B2 Cell division and repro

Question 1

What is cell division?

Answer 1

The process by which a parent cell divides into two daughter cells.

Question 2

What is the name of cell division?

Answer 2

Mitosis (remember tho cytokinesis is the but where the cells splits)

Question 3

What is a chromosome?

Answer 3

A thread-like structure in the nucleus that carries genes (instructions for the cell).

Question 4

What is the cell cycle?

Answer 4

The full life of a cell. It grows, copies its DNA, then divides into two new cells.

Question 5

What are the main stages of the cell cycle?

Answer 5

1.Interphase (growth + DNA replication)
2. Mitosis (nucleus divides)
3.Cytokinesis (cell splits)

Question 6

What happens in interphase?

Answer 6

The cell grows and makes a copy of its DNA (so it has double before dividing).

Question 7

Why does the cell need to replicate eveything before mitosis?

Answer 7

So that each new cell gets a full set of DNA and all the parts it needs to work properly.

Question 8

What is mitosis?

Answer 8

When the nucleus splits so each new cell gets the right DNA.

Question 9

What is cytokinesis?

Answer 9

What is cytokinesis?

Question 10

What is the stages of mitosis?

Answer 10

Prophase
Metaphase
Anaphase
Telophase

Question 11

What happens in prophase?

Answer 11

DNA gets packed into chromosomes and the nucleus starts to break down.

Question 12

What happens in metaphase?

Answer 12

Chromosomes line up in the middle of the cell.

Question 13

What happens in anaphase?

Answer 13

The chromosomes are pulled apart to each side of the cell.

Question 14

What happens in telophase?

Answer 14

A new nucleus forms around each set of chromosomes.

Question 15

Is cytokinesis part of mitosis?

Answer 15

No, but it happens right after mitosis. It’s part of the cell cycle.

Question 16

Why is mitosis important?

Answer 16

It helps with growth, repair, and making new cells.

Question 17

How many chromosomes do body cells have?

Answer 17

46 (in 23 pairs)

Question 18

How many chromosomes do gametes have?

Answer 18

23 (not in pairs)

Question 19

Why do body cells have 46 chromosomes?

Answer 19

Because we get 23 from our mum and 23 from our dad → that makes 23 pairs (46 total).

Question 20

Why do gametes only have 23 chromosomes?

Answer 20

So when fertilisation occurs, the new cell will have 46 chromosomes again.

Question 21

What happens if gametes had 46 chromosomes?

Answer 21

The baby would have too many chromosomes (92!) which could cause serious problems.

Question 22

What are diploid cells?

Answer 22

A cell with 46 chromosomes (23 pairs) — it has 2 copies of each chromosome, one from each parent.

Question 23

What are haploid cells?

Answer 23

A cell with 23 chromosomes — it has only 1 copy of each chromosome.

Question 24

What are an example of diploid cells?

Answer 24

Body cells e.g. muscle cells , blood cells and nerve cells.

Question 25

What are an example of haploid cells?

Answer 25

Gametes.

Question 26

What is growth?

Answer 26

The process of increasing in size (usually permanent).

Question 27

How does growth happen in living things?

Answer 27

By cell division or cell enlargement.

Question 28

What is differentiation?

Answer 28

When cells become specialised to do a specific job.

Question 29

When do animal cells usually differentiate?

Answer 29

At an early stage of life.

Question 30

Why do mature animal cells usually differentiate?

Answer 30

For growth and repair only.

Question 31

Can plant cells specialise all their life?

Answer 31

Yes! Plant cells can differentiate at any time.

Question 32

Where are new, unspecialised plant cells made?

Answer 32

In the meristems (growing areas of stems and roots).

Question 33

What happens in meristems?

Answer 33

Mitosis happens almost all the time to make new cells.

Question 34

What is cloning?

Answer 34

Making an identical copy of an organism without using gametes.

Question 35

Is cloning sexual or asexual reproduction?

Answer 35

Asexual, because there’s no fusion of gametes, and the copies are genetically identical.

Question 36

What is an embryo?

Answer 36

The early stage of development after an egg is fertilised.

Question 37

What is a stem cell?

Answer 37

An undifferentiated cell that can make copies of itself and turn into other types of specialised cells.

Question 38

What can embryonic stem cells do?

Answer 38

They can be cloned and made to differentiate into most types of human cells.

Question 39

Where are stem cells found in adults?

Answer 39

Bone marrow.

Question 40

What can adult bone marrow stem cells become?

Answer 40

They can turn into many types of cells, especially blood cells.

Question 41

Where are plant stem cells found?

Answer 41

Meristems (shots and roots)

Question 42

What can meristem cells become?

Answer 42

They can differentiate into any type of plant cell throughout the plant’s life.

Question 43

What conditions might stem cells help treat in the future?

Answer 43

Conditions like diabetes and paralysis.

Question 44

What is research?

Answer 44

Research is the process of studying something to gain new knowledge and understanding.

Question 45

What is the potential of stem cells?

Answer 45

Stem cells can treat serious diseases, help replace organs, and teach us about diseases.

Question 46

Why do some people oppose stem cell use?

Answer 46

Some believe using embryonic stem cells is wrong because it destroys life, while others fear side effects or misuse for money.

Question 47

What is good about embryonic stem cells?

Answer 47

They can turn into any type of cell, which makes them very useful for treating diseases.

Question 48

What is bad about embryonic stem cells?

Answer 48

They are taken from embryos, which some believe is wrong because it ends a potential life.

Question 49

How do embryonic stem cells affect the immune system?

Answer 49

The body may reject them because they aren't a perfect match to the person receiving them.

Question 50

How much do embryonic stem cells cost to collect?

Answer 50

They are expensive to collect because only a few stem cells can be taken from each embryo.

Question 51

What is good about adult stem cells?

Answer 51

They don’t raise ethical issues because they are taken from adults, and they are easier to match with the person’s immune system.

Question 52

What is bad about adult stem cells?

Answer 52

They can’t turn into as many types of cells as embryonic stem cells can, limiting their use.

Question 53

How do adult stem cells affect the immune system?

Answer 53

They are more likely to be accepted by the immune system because they can be taken from the patient themselves.

Question 54

How much do adult stem cells cost to collect?

Answer 54

They are cheaper to collect because it’s easier to gather a lot from one adult.