Cells & Control

Question 1

23 chromosomes (haploid male sperm) + 23 chromosomes (haploid female egg) = ???

Answer 1

…= fertilisation

46 chromosomes (diploid)

Question 2

Haploid?

Answer 2

Only one copy of each chromosome

Question 3

Diploid?

Answer 3

Two copies of each chromosome

Question 4

What is a zygote?

Answer 4

Fertilised egg cell

Question 5

What is a cell cycle?

Answer 5

Sequence of growth & division to make new cells

Question 6

Interphase is what?

Answer 6

Cell growth and DNA replication

Question 7

What is mitosis?

Answer 7

Cell division

Question 8

Diploid daughter cells are…?

Answer 8

Genetically identical to each other & the parent cells

Question 9

What are the mitosis stages?

Answer 9

Prophase
Metaphase
Anaphase
Telophase
CYTOKINESIS

Question 10

Cell differentiation?

Answer 10

A cell becomes specialised to perform a specific function

Question 11

Mitosis forms two genetically identical daughter cells

Answer 11

.

Question 12

Growth is caused by…?

Answer 12

Increase in cell number and increase in cell size

Question 13

Meristem cells

Answer 13

Keeps plant growing

Question 14

Guard cells ?

Answer 14

Opening & closing to the stomata, minimise water loss

Question 15

Palisade cells?

Answer 15

Have chloroplasts inside them

Question 16

Xylem vessels?

Answer 16

Transport water using long xylem tissue and cells

Question 17

Root hair cells?

Answer 17

Increases surface area with tiny hairs on the roots, can absorb more water this way.

Question 18

Stem cells - types?

Answer 18

Embryonic - animals
Adult - “

Meristem - plants

Question 19

Advantages of stem cells ?

Answer 19

Used in medicine

Question 20

Disadvantages of stem cells?

Answer 20

Cancer and rejection

Question 21

Embryonic stem cells

Answer 21

• only found in embryos

- they can specialise to form any cell (totipotent)

Question 22

Adult stem cells

Answer 22

• not just found in adults
• means hey are only able to form a few cell types (pluripotent/multi potent)
• found in foetuses and in born organisms too

Question 23

Meristem stem cells

Answer 23

• Source of stem cells in plants
• stem means they can make other cells not that they are in the stem of a plant
• found in tips of the shoot and the root

Question 24

Benefits of stem cells

Answer 24

Long bones -
- bone marrow makes blood cells. Bone marrow cells are adult stem cells and so deities and specialise to form just blood cells

Question 25

Problems of stem cells

Answer 25

Ethics:
Should we use embryonic stem cells from unwanted fertilised eggs from IVF
Cancer:
If the embryonic stem cell,s develop incorrectly then the patient can get a tumor(s)
Rejection:
If the stem cells come from someone else then the body can destroy them