The Cell Cycle and Mitosis

Question 1

Interphase

Answer 1

G1, S, G2, M

Question 2

G1

Answer 2

In this phase a cell grows, develops, and does normal cell things. For example, the cell is using glucose to create energy.

Question 3

S

Answer 3

In this phase the DNA inside of the cell’s nucleus is replicated. The cell will eventually divide in half. Each half will need a complete set of DNA.

Question 4

G2

Answer 4

In this phase the cell continues to grow and do it’s normal jobs. It creates a couple of proteins that it will need during the next process - cell division!

Question 5

Mitosis

Answer 5

Mitosis is a 4 step process that the cell uses to divide! The purpose of mitosis is to produce new cells for growth and repair. The cells that are produced are identical to the parent cell. Once mitosis is complete, the cell has two groups of 46 chromosomes, each enclosed with their own nuclear membrane.

Question 6

Prophase

Answer 6

First, the DNA twists into tight coils.
The membrane around the nucleus breaks apart.
Centrosomes begin to form

Question 7

Metaphase

Answer 7

The replicated chromosomes move to the middle of the cell . The pairs line up end to end across the center of the cell. (EQUATOR) Hair-like spindle fibers pull and push the chromosomes to the middle of the cell.

Question 8

Anaphase

Answer 8

The sister chromatids of each replicated chromosome begin to separate. The spindle fibers pull the centromere apart and chromatids move away from each other, toward opposite ends of the cell.

Question 9

Telophase

Answer 9

1. A new membrane forms around each set of chromosomes.
2. The chromosomes become less tightly coiled.

RESULT: Two new nuclei that are identical to each other and the original nucleus. However the cell has not divided.

Question 10

Cytokinesis

Answer 10

The cytoplasm and its components divide to form two identical cells called daughter cells.

Question 11

Somatic Cells

Answer 11

are “body” cells and contain the normal number of chromosomes ….called the “Diploid” number. Examples would be … skin cells, brain cells, etc.

Question 12

Gametes

Answer 12

are the “sex” cells and contain only ½ the normal number of chromosomes…. called the “Haploid” number Sperm cells and ova are gametes.

Question 13

Diploid

Answer 13

Diploid describes a cell that contain two copies of each chromosome. Nearly all the cells in the human body carry two homologous, or similar, copies of each chromosome. The only exception is cells in the germ line, which go on to produce gametes, or egg and sperm cells. All body cells.

Question 14

After Interphase

Answer 14

Chromosomes are doubled. At the end of interphase comes the mitotic phase, which is made up of mitosis and cytokinesis and leads to the formation of two daughter cells. Mitosis precedes cytokinesis, though the two processes typically overlap somewhat.

Question 15

Mitosis

Answer 15

One DIPLOID cell divides ONE time to create
TWO CLONE cells that are DIPLOID
Cell division = PMAT - one time Produces

Question 16

Haploid

Answer 16

Half the chromosomes. Haploid is the quality of a cell or organism having a single set of chromosomes

Question 17

X

Answer 17

X chromosomes are female sex chromosomes.

Question 18

X and Y

Answer 18

X and Y are male sex chromosomes

Question 19

How many chromosomes do humans have?

Answer 19

46

Question 20

Meiosis

Answer 20

One DIPLOID cell divides TWO times to create
FOUR genetically unique cells that are HAPLOID
Cell division = PMAT - happens twice!
By the end of meiosis, the resulting reproductive cells, or gametes, each have 23 genetically unique chromosomes. The overall process of meiosis produces four daughter cells from one single parent cell. Each daughter cell is haploid, because it has half the number of chromosomes as the original parent cell. Meiosis is Haploid.

Question 21

Why? Mitosis

Answer 21

1. To REPLACE damaged or worn out cells.
2. So multicellular organisms can GROW.
3. For asexual REPRODUCTION.
4. So that cells don’t get too BIG.

Question 22

Why? Meiosis.

Answer 22

1. For sexual REPRODUCTION.
2. To CREATE gametes (sex cells).
3. So that GAMETES will have half of the number of chromosomes.

4.  Because.... MATH!  
Sperm cell (23) + Egg cell (23) = zygote (46)

Question 23

The stages of meiosis.

Answer 23

Meiosis is used only for the production of sperm and eggs.
It consists of two successive cell divisions, producing four daughter cells
Meiosis has two main functions: to reduce the chromosome number in the gamete to 23, and to ensure that every gamete is genetically unique.

Question 24

Meiosis Results

Answer 24

Four haploid sex cells have been formed from one original diploid cell.

Haploid cells are gametes, transmitting the genes they contain to offspring.