Mark Scheme – Paper 1 Biology – Double Science FT
Lesson 1
Q1.
(a)     contract / shorten
ignore relax
do not allow expand
1
to churn / move / mix food
accept peristalsis / mechanical digestion
ignore movement unqualified
1
(b)     400
acceptable range 390-410
allow 1 mark for answer in range of 39 to 41
allow 1 mark for answer in range of 3900 to 4100
2
(c)     to transfer energy for use
allow to release / give / supply / provide energy
do not allow to ‘make’ / ߢproduce’ / ‘create’ energy
allow to make ATP
ignore to store energy
1
by (aerobic) respiration or from glucose
do not allow anaerobic
energy released for respiration = max 1 mark
1
(d)     (i)      to make protein / enzyme
ignore ‘antibody’ or other named protein
1
(ii)     too small / very small
allow light microscope does not have sufficient magnification / resolution
allow ribosomes are smaller than mitochondria
ignore not sensitive enough
ignore ribosomes are transparent
1
[8]
Q2.
(a)    B
no mark for “B” alone, the mark is for B and the explanation.
large(r) surface / area or large(r) membrane
accept reference to microvilli
ignore villi / hairs / cilia
accept reasonable descriptions of the surface eg folded membrane / surface
do not accept wall / cell wall
1
(b)    (i)      any one from:
•        (salivary) amylase
•        carbohydrase
1
(ii)     many ribosomes
do not mix routes. If both routes given award marks for the greater.
1
ribosomes produce protein
accept amylase / enzyme / carbohydrase is made of protein
or
(allow)
many mitochondria      (1)
mitochondria provide energy to build / make protein      (1)
accept ATP instead of energy
1
[4]

Lesson 2
Q3.
(a)     
 
 	Mitosis only	Meiosis only	Both mitosis and meiosis	
How cells are replaced		 	 	
How gametes are made	 		 	
How a fertilised egg undergoes cell division		 	 	
How copies of the genetic information are made	 	 		
How genetically identical cells are produced		 	 	
if more than one tick per row then no mark
ignore first row
1
1
1
1
(b)     (i)      (adult) bone marrow
accept (umbilical) cord blood, skin, amniotic fluid / membrane
1
(ii)     cells will not be rejected by the patient’s body (if they have been produced by therapeutic cloning)
allow easier to obtain linked to embryo stem cells
or
(embryo stem cells) can develop into many different types of cells
allow doesn’t need an operation linked to bone marrow
or
(embryo stem cells) not yet differentiated / specialised or undifferentiated
accept embryo cells are pluripotent
1
[6]
Q4.
(a)      A = nucleus
allow phonetic spelling
1
B = (cell) membrane
1
(b)     for repair / growth or to replace cells
ignore new cells / skin
1
(c)     (i)      embryos
1
(ii)     paralysis
1
[5]
Q5.
(a)     2 and 3
1
(b)     cell P has an X chromosome; cell R has a Y chromosome
1
(c)     any two from:
•        (formed from) different egg / 2 eggs
•        (formed from) different sperm / 2 sperm
•        have different genes / alleles / chromosomes / DNA
allow genetics
2
(d)     (i)      stem cells
1
(ii)     the cells divide
1
         the cells differentiate
1
(iii)     (medical) research / named eg growing organs
or
         medical / patient treatment
allow (embryo) cloning
do not allow designer babies / more babies
1
(iv)    any one from:
•        ethical / moral / religious objections
ignore cruel / not natural / playing God
•        potential harm to embryo
allow deformed
ignore harm to mother
1
[9]
Q6.
(a)                 comparisons are not required but should be credited
            accept a clear indication of the statement even if incomplete
can develop into most other types of cell
1
each cell divides every 30 minutes
1
low chance of rejection by the patient’s immune system
1
(b)     any three from:
•        cheaper / only costs £1000
this must be comparative
ignore costs £1000
•        can collect many (stem) cells 
•        adults give permission for their own bone marrow to be collected 
comparisons are not required but should be credited
•        safe
3
[6]

Lesson 3
Q7.
(a)     
 
each extra line negates a mark
4
(b)     pain when urinating
1
yellow discharge
1
(c)     three correct plots
allow 1 mark for two correct plots
2
correctly drawn line
1
(d)     any three from:
•        (fairly) level / steady up to 2009
allow numbers of males fall (slightly) and females rise (slightly) up to 2009
•        (there is a) rise after 2009
•        males are (always) higher than females
•        males rising faster than females
allow overall increase (from 2005 to 2013)
3
(e)     HIV is a virus
1
(and) antibiotics are only effective against bacteria
or
antibiotics do not kill viruses
allow viruses live inside cells
1
[13]
Q8.
(a)     (i)      64
1
(ii)     36
allow e.c.f from (i) i.e. 100 − answer given in (a)(i)
1
(iii)    any one from:
•        only considers 16-year-olds
ignore lack of evidence
allow does not refer to all ages
•        only about some / 5 countries
allow does not refer to all countries.
1
(b)     the more exercise done the healthier a person is
allow the more exercise done the higher the health rating
allow the less exercise done the lower the health rating
1
(c)     having a high cholesterol level
1
(d)     (i)      antibodies
1
(ii)     antibiotics
1
[7]
Q9.
(a)     (i)      56
accept 54 – 58
1
(ii)     increased
1
         reasonable qualification eg slowly then more quickly
           or
           to 174 / 176
           or
           by 138 / 140
1
(b)     any two from:
•        no immunity or antibodies ineffective
accept no resistance
•        no vaccines or humans not immunised
•        idea of large scale contact or large scale travel
do not accept passed on
ignore no cure
2
[5]
Q10.
(a)     any two from:
ignore eating disorder
ignore cancer
•        arthritis 
accept worn joints
•        diabetes 
accept high blood sugar
•        high blood pressure
ignore cholesterol
•        heart disease / heart condition / heart attack / blood vessel disease
allow blood clots / strokes
2
(b)      (i)     or  0.25   or  25%
correct answer gains 2 marks
if answer incorrect, evidence of 1500 ÷ 6000 gains 1 mark
25 without % gains 1 mark
2
(ii)     majority / most / high proportion of people in trial lost mass / weight
ignore good results / it worked
1
Lesson 4

Q11.
(a)     white cells ingest bacteria
produce antibodies which destroy bacteria
produce antitoxins which counteract poisons produced by bacteria
for 1 mark each
3
(b)     dead/mild microbes
stimulate antibody production
white cells can quickly produce these again
for 1 mark each
3
(c)     adds more bacteria (mild) 
does not affect TB bacteria
for 1 mark each
2
[8]
Q12.
(a)      (i)     any one from:
•         cells
•         tissues
•         (live) animals / named
allow mammals
1
(ii)     any three from:
(to test for)
•         toxicity / check not poisonous / not harmful
allow side-effect
allow converse
•         interaction with other drugs
•         efficacy or to see if they work or check if they treat the disease
allow converse
•         dosage or how much is needed
3
(b)     argued evaluation
comparison can be written anywhere in evaluation allow use of ‘only’ for implied comparison for each point eg only statins damage muscles / kidneys / organs
any six from:
•        statin can damage / muscles / kidneys / organs but cholesterol blockers don’t
ignore liver
if neither of the first 2 points are given accept for 1 mark
•        statins can cause death but cholesterol blockers don’t
statins are more dangerous than cholesterol blockers or statins have more side effects
•        cholesterol blockers can interfere with action of other drugs but statins don’t
•        statins are for a life time but cholesterol blockers are not
•        statins (might) reduce cholesterol to zero but cholesterol blockers only 
reduce it or statins reduce cholesterol more
allow statins (might) stop membrane / hormone production but cholesterol blockers don’t
•        statins better for people with inherited high cholesterol
•        cholesterol blockers better for people with dietary cholesterol problems
•        taking/using statins/cholesterol blockers is better than dying from heart 
attack or build up of fat in blood vessels or reduced blood flow
6
[10]

Lesson 5 
13. (a)     points plotted accurately
 square

deduct 1 mark per error
ignore the line
2
(b)     30 or correct from candidate’s graph
accept 30 000 lynx
do not accept 30 000
1
(c)     (i)      fall
mark (i) and (ii) separately
1
(ii)     fewer hares or lack of food
do not accept no hares or food
1
(d)     kills / preys / preys on / hunts / catches
and eats / for food (other) animals
must have the eat and kill for the point
1
[6]
Q14 (a)     any two from:
•        only one ‘chromosome’
allow one strand of DNA
•        circular
allow loop
•        may have plasmids
•        not in a nucleus / no nucleus
2
(b)     (i)      any one from:
•        London is much higher
or converse
•        more variable / wider range
allow ‘on average it is 5 / 6 times greater’
1

(ii)     increases
Included figures must be correct
1
(iii)    overall slight increase
accept ‘doesn’t change much’
1
variable / goes up and down
1
(c)     (i)      both axes correctly labelled
x = Year
y = Number of cases
1
correct points
all correct = 2 marks
1-2 errors = 1 mark
> 2 errors = 0 marks
2
suitable line of best fit
accept straight line or smooth curve
1
(ii)     doesn’t fit the pattern / line of best fit
1
(d)     provides immunity / protection (to TB)
ignore ‘stops people catching it’
ignore ‘resistance’
1
prevents TB spreading
accept ref to herd immunity
1
[13]

Lesson 6
Q15.
(a)     (i)    without oxygen
allow not enough oxygen
ignore air
ignore production of CO2
ignore energy
1
(ii)     more / high / increased lactic acid (at end)
allow approximate figures (to show increase)
ignore reference to glucose
1
(b)     (i)      1.5
allow only 1.5 / 1½ / one and a half
1
(ii)     increases at first and levels off
ignore subsequent decrease
1
suitable use of numbers eg
rises to 10 / by 9 (dm3 per min)
or
increases up to 1.5 (min) / levels off after 1.5 (min) (of x axis timescale)
allow answer in range 1.4 to 1.5
or
after the first minute (of the run)
1
(iii)     supplies (more) oxygen
1
supplies (more) glucose
1
need ‘more/faster’ once only for full marks
allow removes (more) CO2 / lactic acid / heat as an alternative for either marking point one or two, once only
for (more) respiration
1
releases (more) energy (for muscle contraction)
do not allow energy production or for respiration
1
[9]
Q16.
(a)     (i)      diffusion
1
(ii)     carbon dioxide
accept CO2 / CO2
do not accept CO2
1
(iii)    red blood cells
1
(b)     70
if no / incorrect answer then
70 000 000
or
280 x 0.25 gains 1 mark
ignore doubling the answer
2
(c)     allows more gas / oxygen / CO2
(exchange)
do not accept air
1
[6]
Q17.
(a)

4 correct = 4 marks
3 correct = 3 marks
2 correct = 2 marks
1 correct = 1 mark
extra line from a structure cancels the mark
4
(b)     diffusion

Lesson 7
Q18  (a)     digested / broken down / made soluble by protease enzyme
in stomach in small intestine / from stomach / from pancreas
into amino acids
amino acids / small molecules absorbed into blood
any four for 1 mark each
4
(b)     ideas that
lipase / enzyme works best in alkaline / neutral conditions
acid denatures or inactivates enzyme / inhibits enzyme activity
bile emulsifies fat / bile produces larger surface area of fats / bile alkaline
for enzyme to work on / which increase activity of enzymes
any three for 1 mark each
3
[7]

Q19.
(a)     active transport
1
(b)     by transpiration stream / pull
1
in xylem
1
(c)     any three in the correct order from:
•        mount epidermis on a slide
•        count stomata in one area
•        repeat in four more areas
•        repeat method on other surface of leaf
•        calculate mean
allow nail varnish film
3
(d)     1
allow numbers written out in a line with middle number circled
1
(e)     (44 + 41 + 40 + 42 + 39) / 5 = 41.2
1
41
allow 41 with no working shown for 2 marks
1
allow 41.2 for 1 mark
(f)     less water lost
1
so it does not wilt
1
[11]

Lesson 8
Q20 (a)    LHS – carbon dioxide / CO2
allow CO2
ignore CO2
1
RHS
in either order
glucose / carbohydrate / sugar
allow starch
allow C6H12O6 / C6H12O6
ignore C6H12O6
1
oxygen
allow O2 / O2
ignore O2 / O
1

(b)     any five from:
•        factor 1: CO2 (concentration)
•        effect - as CO2 increases so does rate and then it levels off or shown in a graph
•        explanation:
(graph increases) because CO2 is the raw material or used in photosynthesis / converted to organic substance / named eg
or
(graph levels off) when another factor limits the rate.
accept points made via an annotated / labelled graph
•        factor 2: temperature
allow warmth / heat
•        effect – as temperature increases, so does the rate and then it decreases or shown in a graph
allow ‘it peaks’ for description of both phases
•        explanation:
(rise in temp) increases rate of chemical reactions / more kinetic energy
allow molecules move faster / more collisions
or
(decreases) because the enzyme is denatured.
context must be clear = high temperature
 
allow other factor plus effect plus explanation:
eg light wavelength / colour / pigments / chlorophyll / pH / minerals / ions / nutrients / size of leaves
2nd or 3rd mark can be gained from correct description and explanation
5
[8]

Q21 Q21.
(a)     6H2O
in the correct order
1
C6H12O6
1
(b)     (i)      control
do not accept ‘control variable’
allow:
to show the effect of the organisms
or
to allow comparison
or
to show the indicator doesn’t change on its own
1
(ii)     snail respires
1
releases CO2
1
(iii)    turns yellow
1
plant can't photosynthesise so CO2 not used up
1
but the snail (and plant) still respires so CO2 produced
1
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