Y9 SUMMER EXAM MARKSCHEME (HIGHER)
BIOLOGY
M1.(a) (i)release energy
allow provide / supply / give energy
donot accept produce / create / generate / make energy
donot allow release energy for respiration
1
(ii)contain half the (number of) chromosomes or contains
one set of chromosomes or contains 23 chromosomes
allow genetic information / DNA / genes / alleles instead of chromosomes
accept haploid
1
(b) any two from:
•(stem cells) are unspecialised / undifferentiated
allow description eg ‘no particular job’
•are able to become differentiated
or can form other types of cell / tissue / organ
•stem cells can / able to divide / multiply
2
[4]
M2.Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Examiners should also apply a ‘best-fit’ approach to the marking.
0 marks
No relevant content.
Level 1 (1 – 2 marks)
An example is given of a named substance
or
a process
or
there is an idea of why diffusion is important eg definition.
Level 2 (3 – 4 marks)
At least one example of a substance is given
and
correctly linked to a process in either animals or plants.
Level 3 (5 – 6 marks)
There is a description of a process occurring in either animals or plants that is correctly linked to a substance
and
a process occurring in the other type of organism that is correctly linked to a substance.
examples of points made in the response
Importance of diffusion:
•to take in substances for use in cell processes
•products from cell processes removed
Examples of processes and substances:
•for gas exchange / respiration: O2 in / CO2 out
•for gas exchange / photosynthesis: CO2 in / O2 out
•food molecules absorbed: glucose, amino acids, etc
•water absorption in the large intestine
•water lost from leaves / transpiration
•water absorption by roots
•mineral ions absorbed by roots
extra information
Description of processes might include:
•movement of particles / molecules / ions
•through a partially permeable membrane
•(movement of substance) down a concentration gradient
•osmosis: turgor / support / stomatal movements
[6]
M3. (a)because water enters (the cell / it / named cell)
donot accept salt / sugar / solution entering
1
by osmosis / diffusion
if osmosis / diffusion not given accept concentration inside cell greater than outside cell
assume concentration refers to solute concentration unless answer indicates otherwise
allow water goes up the concentration gradient
allow water goes down its concentration gradient
donot accept if diffusion of salt / sugar
1
through a partially permeable membrane
allow semi / selectively permeable membrane or description
1
(b) (plant cells) have (cell) wall
accept animal cells have no (cell) wall
ignore reference to cell membrane
donot accept reference to other organelles or any implication that animal cells have a cell wall eg plant cells have a thicker cell wall
1
[4]
M4.only 24 students tested or only one test or reference to lack of controls eg gender / age
1
students could drink as much water as they wanted
or
some students drank more water than others
or
some students drank water and beer
1
differences only slight
ignore effects of beer or promotion of beer drinking
1
[3]
M5. (a)anytwo from:
•sterilise / kill microorganisms
ignore ‘cleaning’ / ‘disinfect’
ignore ‘germs’
•method of sterilisationeg apparatus / media sterilised in oven / autoclave
allow pressure cooker / boiling water
• pass flask mouth / pipette tip / loop / test tube mouth through flame
•work near a flame
•minimise opening of flask / test tube or hold non-vertical
allow idea of sealing / covering or prevent entry of air
2
(b)anytwo from:
•temperature
ignore references to time / type of bacterium
•concentration / amount of nutrients / ions
•type of nutrient
•volume / amount of solution
•amount of bacteria added
•agitationor amount of oxygen
2
(c) (i) 7.5
accept in range 7.4 – 7.6
1
(ii)use more pH values around / close to pH 7.5 / between 7 and 8
1
[6]
M6. (a) No
no mark
if yes max 1 for correct statement
diffusion is down the concentration gradient
accept by diffusion ions would leave the root
1
to enter must go up / against the concentration gradient
or concentration higher in the root
or concentration lower in the soil
1
(b) (i) 0.9 or 3.25
for correct answer with or without working
if answer incorrect 1.3 or their rate – 0.4 gains 1 mark
or130 – 40 or 90 gains 1 mark
2
(ii) (uptake) by active transport
1
requires energy
more energy from aerobic respiration
1
or
more energy when oxygen is present
1
[7]
CHEMISTRY (HIGHER)
M7. (a)positive / + / 2
gains 1 mark
but 2+ / ++ / +2
gains 2 marks
2
(b)Ideas that: 2
Ca2+
Br- [Do not disqualify for "bromine" ions]
Ions / They are in the ratio 1:2
any two for 1 mark each
2
[4]
M8. (a) 2,4 (drawn as crosses) on shells
accept dots / e / - etc.
1
(b)(i) hard
allow rigid / high melting point
donot allow references to bonding
ignore strong
ignore unreactive
ignore structure
1
(ii)anythree from
max2 if ionic / metallic / molecule / intermolecular bonds or incorrect number of bonds
•giant structure / lattice / macromolecular
allow many bonds
•covalent (bonds)
•(covalent) bonds are strong
accept needs lots of energy to break bonds (owtte)
•(each) carbon / atom forms four bonds
or
(each) carbon / atom bonded to four other atoms
3
(c) anythree from:
max2 if ionic / ions / metallic / molecule
‘it’ needs to be qualified
graphite
•has delocalised / free electrons
donot accept the electrons move unless qualified (around structure etc)
or
electrons that can move through / around the structure
•each carbon is joined to three other carbon atoms
allow graphite has three bonds
or
one electron from each atom is free / delocalised
diamond
•has no free / delocalised electrons
donot accept the electrons do not move
or
no electrons that move around the structure
•all the electrons are used for bonding
allow diamond has 4 bonds
or
each carbon joined to four other carbon atoms
3
[8]
M9. (a) (i)
1
(ii)nucleus
1
(b)it has 2 more neutrons or converse
or
O-16 has 8 neutrons (1 mark)
O-18 has 10 neutrons (1 mark)
2
[4]
M10 (a) 2.8.3 on diagram as Xs / dots
or e
accept paired or unpaired
1
(b)anytwo from:
•electrons in highest energy level or electrons in outer shell
•electrons are delocalisedor sea of electrons
•electrons are free or electrons move around / flow
•electrons carry charge / current
ignore carry electricity
2
[3]
M11.(bronze is) hard(er)
a statement about hardness or strength is required for all 5 marks
accept corrosion resistance
ignore reference to rust
allow strong(er)
1
(copper)
(the atoms are arranged) in layers (therefore) the layers / atoms can slide over each other (making it softer)
accept a correct diagram with annotation / labels
1
1
(bronze)
thetin atoms distort the layers / structure
accept a correct diagram with annotation / labels
1
or
different sized atoms distort the layers / structure
(so) the atoms / (distorted) layers cannot slide over each other (making it harder)
donot allow stronger bonds
1
[5]
M12. (a)anyfour from:
max3 marks if any reference made to covalent / ionic bonding / molecules or intermolecular forces or graphite / diamond or forces of attraction between electrons and then ignore throughout
•giant structure / lattice
ignore layers
•positive ions
•sea of electrons ordelocalised / free electrons
ignore electrons can move
•awareness of outer shell / highest energy level electrons are involved
•(electrostatic) attractions / bonds between electrons and positive ions
•bonds / attractions (between atoms/ ions) are strong
allow hard to break for strong
ignore forces unqualified
•a lot of energy / heat is needed to break these bonds / attractions
ignore high temperature
4
(b)(i) that they are very small
accept tiny / really small / a lot smaller / any indication of very small
eg microscopic, smaller than the eye can see
or
1–100 nanometresor a few (hundred) atoms
ignore incorrect numerical values if very small is given
1
(ii)any2 from:
•one (non-bonded) electron from each atom
•delocalised / free electrons
allow sea of electrons
ignore electrons can move
•electron carry / form / pass current / charge
ignore carry electricity
2
[7]
PHYSICS
M13.(a) (i)p.d. is (directly) proportional to current
or
gradient / slope is constant
or
the lines show constant resistance
accept lines are straight / diagonal
1
(ii)C
reason only scores if C is chosen
1
for the same p.d. the current is the smallest
accept lowest gradient and the gradient = 1 / R
1
(b) (i) ohm
accept correct symbol Ω
accept an answer written in the table if not given in answer space
1
(ii)K and L
reason only scores if both K and L are chosen
1
only length varies
accept type of metal and the diameter are the same
1
(iii)measure the resistance of more wires made from different metals
accept test more (types of) metals
measure the resistance of more wires is insufficient
they only use two metals is insufficient
1
(c) (i) voltmeter symbol correct and drawn in parallel with the wire
accept voltmeter symbol correct and drawn in parallel with the battery
1
(ii)correct symbol drawn
symbol must be rectangular
1
[9]
M14.(a) (i)also double
increases is insufficient
1
(ii)variable resistor
accept rheostat / potentiometer
1
(b)(i) the data / results / variables are continuous
accept data / results / variables are not categoric / discrete
1
(ii)misreading the ammeter
donot accept misreading the meter / results
donot accept misreading the ammeter and / or voltmeter
reading / human error is insufficient
1
(iii)straight line from the origin drawn passing close / through
points at 1 V, 5 V, 6 V and ignoring anomalous point
donot accept line drawn ‘dot-to-dot’
1
(iv)yes
mark is for the reason
supportspredictionor(straight) line passes through the origin
accept a mathematical argument, eg when p.d. went from 2 to 4 the current went from 0.3 to 0.6
it’s directly proportional is insufficient
1
[6]
M15. (a)ordinary cell has higher voltage (normally / at start)
or
ordinary cell 1.3V nicad 1.2V (normally / at start)
for 1 mark
voltage of ordinary cell falls more slowly
gains 1 mark
(accept ordinary cell lasts longer)
but
as above with relevant quantification e.g. falls to zero in 60 seconds
compared to 6 seconds
or
nicad falls to zero 10 times as fast
gains 2 marks
3
(b) (i) answer in range 32-34 (seconds) (inclusive)
gains 1 mark
but
answer in range 22-24 (seconds) (inclusive)
gains 2 marks
(ii) 12 (seconds)
gains 1 mark
but
2 (seconds)
gains 2 marks
4
(c)resistance of the lamp / filament changes / increases
gains 1 mark
but
resistance of the lamp / filament decreases
gains 2 marks
because the temperature of the filament falls / filament cools
for 1 mark
3
[10]
M16. (a)
3
one mark for each symbol
allow more than 2 cells joined
max. 2 marks if symbols incorrectly allow rheostat arrow in either direction
(b)current will decrease
1
since resistance greater
1
[5]