle when the cell divides into two equal halves.

Cytokinesis

The cells of many eukaryotic organisms contain two sets of chromosomes and are said to contain a ____ number of chromosomes.

Diploid

Cytokinesis in ____ cells does not involve a cleavage furrow, but rather a cell plate.

Plant

Which of the following produce a cell plate during cytokinesis?

Plant cells

Condensation of chromosomes continues throughout which phase of mitosis?

Prophase

Which is the first stage of mitosis?

Prophase

Chromosomes are composed of chromatin which is a complex of DNA and which of the following?

Protein

Cells control the cell cycle by integrating internal information and external signals and delaying (or even halting) the cell cycle at ____ (number) checkpoints.

Three (3)

A ____ is a cluster of cancerous cells that have lost control of their growing.

Tumor