Cell Division

Question 1

What are 4 reasons cells divide?

Answer 1

growth, reproduction, renewal/replacement, to keep the surface area to volume ratio big

Question 2

What happens if a cell gets too big?

Answer 2

The demands of the cell (materials and energy needed) cannot be met. The cell membrane cannot diffuse the amount of material that is needed by the bigger cell.

Question 3

What are some characteristics of asexual reproduction?

Answer 3

only one parent, genetic info is the same from parent to offspring, no fertilization of egg and sperm

Question 4

What are some characteristics of sexual reproduction?

Answer 4

two parents, fertilization of egg by sperm, genetic information of new cell is different than parent

Question 5

What is meiosis?

Answer 5

the formation of sex cells (sperm and eggs- 23 chromosomes)

Question 6

What is mitosis?

Answer 6

the formation of body cells (46 chromosomes)

Question 7

What is chromatin?

Answer 7

DNA wrapped around proteins called histones, (DNA in an unwound state)

Question 8

What is a chromosome?

Answer 8

Chromatin tightly wound up

Question 9

When is DNA in the chromatin state?

Answer 9

During Interphase (preparation for division)

Question 10

When is DNA in the chromosome state?

Answer 10

During Mitosis ( prophase, metaphase, anaphase, telophase)

Question 11

How many chromosomes do humans have?

Answer 11

23 pairs or 46 total

Question 12

Which sex chromosomes do you have if you are female?

Answer 12

XX

Question 13

Which sex chromosomes do you have if you are male?

Answer 13

XY

Question 14

What is a karyotype?

Answer 14

an organized picture of someones chromosomes

Question 15

Why is DNA replication so important?

Answer 15

it ensures that the parent cell and new daughter cells have the same genetic information (same number of chromosomes)

Question 16

What are sister chromatids?

Answer 16

identical copies of chromosomes attached by the centromere

Question 17

When does the nuclear envelope break down?

Answer 17

prophase

Question 18

When do the sister chromatids line up at the equator?

Answer 18

metaphase

Question 19

When does the nucleolus disappear and spindles form?

Answer 19

prophase

Question 20

When do 2 nuclei appear?

Answer 20

telophase

Question 21

When do the sister chromatids get pulled apart and move to opposite sides of the cell?

Answer 21

anaphase

Question 22

When does chromatin coil and condense to form chromosomes

Answer 22

prophase

Question 23

When do chromosomes uncoil and turn back into chromatin?

Answer 23

telophase

Question 24

When do spindles shorten?

Answer 24

anaphase

Question 25

When do centrioles move to opposite poles?

Answer 25

prophase

Question 26

In which stages do you have chromosomes instead of sister chromatids?

Answer 26

anaphase and telophase because the sister chromatids have separated and are thus not called sister chromatids anymore...but chromosomes

Question 27

What is mitosis?

Answer 27

nuclear division

Question 28

What is interphase?

Answer 28

preparation for division

Question 29

What is cytokinesis?

Answer 29

cytoplasmic division

Question 30

When does DNA replicate?

Answer 30

during the S phase of interphase

Question 31

When does a cell grow and double its contents including Cytoplasm, proteins and organelles

Answer 31

G1 and G2

Question 32

In which type of cell would you have a cleavage furrow?

Answer 32

animal cell

Question 33

In which type of cell would you have a cell plate?

Answer 33

plant cell

Question 34

Why would a cell plate form over a cleavage furrow?

Answer 34

Because the cell wall is rigid and hard. It is too difficult to pinch inward

Question 35

What causes cancer?

Answer 35

mutations at the DNA level usually for the cyclins (proteins that control the cell cycle)

Question 36

What is a tumor

Answer 36

mass of growing cells

Question 37

Benign tumors are

Answer 37

not cancerous

Question 38

Malignant tumors are

Answer 38

cancerous

Question 39

Metastatic cancer is one in which

Answer 39

the cancer has spread from its original site

Question 40

Slashing refers to

Answer 40

removing the cancer via surgery