SB1

Question 1

name SI units in order

Answer 1

metre, millimetre, micrometre, nanometre and picometre

Question 2

magnification equation

Answer 2

eyepiece x objective lens

Question 3

definition of resolution

Answer 3

the smallest distance between two points that can still be seen as two points

Question 4

high resolution means

Answer 4

a better detailed image

Question 5

part of a plant cell

Answer 5

cell wall
cell membrane
nucleus
cytoplasm
vacuole
chloroplast
mitochondria

Question 6

parts of an animal cell

Answer 6

cell membrane
cytoplasm
nucleus
mitochondria

Question 7

what’s a specialised cell

Answer 7

cells that have a specific job / function

Question 8

how is the small intestine specialised

Answer 8

microvilli (small folds) which increase the SA and speed up absorption and digestion

lots of mitochondria for it’s muscles as they need energy to squeeze food along

Question 9

how is the sperm cell specialised

Answer 9

streamlined shape to swim and burrow inside the egg cell

mitochondria to release energy and power the tail

tail which moves side to side so the sperm can swim

Question 10

how is the egg cell specialised

Answer 10

cell membrane which hardens after fertilisation

cytoplasm packed with nutrients for embryo growth

Question 11

define eukaryotic and prokaryotic + give an example of prokaryotic cells

Answer 11

eukaryotic cells do have a nucleus, prokaryotic cells do not - eg. bacterial cells

Question 12

what reaction does amylase catalyse
+ where is it found

Answer 12

starch –> small sugars
found in saliva + small intestine

Question 13

what reaction does catalase catalyse
+ where is it found

Answer 13

hydrogen peroxide –> water + oxygen
found in most cells, especially liver

Question 14

what reaction does starch synthase catalyse + where is it found

Answer 14

synthesis of starch from glucose
found in plants

Question 15

what reaction does DNA polymerase catalyse + where is it found

Answer 15

synthesis of DNA from its monomers
found in the nucleus

Question 16

what are starch molecules made of

Answer 16

glucose (molecules)

Question 17

what are protein molecules made of

Answer 17

amino acids

Question 18

what are lipid molecules made of

Answer 18

glycerol and fatty acids

Question 19

what do enzymes work on

Answer 19

substrates

Question 20

what are monomers and polymers

Answer 20

monomers are molecules which join to form a polymer

Question 21

what does iodine test for + what colour change occurs

Answer 21

starch
colour changes from yellow-orange to blue-black

Question 22

what does benedict’s solution test for + what colour change occurs

Answer 22

reducing sugars
colour changes from blue to red

Question 23

what does biurets test test for, what is used in the test + what colour change occurs

Answer 23

proteins
potassium hydroxide + copper sulfate
colour changes from pale blue to purple

Question 24

what does the ethanol emulsion test test for + what change occurs

Answer 24

fats and lipids
lipids present will float to the surface when left to stand

Question 25

what does the ethanol emulsion test test for + what change occurs

Answer 25

fats and lipids lipids present will float to the surface when left to stand

Question 26

how does a calorimeter work

Answer 26

burn a sample of food underneath the calorimeter and measure the temperature change from the water

Question 27

what model shows enzyme action/ activity and where do substrate molecules fit into

Answer 27

lock and key model the active site

Question 28

how is the product molecule formed

Answer 28

substrate molecules fit into the active site, form bonds causing it to no longer fit into the active site and the produce molecule is released

Question 29

what happens if an enzyme denatures

Answer 29

active site becomes damaged and the substrate molecules will no longer fit inside

Question 30

what can cause an enzyme to denature + define optimum pH/ temperature

Answer 30

changes in pH or temperature optimum pH/ temp: conditions which an enzyme works fastest in

Question 31

what happens to an enzyme if temp increases + increases too much

Answer 31

the enzyme will move faster. if it increases too much, the enzyme will denature

Question 32

diffusion

Answer 32

particles move from an area of high --> low conc

Question 33

concentration gradient

Answer 33

difference between two concentrations

Question 34

partially / semi permeable membrane

Answer 34

lets some molecules/ substances through, not others

Question 35

osmosis

Answer 35

movement of water/solvent molecules through a semi permeable membrane from an area of high conc --> low conc

Question 36

active transport

Answer 36

particles move from an area of low conc --> high conc

Question 37

two key points about active transport

Answer 37

requires energy goes against the conc gradient