Module 2 chapter 6

Question 1

What are the 2 main stages of the cell cycle in a eukaryotic cell

Answer 1

• Interphase

- Mitotic (division) phase

Question 2

What phase does the cell spend most of it’s time in

Answer 2

Interphase

Question 3

Why is interphase often referred to as resting phase

Answer 3

As cell are not actively dividing

Question 4

What makes interphase a very active part of the cycle

Answer 4

the cell is carrying out all it’s major functions

Question 5

What are a cells major functions during interphase

Answer 5

• Producing enzymes or hormones

- preparing for cell division

Question 6

What are the 3 main stages of interphase

Answer 6

• G1
• S
• G2

Question 7

What is G1 phase

Answer 7

the first growth phase

Question 8

What is G2 phase

Answer 8

second growth phase

Question 9

What is S phase

Answer 9

Synthesis phase

Question 10

What happens in G1 phase

Answer 10

organelles synthesis from proteins and replicate

Cell increases in size

Question 11

What happens in S phase

Answer 11

DNA is replicated in the nucleus

Question 12

What happens in G2 phase

Answer 12

• cell continues to increase in size
• energy stores are increased
• Duplicated DNA is checked for errors

Question 13

Where does proteins synthesis occur is interphase

Answer 13

Cytoplasm

Question 14

What 2 phases does the mitotic phase go through

Answer 14

• Mitosis

- Cytokinesis

Question 15

What happens in the mitosis stage

Answer 15

-Nucleus divides

Question 16

What happens in the cytokinesis stage

Answer 16

the cytoplasm divides and 2 cells are produced

Question 17

What occurs in the G0 phase

Answer 17

the cell leaves the cycle

Question 18

When the cell leaves the cycle in G0 phase is it temporary or permanently

Answer 18

It can be either

Question 19

What are the 3 reasons for the cell leaving the cycle

Answer 19

• Differentiation
• DNA of a cell may be damaged
• Aging

Question 20

What have a growing number of senescent cells been linked to

Answer 20

aged related diseases: cancer and arthritis

Question 21

When a cell is differentiated why won’t it enter the cell cycle again

Answer 21

It becomes specialised to carry out that function indefinitely

Question 22

What happens when a cell’s DNA is damaged

Answer 22

no longer divide and enters a period of permanent cell arrest

Question 23

What are the control mechanisms of the cell cycle

Answer 23

Checkpoints

Question 24

What do checkpoints do in the cell cycle

Answer 24

monitor and verify if each phase of the cycle has been accurately completed before the next stage

Question 25

Where are the 3 check points

Answer 25

- G1 checkpoint - G2 checkpoint - spindle assembly checkpoint

Question 26

What does the G1 checkpoint check for

Answer 26

- Cell size - nutrients - growth factors - DNA damage

Question 27

What does the G2 checkpoint check for

Answer 27

- cell size - DNA replication - DNA damage

Question 28

What does the spindle assembly checkpoint check for

Answer 28

Chromosome attachment to spindle

Question 29

What checkpoint does the cell have to pass for mitosis to proceed

Answer 29

Spindle assembly checkpoint

Question 30

What does the term mitosis usually refer to?

Answer 30

the whole of cell division

Question 31

What is cytoplasmic division called

Answer 31

cytokinesis

Question 32

What happens to the cell when it divides by mitosis

Answer 32

It produces 2 genetically identical daughter cells

Question 33

What is mitosis an important process in

Answer 33

- growth - tissue repair - asexual reproduction

Question 34

What are the 4 stages of mitosis

Answer 34

- prophase - metaphase - anaphase - telophase

Question 35

What practical would you do to study mitosis

Answer 35

Prepar stained squash slides of root cells

Question 36

What does the term mitotic index mean?

Answer 36

the ratio between the number of cells undergoing mitosis and the total population of the cells

Question 37

How would you calculate the mitotic index

Answer 37

the number of cells undergoing mitosis divided by the total number of cells

Question 38

When does meiosis occur

Answer 38

in gamete formation

Question 39

How many nuclear divisions does meiosis consist of

Answer 39

2

Question 40

How many daughter cells are produced as a result of meiosis

Answer 40

4 daughter cells

Question 41

What are some differences between mitosis and meiosis

Answer 41

Daughter cells aren't genetically identical and have half the number of chromosomes the parent cell had

Question 42

What is meiosis important for

Answer 42

- maintaining the chromosome number from one generation to the next - induces genetic variation from one generation to the next

Question 43

What's the difference between chromosomes and chromatids

Answer 43

Chromosomes consists of 1 stand of DNA | Chromatids consists of 2 molecules of double stranded DNA

Question 44

What's the structure of a chromatid

Answer 44

thin and long fibrus structure

Question 45

What's the structure of a chromosome like

Answer 45

thin and ribbon like structure

Question 46

What is a diploid

Answer 46

A cell or organism that has paired chromosomes one from each parent

Question 47

What is an example of a dipoid

Answer 47

Human egg and sperm cell

Question 48

What is a haploid

Answer 48

When a cell has half the number of chromosomes

Question 49

What division type would a haploid cell go through

Answer 49

Meiosis

Question 50

What is crossing over in meiosis

Answer 50

2 chromosomes of homologous pair exhange equal segments with each other

Question 51

When does crossing over occur

Answer 51

First divion of mieosis

Question 52

What has the chromosome done at the first division of meiosis

Answer 52

Replicated into 2 strands called sister chromatids

Question 53

How does crossing over cause genetic variation

Answer 53

creates new combinations of genes in the gametes that are not found in either parent , thus genetic diversity

Question 54

What happens to cells that leave the cell cycle

Answer 54

they become specialised and develop specific cellular structures

Question 55

In multicellular organisms do cells work together or alone

Answer 55

rarely work alone and are organised into groups

Question 56

Where are similar cells grouped together

Answer 56

In tissues and different tissues are organised into organs

Question 57

What do various organs work together to make

Answer 57

Organ systems, many organ systems make up the organism

Question 58

What is a specialised feature of a red blood cell

Answer 58

- Contain haemoglobin - No nucleus - bi-concave

Question 59

What are the specilised features of a root hair cell

Answer 59

- Large surface area | - lots of mitocondria