The Cell Cycle, Cell Growth And Differentiation

Question 1

Name the 4 phases of the cell cycle…

Answer 1

M- (mitosis) is usually followed by cytokinesis.
G1
S- period during which DNA replication occurs.
G2
The cell grows throughout interphase, which includes G1, S, and G2. The relative lengths of the cell cycle phases shown here are typical of rapidly replicating mammalian cells.

Question 2

What’s the difference between mitosis and cytokinesis?

Answer 2

Mitosis and cytokinesis differ in that mitosis the process in which a duplicated genome within a cell separates into identical halves, while cytokinesis involves the division of cellular cytoplasm into two daughter cells.

Question 3

Define genetic predisposition

Answer 3

an increased likelihood of developing a particular disease based on a person’s genetic makeup.
A genetic predisposition results from specific genetic variations that are often inherited from a parent

Question 4

Define mutagen and give 3 examples

Answer 4

an agent, such as radiation or a chemical substance, which causes genetic mutation.
Eg. Bromine, benzene, X Ray’s

Question 5

Define differentiation

Answer 5

The normal process by which a less specialized cell develops or matures to possess a more distinct form and function.

Question 6

Describe 3 types of stem cells

Answer 6

Embryonic- derived from embryos
Adult- found in adult humans
Pluripotent- “master” stem cells. Can make any tissue

Question 7

Difference between embryo and foetus…

Answer 7

“The embryo is defined as the developing pregnancy from the time of fertilization until the end of the eighth week of gestation, when it becomes known as a fetus,”

Question 8

Name 3 sources of stem cells

Answer 8

Cord blood, umbilical cord blood.
Bone marrow.
Skin.
Teeth

Question 9

Differences between embryonic and adult stem cells

Answer 9

Embryonic stem cells can become all cell types of the body because they are pluripotent.
Adult stem cells are thought to be limited to differentiating into different cell types of their tissue of origin.

Question 10

List 3 reasons why cells in an adult human need to be continually replaced?

Answer 10

1. Repairing damaged tissues.
2. Cells have a life span. For example, RBC live only for 120 days and new RBC replace them to continue with proper functioning of the body.
3. It helps in growth and reproduction.