Cell Division

Question 1

List the four steps of cell division.

Answer 1

G1, Synthesis, G2, Mitosis.

Question 2

What steps are part of the interphase?

Answer 2

G1, Synthesis, and G2.

Question 3

Explain what happens during each phase.

Answer 3

In G1- The cell begins to grow
S phase- DNA is replicated
In G2- The cell grows even more and completely develops. Prepares for cell division.
Mitosis- The cell is divided into two daughter cells.

Question 4

What are some reasons why cells divide?

Answer 4

The Cell is getting too big
Growth and Development
Healing and repair
Cell reproduction

Question 5

What are the different types of cell reproduction?

Answer 5

Sexually: Offspring is a combination of two parents.
Asexually: Offspring is identical to its single parent.

Question 6

What is interphase?

Answer 6

Interphase is the stage of growth and preparation. Chromosomes are copied (# doubles) and appear as threadlike unorganized coils, called chromatin, at first.
Each chromosome changes to sister chromatids by the end of this phase.

Question 7

What is a chromosome?

Answer 7

A thread-like structure in the nucleus of most living cells carries genetic information in the form of genes.

Question 8

What is a chromatid?

Answer 8

Two thread-like strands into which a chromosome divides longitudinally during cell division. Each contains a double-helix of DNA.

Question 9

What is chromatin?

Answer 9

The material of which the chromosomes of organisms other than bacteria are composed, consisting of proteins, RNA and DNA

Question 10

What do different checkpoints check for?

Answer 10

G1: The cell needs to have grown big enough.
G2: There can be no errors in DNA replication.
Middle of Mitosis: DNA needs to be lined up evenly.

Question 11

What is cancer?

Answer 11

Cancer is uncontrolled cell growth. They form in tumors of masses of abnormal cells.

Question 12

What is a benign tumor?

Answer 12

Lump remains at the original site

Question 13

What is a Malignant tumor?

Answer 13

Malignant tumors invade surrounding tissues and transport cancer cells to other parts of the body, where they may form other tumors.

Question 14

What parts of the Cell Cycle is interphase?

Answer 14

Interphase is not part of mitosis-it is the time between cell division. Interphase includes G1, S, and G2.
During interphase, the cell is doing its normal metabolic activities like protein synthesis. The DNA duplicates to get ready for mitosis (M phase).

Question 15

What are the three steps of prophase?

Answer 15

1. Mitosis begins. Chromatin is condensed into chromosomes.
2. Centrioles form spindle fibers and begin to move to opposite ends of the cell.
3. Nuclear membrane breaks down and disappears.

Question 16

What are the two steps of Metaphase?

Answer 16

1. Chromosomes attach to the spindle fibers and line up at the equator (middle) of the cell, the metaphase plate.
2. Spindle assembly checkpoint: perfect chromosome separation can be guaranteed.

Question 17

What are the two steps of anaphase?

Answer 17

1. The sister chromatids separate at the centromeres.

2. Each chromatid heads to opposite poles of the cell.

Question 18

What are the three steps of telophase?

Answer 18

1. New nuclear membranes start to form around the DNA.
2. The chromosomes begin to decondense back to chromatin.
3. Cytoplasm begins to pinch in animal cells forming a cleavage furrow and a cell wall begins to form in plant cells- this is cytokinesis.