Cell Division and Inheritance

Question 1

What is cancer

Answer 1

The uncontrolled growth and division of cells
Normal cells of the body spend most of their time in interphase
Cancer results from the G1 phase of the cell cycle being affected, the cells are much smaller than normal, the time necessary for the cell cycle shortens

Question 2

How are cancer cells different from regular cells?

Answer 2

They spend less time in interphase
They have uncontrolled mitosis –
They grow faster than normal cells
They can break away from groups of cells and travel to other places in the body.
They have a different physical structure – often with parts that allow them to grip
and grab onto other cells and tissues

Question 3

One way that cancer cells are physically different from normal cells

Answer 3

gripping structures

Question 4

How do you end up dying of cancer?

Answer 4

Mutated cells keep reproducing at a high rate, causing the body to put lots of energy into their production and upkeep. All of this energy being devoted to these cancer cells causes other normal cells to suffer and can ultimately lead to death.

Question 5

Different possible causes of cancer

Answer 5

Chemicals, UV radiation, virus such as the HPV virus, x-rays, and genetics
All of these items increase the likelihood of cells becoming mutated which means that cells may not repair and follow a proper cell division cycle

Question 6

what is a tumor?

Answer 6

Cluster of cells going through uncontrolled mitosis.

Question 7

types of tumors

Answer 7

Benign Tumors – these tumors have cells that do NOT migrate to other parts of the body and do not harm other parts of the body
Malignant Tumors – these tumors have cells that can migrate to other parts of the body, potentially causing the cancer cells to spread in the body

Question 8

What happens if the body is going through metastasis?

Answer 8

When a tumor or cancer cells have spread from their original source, this is called metastasis.

Question 9

what is a biopsy?

Answer 9

In a biopsy, the doctor removes a sample of the cells from the tumor to analyze under a microscope to determine whether the cells are cancerous

Question 10

Cancer treatments

Answer 10

surgery - removing the tumor
chemotherapy - To kill cancer cells in the body, doctors can inject powerful drugs into the body. This is usually done as an injection of drugs into the blood. These drugs kill cells quickly and aggressively. These drugs will also kill many normal cells in the body.
radiation - directing radiation at the tumor, radiation willl kill the cells in the tumor, hopefully causing it to shrink and die

Question 11

phases of the cell cycle

Answer 11

G1,S,G2, M
M includes mitosis and cytokinesis
interphase is everything else

Question 12

Interphase parts

Answer 12

G1
Cell growth
Cells increase in size and synthesize new proteins and organelles
S
DNA replication
New DNA is synthesized when the chromosomes are replicated
Cell at the end of the S phase contains twice as much DNA as it did at the beginning
G2
Preparing for cell division
Many of the organelles and molecules required for cells division are produced

Question 13

phases of cell division

Answer 13

Prophase
Metaphase
Anaphase
Telophase
cytokinesis

Question 14

prophase

Answer 14

Nuclear envelope breaks down
Chromatin condenses into chromosomes
spindle fibers attach
centrosomes moves to opposite poles

Question 15

Metaphase

Answer 15

Chromosomes line up in the center of the cell, spindle fibers fully form, nucleus is gone

Question 16

Anaphase

Answer 16

sister chromatids are split, pulled apart by spindle fibers, move to opposite sides of cell

Question 17

Telophase

Answer 17

Nucleus reforms
chromosomes unwind and turns back into chromatin
cytokinesis begins

Question 18

cytokinesis

Answer 18

cytoplasm splits, fully making parent cell into two new cells

Question 19

If sister chromatids did not like up correctly during metaphase

Answer 19

DNA would not be split correctly , so neither of the cells would have the correct amount of DNA. Might be hard for spindle fibers to connect, might draw entire chromosome to one side, would cause an imbalance in the DNA

Question 19

G0

Answer 19

Cells spend much more time in interphase than in cell division (mitosis and cytokinesis)
Occasionally cells stop dividing and enter another phase, G0
Not dividing cells are staying in G0 long term and will not do any more mitosis
Sometimes cells are in G0 only for a little bit and do not stay there permanently
Cells split of into G0 coming off from G1, cell has maybe grown a little bit, but not fully grown, hasn’t really begun dividing yet

Question 20

what happens to mutated cells

Answer 20

Apoptosis - Cell cycle has a regular system of checks and balances that prevents damaged or mutated cells from proceeding to the next phase. One way an organism deals with the problems is to kill the damaged cell before it passes on the problem to its daughter cells.

Sometimes instead of being killed, damaged or mutated cells in an organism enter G0, which stops them from copying and making other damaged cells, but also gives the body an opportunity to potentially fix the damage

Question 21

mitosis in plant vs. animals cells

Answer 21

Cytokinesis
In animal cells, cytokinesis occurs by a process known as cleavage, forming a cleavage furrow, a shallow groove in the cell surface. Cell membrane is drawn inward until the cytoplasm is pinched into two nearly equal parts
In plant cells, a cell plate forms during cytokinesis, which gradually develops into cell membranes that separate the two daughter cells, a cell wall then forms in between the two new membranes

plant cells also don’t have centrioles