unit 2 test- mitosis

Question 1

Why do cells have to divide?

Answer 1

1) Has more trouble moving necessary items across the cell membrane
2) Cell gets too big, places too much on the DNA (DNA overload)

Question 2

What is DNA overload?

Answer 2

When a cell becomes too large and places many demands on the cell’s DNA

Question 3

In a living cell, what part of the cell represents surface area and which part of the cell represents volume?

Answer 3

Surface area: total area of the cell membrane
Volume: cytoplasm

Question 4

Cell division occurs in two main stages. What are they?

Answer 4

Mitosis and cytokinesis

Question 5

What is the cell cycle?

Answer 5

The series of events that takes place in a cell as the cell grows and divides

Question 6

What are the 4 stages of the cell cycle?

Answer 6

G1, S, G2, and M

Question 7

What is G1 phase?

Answer 7

cell growth, synthesizes new proteins and organelles

Question 8

What is S phase?

Answer 8

DNA replication, DNA is synthesized as chromosomes are replicated

Question 9

What is G2 phase?

Answer 9

prepping for cell division, shortest phase

Question 10

What is M phase?

Answer 10

mitosis, splitting a cell into two daughter cells

Question 11

What is G0 phase?

Answer 11

The phase when a cell is not in the replicative cell cycle

Question 12

What are 3 cells that can go into G0 phase indefinitely?

Answer 12

Heart cells, nerve cells, red blood cells

Question 13

Cells spend most of their lifetime in what stage?

Answer 13

Interphase

Question 14

What phases of the cell cycle does interphase include?

Answer 14

G1, S, and G2

Question 15

What are the 4 stages of mitosis in order?

Answer 15

PMAT, prophase, metaphase, anaphase, telophase

Question 16

What happens during prophase?

Answer 16

Chromosomes become visible as tightly coiled threadlike structures

Question 17

What happens during metaphase?

Answer 17

Nucleus dissolves, chromosomes condense and move towards the center of the cell

Question 18

What happens during anaphase?

Answer 18

The sister chromatids separate from each other and are pulled towards opposite ends of the cell

Question 19

What happens during telophase?

Answer 19

Chromosomes spread out into a tangle of chromatin and mitosis is complete

Question 20

How are chromatin and chromosomes different in structure?

Answer 20

Chromatin: spread out and messy
Chromosomes: bundled in an X shape

Question 21

How are chromatin and chromosomes different in appearance?

Answer 21

Chromatin: Long, thin, loosely coiled
Chromosomes: supercoiled, compact

Question 22

How are chromatin and chromosomes different in organisation?

Answer 22

Chromatin: not organised, spread throughout nucleus, easier for replication and transcription
Chromosomes: organised, necessary for replication

Question 23

How are chromatin and chromosomes different in presence in a cell?

Answer 23

Chromatin: found throughout interphase
Chromosomes: seen only during cell division

Question 24

How are chromatin and chromosomes different in visualisation on a microscope?

Answer 24

Chromatin: beads on a string when stained and under a powerful electron microscope
Chromosomes: can be seen with a powerful light microscope

Question 25

What does an unduplicated chromosome look like?

Answer 25

< or >

Question 26

What is the name of the proteins that regulate the cell cycle?

Answer 26

Cyclins

Question 27

Define cancer?

Answer 27

Disease of the cell cycle, cells divide uncontrollably and do not die, they are immortal

Question 28

What are tumors?

Answer 28

Tumors are clumps of cancer cells

Question 29

What causes cancer?

Answer 29

Genetics, exposure to chemical or other genetic factors, viruses and/or lifestyle (not exercising, sleeping badly, eating badly, etc)

Question 30

What are the 3 most common ways to treat cancer?

Answer 30

Surgery, chemotherapy, radiation

Question 31

Where is the centromere in a chromosome?

Answer 31

In the middle of the X shape

Question 32

Where are the sister chromatids?

Answer 32

> < those guys are the sister chromatids before they connect and make a chromosome

Question 33

Where are the telomeres?

Answer 33

At the ends of each leg (feet of the chromosome)

Question 34

How is 6 feet of DNA into the nucleus of a cell?

Answer 34

DNA wraps around proteins called histones. DNA in groups of 8 histones are called nucleosomes and the DNA further wraps around them. This is called chromatin, chromatin is loosely coiled. When a cell is starting mitosis, chromatin becomes chromosomes which are supercoiled.

Question 35

How many chromosomes are in the human body?

Answer 35

46

Question 36

How many chromosomes are in a human sex cell (egg/sperm)?

Answer 36

23

Question 37

What is angiogenesis?

Answer 37

New blood growth

Question 38

What is a benign tumor?

Answer 38

A tumor that stays in one spot

Question 39

What is a malignant tumor?

Answer 39

It has metastasised (left tumor site and spread)

Question 40

What is apoptosis?

Answer 40

Programmed cell death, normal cells will die, cancer cells will not die.

Question 41

What is DNA in a group of 8 histones called?

Answer 41

Nucleosomes