T1.6 Cell Divison

Question 1

Three main steps of the cell cycle?

Answer 1

Interphase, Mitosis, Cytokinesis

Question 2

4 steps of mitosis in order

PMAT

Answer 2

Prophase, Metaphase, Anaphase, Telophase

Question 3

% of cell cycle spent in interphase

Answer 3

~90% of cell life

Question 4

Two major metabolic activites occuring during interphase

Answer 4

DNA replication and protein synthesis

Question 5

Interphase phases in order

Answer 5

G1, S, G2

Question 6

G1 phase

Answer 6

Growth -> organelles duplicate

Question 7

S phase

Answer 7

Each chromosome is duplicated to create sister chromatids

Question 8

G2 phase

Answer 8

some growth, preparing for divison, checking everything over with cyclins

Question 9

Mitosis

Answer 9

Chromsomes replicate to form sister chromatids so that cell division can occur

Question 10

Prophase

Answer 10

• Chromosomes supercoil and create sister chromatid
• Spindle microtubules/fibers form and reach from poles
• nuclear membrane disintegrate

Question 11

Metaphase

middle

Answer 11

• Sister chromatids align themselves on equator
• fibers attach to centromeres on each chromosome

Question 12

Centromere

Answer 12

Middle of chromosome, where the spindle fibers attach to

Question 13

Anaphase

away

Answer 13

Centromeres divide and chromosomes are pulled to opposite poles

sister chromatids are seperated and called chromosomes again

Question 14

Telophase

Answer 14

chromosomes uncoil, nuclear envelope begins to reappear, looks more seperated

Question 15

Cytokinesis

Answer 15

Divison of the cytoplasm

Question 16

Animal cell cytokinesis

Answer 16

• Clevage furrow created
• Contractile proteins aid in the pinching in of cell membrane

Question 17

Plant Cell cytokinesis

Answer 17

• Vesicles move to equator and fuse together, creating 2 cell membranes.
• Vesicles bring pectin in to be deposited between the two new membranes. Forms the middle lamella
• Cellulose is deposited by exocytosis adjacent to middle lamella, forming the cell wall (cell plate)

Question 18

Is the cell wall intracellular or extracellular

Answer 18

extracellular

Question 19

Cyclins

Answer 19

Ensure that tasks are preformed at the correct time in the cell cycle

Question 20

What are cyclins considered to be?

Answer 20

The “pace-maker” of the cycle

Question 21

Tumor

Answer 21

Abnormal group of cells that develop at stage

Question 22

Maglinant tumor

Answer 22

Life-threatening, cancer, abnormal cells and abnormal growth

Question 23

Benign tumor

Answer 23

Unlikely to do much harm, abnormal growth of normal cells

Question 24

Mutation

Answer 24

a random change to the base sequence of genes

Most gene mutations do not cause cancer

Question 25

Oncogenes

Answer 25

Genes were mutations do cause cancer

Question 26

Carcinogen

Answer 26

chemicaal or agent that causes cancer

Question 27

Mutagens

Answer 27

Agents that cause mutations

Not all are carcinogenic, but are correlated

Question 28

Tumorigenesis

Answer 28

Formation of a tumor

Question 29

Primary tumor

Answer 29

Initial mass of cells created by uncontrolled division of cancer cells

Question 30

Metastasis

Answer 30

Movement of cells from primary tumor to set up a secondary tumor in other parts of the body

Question 31

Steps of metastasis

ALTS

Answer 31

1. Attachment
2. Local breakdown
3. Transport
4. Secondary tumor forms (metastasis)

Question 32

Purpose of mitosis

Answer 32

To ensure that each daughter cell has the correct and identical amount of chromosomes.
Also to divide cell before cell becomes too big

Question 33

Why does supercoiling occur?

Answer 33

Chromosomes may be very large, so if they are coiled very tightly they can be moved around more easily during division

Question 34

Difference between sister chromatids and chromosomes?

Answer 34

Sister chromatids are identical copies of one chromosome being linked by a centromere
Chromosomes are these two chromatids formed together

ngl not sure about this one

Question 35

Mitotic index equation

Answer 35

Total # of cells in a mitosis phase/Total # of cells in the sample

Question 36

% at Rest equation

Answer 36

(Total # of cells in interphase / Total # of cells in the sample) x 100

Question 37

How does cancer develop?

Answer 37

When the cell cycle is improperly regulated, ex: too many stimulating proteins, mutation in oncogenes, and a mutation in tumor suppressor genes

Question 38

Which mitosis phases is the genetic material called sister chromatids?

Answer 38

prophase until they seperate in anaphase