4.2 Cell Division and Stem Cells

Question 1

Why are we not an identical copy of our mother/father?

Answer 1

because we inherit half chromosomes from our mother and half from our father

Question 2

What is mitosis?

Answer 2

A type of cell division which ensures that when a cell divides, each new cell produced has the same genetic information

Question 3

Name three functions of mitosis?

Answer 3

growth of an organism
organisms needs to replace worn out cells
organisms need to repair damaged tissue

Question 4

How many daughter cells are produced in mitosis?

Answer 4

2

Question 5

How do the genes in the daughter cells compare to the parent cell? (mitosis)

Answer 5

The genetic information must be identical to the mother cell, and the number of chromosomes.

Question 6

If the parent cell had 46 chromosomes, how many chromosomes would each of the daughter cells have? (mitosis)

Answer 6

46

Question 7

What happens in sexual reproduction?

Answer 7

The nucleus of a male gamete fuses with the nucleus of a female gamete, producing a new cell called a zygote

Question 8

Name the gametes in plants

Answer 8

pollen and eggs

Question 9

How many chromosomes are found in human gametes?

Answer 9

23

Question 10

Explain why gametes have 23 number of chromosomes?

Answer 10

so that when the male gamete can fuse with the female gamete, they have the correct number of chromosomes for that organism

Question 11

What is meiosis?

Answer 11

A type of cell division that makes gametes

Question 12

Name the function of meiosis

Answer 12

to make sex cells

Question 13

How many daughter cells are produced in meiosis?

Answer 13

4

Question 14

How do the genes in the daughter cells compare to the parent cell? (meiosis)

Answer 14

They are genetically different as they have half the number of chromosomes.

Question 15

What are the benefits of using your own stem cells?

Answer 15

no rejection
no need to find a donor
no need for tissue typing

Question 16

What are 3 clinical problems with collecting, storing and using stem cells

Answer 16

1. need to be collected before birth for embryonic stem cells
2. mutations could occur in stem cells cultured for a number of generations
3. cultured stem cells could be contaminated with viruses

Question 17

Why do some people not agree with the use of embryonic stem cells?

Answer 17

It is the destruction of potential life

lead to ethical objections

Question 18

State ways doctors can use stem cells to treat patients

Answer 18

repair tissue
replace damaged tissue
can be transplanted into patients to treat medical conditions (bone marrow transplant, Parkinson’s )

Question 19

State the name of the disease that can occur if cell division by mitosis is uncontrolled

Answer 19

cancer

Question 20

What general name is given to cells such as embryonic human cells?

Answer 20

stem cells

Question 21

What features of stem cells could make them useful in treating many different medical conditions?

Answer 21

undifferentiated/not specialised

can differentiate into different kinds of tissues

Question 22

Where do plants have stem cells?

Answer 22

In the Meristem (tip of the shoot and tip of the root)

Question 23

Name three lifestyle factors that can increase the risk of cancer

Answer 23

Alcohol intake
Exposure to ionising radiation
smoking

Question 24

What are carcinogens?

Answer 24

Chemicals and other agents that can cause cancer

Question 25

What are stem cells?

Answer 25

unspecialised cells capable of developing into many different types of cell

Question 26

What is an undifferentiated cell?

Answer 26

Has the ability to divide into any type of cell

A cell which has not yet become specialised

Question 27

What are embryonic stem cells?

Answer 27

if cells are removed from the embryo they will differentiate into any cell type

Question 28

Name four places where you find adult stem cells

Answer 28

eyes
heart
skin
brain