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Question 1

why are light microscopes good

Answer 1

they are cheap and you are able to see outlines of cells

Question 2

why are electron microscropes good

Answer 2

allow you to see finer details such as organelles

Question 3

how are electron microscopes better

Answer 3

greater resolving power
higher resolution

Question 4

formula for magnification

Answer 4

imagine size/object size

Question 5

what’s the difference between eukaryotic and prokaryotic cells

Answer 5

eukaryotic have a nucleus, prokaryotic don’t

Question 6

what’s in an animal cell

Answer 6

nucleus
cytoplasm
mitochondria
cell membrane
ribosomes

Question 7

what’s in a plant cell that isn’t in a animal cell

Answer 7

chloroplasts
cell wall
vacuole

Question 8

what’s the purpose of the nucleus

Answer 8

stores DNA
controls all activities of the cell

Question 9

what’s the purpose of cytoplasm

Answer 9

where chemical reactions take place

Question 10

what’s the purpose of mitochondria

Answer 10

aerobic respiration takes place, release energy for the cell

Question 11

what’s the purpose of a cell membrane

Answer 11

a semi-permeable border that controls what goes in and out of the cell

Question 12

what’s the purpose of ribosomes

Answer 12

where proteins are made

Question 13

what’s the purpose of a cell wall

Answer 13

keeps the cells shape turgid (made of cellulose)

Question 14

what’s the purpose of chloroplasts

Answer 14

filled with chlorophyll for photosynthesis

Question 15

what’s the purpose of a vacuole

Answer 15

contains cell sap
keeps the cells shape

Question 16

what is an example of a prokaryotic cell

Answer 16

bacteria

Question 17

what’s in a bacteria cell that is NOT in a plant cell

Answer 17

plasmids
circular strand of DNA
sometimes a flagellum

Question 18

how many pairs of chromosomes are in a human

Answer 18

23

Question 19

how many chromosomes do gametes have

Answer 19

23

Question 20

why are new cells made

Answer 20

growth
repair
development

Question 21

how are new cells made

Answer 21

by mitosis

Question 22

what’s the stages of mitosis

Answer 22

1. nucleus dissolves and genetic material in duplicated
2. two sets of chromosomes move to different sides
3. organelles are duplicated
4. the cell divided producing 2 daughter cells

Question 23

what are some examples of specialised cells

Answer 23

red blood
sperm
root hair

Question 24

where are stem cells found in humans

Answer 24

in adults - bone marrow
embryonic cells

Question 25

where are stem cells found in plants

Answer 25

meristems

Question 26

what can adult cells only differentiate into

Answer 26

red blood cells

Question 27

what are the issues using embryonic cells

Answer 27

it's unethical

Question 28

what is diffusion

Answer 28

the movement of particles from a high concentration to a low concentration - down the concentration gradient

Question 29

does diffusion require energy

Answer 29

hell nah it is passive

Question 30

how can rates of diffusion be changed

Answer 30

-increasing difference in concentration - surface area -temperature

Question 31

what is osmosis

Answer 31

The diffusion of water across a semi-permeable membrane to balance the concentrations of solution inside and outside a cell

Question 32

what happens if the concentration is higher outside the cell

Answer 32

water moves in

Question 33

what is the practical for osmosis?

Answer 33

Weigh and place identical cylinders from same vegetable in sugar solutions of varying concentrations After set time, remove excess water and reweigh Plot % change in mass against concentration To find the concentration in the cells, look at the x axis

Question 34

what's active transport

Answer 34

The movement of particles through a membrane via carrier proteins. This requires energy, and so can go against the concentration gradient.