1 -37

Question 1

What are stem cells
And where are they found

Answer 1

Undifferentiated cells
Embryos, adult animals and meristems in plants

Question 2

3 stages of osmosis

Answer 2

1. DNA and subcellular structures copied
2. chromosomes are pulled to either side of cell and nucleus splits
3. cytoplasm and cell membrane divide

Question 3

what are electron microscopes used for seeing

Answer 3

subcellular structures

Question 4

what microscope came first

Answer 4

light

Question 5

how many um are in 1mm

Answer 5

1000

Question 6

what does um stand for

Answer 6

micro metre

Question 7

magnification equation

Answer 7

image size over actual size

Question 8

when do animal cells differentiate

Answer 8

early in life

Question 9

when do plant cells differentiate

Answer 9

throughout life

Question 10

what are mesophyll cells specialized for

what do they have alot of

Answer 10

photosynthesis
chloroplasts

Question 11

what are sperm cells specialized for
what do they have a lot of

Answer 11

energy production
mitochondria

Question 12

specialized cell def

Answer 12

cell that gained subcellular structures to carry out specific tasks

Question 13

what 2 things do prokaryotic cells have

Answer 13

cytoplasm and cell membrane

Question 14

what is genetic material stored on and where is it held

Answer 14

chromosomes and nucleus

Question 15

what does chlorophyll do

Answer 15

absorb light for photosynthesis

Question 16

what does the vacuole do
(2)

Answer 16

stores cell sap
gives cell structure

Question 17

what do cell walls do

Answer 17

give cell sturcture

Question 18

what takes place in cytoplasm

Answer 18

reactions inside the cell

Question 19

what does the cell membrane control

Answer 19

movement in and out of the cell

Question 20

eukaryotic cell e.g

Answer 20

animal and plant

Question 21

what two things can stem cells found in human embryos do

Answer 21

be cloned
differentiate into any type of human cell

Question 22

what can stem cells be used to treat (2)

Answer 22

paralysis
diabetes

Question 23

risks of using stem cells (2)

Answer 23

transfer of bacteria
ethical and religious objections

Question 24

diffussion def

Answer 24

passive movement of particles from a high concentration to a low
concentration

Question 25

what factors affect the rate of diffusion
(3)

Answer 25

altering concentration gradient, temperature and
surface area

Question 26

what 3 things are specialised for exchanging materials

Answer 26

multicellular organisms, surfaces and organ systems

Question 27

what is the effectiveness of an exchange surface increased by (4)

Answer 27

Having a large surface area
Thin membrane
Efficient blood supply (in animals)
Being ventilated (in animals for gas exchange)

Question 28

what is osmosis

Answer 28

the passive movement of water from an area of higher water concentration
to an area of lower water concentration, across a partially permeable membrane.

Question 29

Mass changes are caused by

Answer 29

the movement of water across a plant cell membrane

Question 30

Active transport uses…

Answer 30

energy from respiration, to transport substances across a membrane from low concentration to high concentration.

Question 31

what is active transport used in

Answer 31

root hair cells and the small intestine for the absorption of nutrients.