Cell Cycle Test Review

By what process do bacteria reproduce?

binary fission. In this process the bacterium, which is a single cell, divides into two identical daughter cells. Binary fission begins when the DNA of the bacterium divides into two (replicates)

What is uncontrolled cell division?

cancer

What is division of the cytoplasm called?

cytokinesis

How do you calculate surface area to volume ratio?

divide the surface area by the volume (sa=, v=lxwxh)

What are chromosomes?

long DNA molecule with part or all of the genetic material of an organism.

What is the reason for mitosis?

process where a single cell divides into two identical daughter cells (cell division)

What happens to the chromosome number as a cell proceeds through the cell cycle?

the DNA content per chromosome doubles during S phase (each chromosome starts as one chromatid, then becomes a pair of identical sister chromatids during S phase), but the chromosome number stays the same. A chromatid, then, is a single chromosomal DNA molecule.

What is the product of mitosis?

two identical daughter cells, genetically identical to the original cell, all having 2N chromosomes.

What are the phases of mitosis? Put them in order that they occur.

Prophase, metaphase, anaphase, and telophase

Describe in detail what happens in each phase. Pay particular attention to what happens to the chromosomes

Prophase: the parent cell chromosomes which were duplicated during S phase condense and become thousands of times more compact than they were during interphase. Cohesin forms rings that hold the sister chromatids together, whereas condensin forms ring that coil the chromosomes into highly compact forms. Metaphase: stage in the cell cycle where all the genetic material is condensing into chromosomes. ... During this stage, the nucleus disappears and the chromosomes appear in the cytoplasm of the cell. Anaphase: the sister chromatids separate from each other and are pulled towards opposite ends of the cell. The protein "glue" that holds the sister chromatids together is broken down, allowing them to separate. Each is now its own chromosome. The chromosomes of each pair are pulled towards opposite ends of the cell. Telophase: the chromosomes arrive at the cell poles, the mitotic spindle disassembles, and the vesicles that contain fragments of the original nuclear membrane assemble around the two sets of chromosomes. ... This dephosphorylation results in the formation of a new nuclear membrane around each group of chromosomes.

What are the phases of the cell cycle? Describe in detail what happens in each phase. Add a diagram to indicate the order in which they occur.

Interphase (the cell grows and the nuclear DNA is duplicated), mitosis (nuclear division that results in the formation of two genetically identical daughter cells.), cytokinesis (division of the cytoplasm)

Which phase is the longest? Which phase is the shortest?

Interphase is the longest and cytokinesis is the shortest

Why are stem cells important to medicine?

Stem cells represent an exciting area in medicine because of their potential to regenerate and repair damaged tissue. Some current therapies, such as bone marrow transplantation, already make use of stem cells and their potential for regeneration of damaged tissues.

What controls cell division? What are the molecules? What type of molecules are they?

The central components of the cell-cycle control system are cyclin-dependent protein kinases (Cdks), whose activity depends on association with regulatory subunits called cyclins. Oscillations in the activities of various cyclin-Cdk complexes leads to the initiation of various cell-cycle events.

Why is having a large surface area to volume ratio important? Name at least three reasons.

The important point is that the surface area to the volume ratio gets smaller as the cell gets larger. Thus, if the cell grows beyond a certain limit, not enough material will be able to cross the membrane fast enough to accommodate the increased cellular volume, if one cell dies it won't make a huge difference

What are adult stem cells?

Adult stem cells are undifferentiated cells, found throughout the body after development, that multiply by cell division to replenish dying cells and regenerate damaged tissues.

How are cancerous cells different from normal cells?

An abnormal mass of tissue that forms when cells grow and divide more than they should or do not die when they should.

What is a tumor?

An abnormal mass of tissue that forms when cells grow and divide more than they should or do not die when they should. Tumors may be benign (not cancer) or malignant (cancer). Benign tumors may grow large but do not spread into, or invade, nearby tissues or other parts of the body.

Compare the process in plants and animals.

Animals usually move around and find their own food, while plants are usually immobile and create their food via photosynthesis. Plants and animals both have cells that contain DNA, yet the structure of their cells differs.

When a cell grows what happens to the cell's surface area compared to the volume?

As a cell grows bigger, its internal volume enlarges and the cell membrane expands. Unfortunately, the volume increases more rapidly than does the surface area, and so the relative amount of surface area available to pass materials to a unit volume of the cell steadily decreases.

Define cell differentiation

Cellular differentiation is the process in which a cell changes from one cell type to another. Usually, the cell changes to a more specialized type.

What are the cells called produced from mitosis?

Daughter cells

Compare adult stem cells to embryonic stem cells.

Embryonic stem cells are derived during early development at the blastocyst stage and are pluripotent, meaning that they can differentiate into any cell type. ... In contrast, adult stem cells are rare, undifferentiated cells present in many adult tissues.

What are embryonic stem cells and why are they special?

Embryonic stem cells can, in theory, produce any type of tissue in large quantities. Researchers use these cells to study development and disease and, hopefully, to find treatments. Within 6 months, the two or three dozen cells taken from a single embryo can generate millions of embryonic stem cells