the smallest part of an element that can take part in a chemical reaction. All atoms of the same element have the same number of protons in a nucleus
a substance which cannot be further divided into simpler substances by chemical methods; all the atoms in an element contain the same number of protons
metre kilogram starch
glycogen 2
nucleus
1
the process by which different substances mix as a result of random motions of their particles. Diffusion can only take place within or between fluids
2
metre/second
metre/second cell wall, chloroplasts, vacuole 4
organelles, cells, tissues, organs, systems 3
relative mass = 1; relative charge = +1
orbiting the nucleus
mass
Newton
nucleus
nucleus, cytoplasm, cell membrane 6
5
relative mass = 0; relative charge = -1
relative mass = 1; relative charge = 0
acceleration
speed or velocity
cell membrane
cytoplasm 8
7
the total number of protons and neutrons present in the nucleus of an atom
the number of protons in the nucleus of an atom. It is also the number of electrons present in an atom and the position of the element within the Periodic Table
speed = distance / time
force
cell wall
cell membrane 10
9
the average mass of an atom of an element, taking account of the isotopes of the element, on a scale where carbon-12 has a mass of exactly 12
atoms of the same element which have different numbers of neutrons in their nuclei; they differ in their mass numbers
0 m/s
velocity is the speed in a certain direction
photosynthesis
cell wall 12
11
2
1
1200 m
6 m/s
plant leaf cell
the vacuole 14
13
2,2
2,1
acceleration = (change in velocity) / time
50 s
increase the surface area of absorption
plant root hair cell 16
15
2,4
2,3
it is getting faster
a is 'acceleration'; u is 'initial velocity'; v is 'final velocity'; and t is 'time'
red blood cell 18
animal sperm cell 17
2,6
2,5 2
4 m/s
it is slowing down
brick red
iodine 20
19
2,8
2,7 2
answer: -3 m/s 20 m/s
a substance that increases the rate of a chemical reaction without being used up itself
enzymes 22
2,8,2
21
2,8,1
enyzmes denature
animal body temperature (37oC) 24
23
2,8,4
2,8,3
the gradient of the line
the object has a constant velocity
carbon, hydrogen and oxygen
carbon, hydrogen and oxygen 26
2,8,6
25
2,8,5
starch or glycogen
carbon, hydrogen, oxygen and nitrogen 28
2,8,8
27
2,8,7
lipids
proteins 30
29
2,8,8,2
2,8,8,1
Stage A: constant acceleration Stage B: acceleration is zero Stage C: constant negative acceleration (less than in stage A) osmosis is the diffusion of water through a semipermeable membrane from a dilute to a more concentrated solution.
diffusion is the net movement of particles from a region in which they are in higher concentration to regions of lower concentration
31 32
2
a Period
900 metres
the total distance travelled
diffusion, osmosis, and active transport
active transport is the net movement of a substance against its concentration gradient by use of energy from respiration
34
33
4
3
0 Newtons
the one force that has the same effect as all the forces combined
rate of diffusion will increase 36
surface area to volume ratio, temperature, and concentration gradient 35
one electron in outer shell
Groups
0 Newtons
it will continue at the same velocity
the difference in concentration of a substance between two sides of a membrane
rate of diffusion will increase 38
noble gases: elements in Group 0 - agroup of stable, very unreactive gases
37
seven electrons in the outer shell
the maximum velocity of a falling body when resultant force equals zero
F = ma
light energy
smaller 40
39
good conductors or heat and electricity; shiny when cut; malleable; ductile; sonorous; form positive ions
they have full outer shells/ they have 8 electrons in the outer shell
4000 Newtons
2.5 m/s
carbon dioxide and water
chemical energy
2
42
carbon (in graphite form)
41
Poor conductors heat and electricity; dull; crumply; form negative ions
W = mg
2
2
9.8 m/s (accept 10 m/s ) carbon dioxide plus water gives glucose and oxygen 44
chlorophyll 43
elements in Group 7 of the Periodic Table - generally the most reactive group of non-metals
elements in Group 1 of the Periodic Table, they are the most reactive group of elements
kinetic energy increases by x4
98 Newtons (accept 100 N)
carbon dioxide concentration, light intensity and temperature
C6H12O6 45 46
1+ because it has lost one electron
charged particles made from an atom, or group of atoms (polyatomic ions), by the loss or gain of electrons - the gain of electrons produces negative ions; the loss of electrons produces positive ions
the mass of the car, the speed of the car, and the road conditions
kinetic energy to prevent the leaf from losing water 48
carbon dioxide, water, light 47
1+ because it has lost one electron
1+ because it has lost one electron
the turning effect of the force
the drivers reaction time
open or close the stomata pores to regulate gas (and water) movement
allow carbon dioxide to enter the leaf and oxygen to leave
50
49
1- because it has gained one electron
2+ because it has lost two electrons
Ncm or Nm (Newton centimetres or Newton metres)
moment = force x perpendicular distance from the pivot
they are rich in chloroplasts 52
most of the photosynthesis takes place in the palisade cells 51
1+ because it has lost one electron
1- because it has gained one electron
10 Nm clockwise
3 Nm
they are needed to make amino acids
they are needed for chorophyll 54
53
2+ because it has lost two electrons
2+ because it has lost two electrons
length minus original length
the point in a body where all the weight can be considered to act from
all the time 56
starch 55
either 2+ or 3+ because it has either lost two or three electrons
either 1+ or 2+ because it has either lost one or two electrons extension is proportional to load, provided elastic limit is not exceeded
one that returns to its original length when the applied force is removed
photosynthesis is greater than respiration during the day but at night photosynthesis stops and respiration is the only process
carbohydrate 58
57
1- because it has gained one electron
2- because it has gained two electrons
no
one that stays deformed when the applied force is removed
protein 60
any two from: sugar, fruit, vegatable, potato, rice, wheat, bread 59
1+ because it has lost one electron
1- because it has gained one electron a straight line through the origin
electric current any two from: meat, fish, cheese, eggs, beans and nuts
lipids (fats and oils) 62
61
3+ because it has lost three electrons
1+ because it has lost one electron
A
I
night blindness
meat, butter, cheese, milk, eggs, fish, olive oil, margarine
64
63
(i) a reaction in which oxygen is removed from a compound
(i) a reaction in which oxgen is added to an element or compound
(ii) a reaction involving the gain of electrons by an atom, molecule or ion
(ii) a reaction involving the loss of electrons from an atom, molecule or ion
Q
electric charge
scurvy
carrots, fish liver oil, liver, butter, margarine 66
65
strong bonds between ions
It has an ionic structure or strong bonds between ions
energy
C
making teeth and bones
fresh fruit, vegetables 68
Ions are free to move
67
a strong electrostatic force of attraction between oppositely charged ions - this type of bonding exists for most metallic compounds
J E dairy products, fish, bread, vegatables 70
helps carry oxygen in red blood cells 69
1+
a process in which a chemical reaction is caused by the passage of an electric current
t
time
it gives the muscles of the gut something to push against as food is moved through the intestine
red meat, liver, eggs, spinach 71 72
2-
2+
electric resistance
s
secrete enzymes onto food
oesophagus, stomach, small intestine, large intestine 74
73
1-
R 立 mechanical 75
ingestion 76
V
voltage (or potential difference)
egestion
the process of breaking food down into small molecules that can be absorbed through the wall of the gut
78
77
power V waves of muscle contraction that pass food down the gut 80
excretion 79
P W amylase and maltase
the movement of food doesn't depend on gravity 82
81
Little attraction between individual molecules
P=3W
lipase
I=5A 84
protease 83
very strong giant covalent bonds
graphite and diamond
current equals six amperes
resistance equals four ohms
gall bladder
liver 86
the direct change of state from solid to gas. The liquid phase is passed by. Graphite and diamond sublime
85
layers of carbon atoms slide over each other
time equals two seconds P=IxV neutralises stomach acid and breaks up lipids villi
87 88
the measure of the amount of substance in chemistry. One mole of a substance has a mass equal to its relative formula mass in grams
very strong giant covalent bonds
E=IxVxt V=IxR increases surface area of intestine 89
energy 90