Download BIOLOGY 4325-2H MARK SCHEME

BIOLOGY 4325-2H MARK SCHEME
Key
;
indicates separate mark points
/
indicates alternatives
eq
allow for correct equivalent
__
word underlined means no alternatives allowed
Question
Correct Answer
Number
1
Type of
Example
Multicellular
organism
plants
maize / eq;
YES
animals
human / eq; YES;
bacteria
Lactobacillus NO;
NO
viruses
influenza /
HIV / AIDS /
TMV / eq;
Acceptable Reject
Answers
Mark
(5)
(Total 5 marks)
Question
Number
2 (a)
Correct Answer
Acceptable Reject
Answers
Max 2
access / transport / travel /
communication;
trees for a purpose / construction /
manufacture / logging / eq;
trees for fuel;
farming / mining;
Question
Number
2 (b)
Correct Answer
(2)
Acceptable Reject
Answers
loss of habitat / food;
loss of numbers / death / extinction
/ loss of genes / migration / loss of
species / eq;
Mark
Mark
Max 4
less photosynthesis;
global warming / greenhouse effect /
ref to CO2 in air;
soil erosion idea / leaching;
flooding / eutrophication /
desertification / lack of minerals /
eq;
(4)
less transpiration;
less rainfall;
(Total 6 marks)
-104325 IGCSE Biology Summer 2008
Question
Number
3 (a)(i)
Correct Answer
Acceptable Reject
Answers
anther / stamen / pollen sac;
Mark
1
(1)
Question
Number
3 (a)(ii)
Question
Number
3 (a)(iii)
Correct Answer
Acceptable Reject
Answers
drawn to anther only (not to
filament);
Correct Answer
Mark
1
(1)
Acceptable Reject
Answers
Mark
2
pollen;
from anther/P to stigma;
(2)
Question
Number
3 (b)
Correct Answer
Question
Number
3 (c)(i)
Correct Answer
Question
Number
3 (c)(ii)
Acceptable Reject
Mark
Answers
sun /
phototropism 1
sunlight;
/ geotropism
(1)
light / gravity;
carbon dioxide + water; (or
opposite)
glucose + oxygen; (or opposite)
Ignore light / chlorophyll
Correct Answer
thin;
large surface area;
stomata;
air spaces / spongy (mesophyll);
Acceptable Reject
Answers
chemical
symbols;;
Mark
2
(2)
Acceptable Reject
Answers
pores /
guard
cells
Mark
Max 2
(2)
(Total 9 marks)
-114325 IGCSE Biology Summer 2008
Question
Number
4 (a)
Correct Answer
Acceptable Reject
Answers
Mark
Max 2
heart rate increases;
until 50 mins / 124;
then levels off / falls;
(2)
Question
Number
4 (b)
Correct Answer
Acceptable Reject
Answers
adrenaline;
Mark
1
(1)
Question
Number
4 (c)
Question
Number
4 (d)
Correct Answer
Acceptable Reject
Answers
2
higher heart rate / higher rate
sooner / eq;
nicotine / narrows arteries /
releases adrenaline / raises blood
pressure;
Correct Answer
Mark
(2)
Acceptable Reject
Answers
Mark
1
breathing / respiratory / nervous /
reproductive / digestive /
endocrine;
(1)
(Total 6 marks)
Question
Number
5
Correct Answer
Acceptable Reject
Answers
mouth / saliva;
mechanical digestion / chewing /
mastication / eq;
amylase; ONCE Ignore carbohydrase
(starch to) maltose;
pancreas / pancreatic juice / eq;
small intestine / duodenum / ileum;
starch/maltose to glucose;
maltase;
Mark
Max 6
(6)
(Total 6 marks)
-124325 IGCSE Biology Summer 2008
Question
Number
6
Correct Answer
Acceptable Reject
Answers
Mark
8
vena cava;
atrium / auricle;
lung;
valves;
aorta;
hepatic;
glucose / sugar;
glycogen;
(8)
(Total 8 marks)
Question
Number
7 (a)
Correct Answer
Step
Order of
step
repeat crosses for
several generations
4
2 correct =
2;;
cross parent plants to
produce more offspring
2
1 correct =
1;
identify parent plants
with desired
characteristics
Mark
Max 3
1
select offspring with
desired characteristics
Question
Number
7 (b)
Acceptable Reject
Answers
all 4 = 3;;;
3
Correct Answer
(3)
Acceptable Reject
Answers
large numbers;
quickly produced;
identical / all have desired
characteristic / cloned / eq;
Mark
Max 2
(2)
(Total 5 marks)
-134325 IGCSE Biology Summer 2008
Question
Number
8 (a)
Correct Answer
Acceptable Reject
Answers
Mg;
magnesium;
Mark
1
(1)
Question
Number
8 (b)
Correct Answer
3.6 / 5.4 x 100 = 66.7;; Accept
66.67 / 66.6666etc
one for 3.6
Acceptable Reject
Answers
66 and two
thirds;
Mark
2
(2)
Question
Number
8 (c)
Correct Answer
all / extra / increase / more
mineral ions / more named mineral
/ correct amount / eq;
Acceptable Reject
Answers
nutrients
Mark
2
(2)
use or purpose;
(Total 5 marks)
Question
Number
9 (a)(i)
Question
Number
9 (a)(ii)
Correct Answer
Acceptable Reject
Answers
2
X = cell body / nucleus / eq;
Y = myelin /sheath / fat / fatty
sheath /
axon / cell membrane /
Schwann cell;
Correct Answer
Mark
(2)
Acceptable Reject
Answers
B / sensory / eq;
Mark
1
(1)
Question
Number
9 (a)(iii)
Correct Answer
Acceptable Reject
Answers
A / relay / eq;
Mark
1
(1)
Question
Number
9 (b)(i)
Correct Answer
Acceptable Reject
Answers
axis correct;
axes labelled speed and diameter;
Mark
2
(2)
-144325 IGCSE Biology Summer 2008
Question
Number
9 (b)(ii)
Question
Number
9 (b)(iii)
Correct Answer
Acceptable
Reject
Answers
proportional;
as diameter increases speed of
impulse increases / linear /
proportional / eq;
Mark
1
(1)
Correct Answer
Acceptable Reject
Answers
34 /read from graph;
Mark
1
(1)
(Total 8 marks)
Question
Number
10 (a)(i)
Correct Answer
Acceptable Reject
Answers
Dd and Dd;
DD, Dd, Dd, and dd; (any order)
Mark
2
(2)
Question
Number
10 (a)(ii)
Question
Number
10 (a)(iii)
Question
Number
10 (b)
Question
Number
10 (c)
Correct Answer
Acceptable Reject
Answers
3:1 / 75:25 / 75% to 25% / 3
quarters to 1 quarter / eq;
Mark
1
Correct Answer
Acceptable Reject
Answers
Mark
2
zero;
both parents must be DD / dd
parents are sterile / neither parent
has d/recessive allele;
Ignore term gene
Correct Answer
(1)
(2)
Acceptable Reject
Answers
bigger surface area to volume ratio;
lack insulation/fat;
lose (more) heat;
maintain body temperature;
respiration;
Correct Answer
Mark
Max 2
(2)
Acceptable Reject Mark
Answers
Hormone
Endocrine
gland
Target
organ
Effect
(adrenaline)
(adrenal)
(heart)
(oestrogen)
ovary;
uterus
/
womb;
increase
rate /
eq;
(repair
lining)
(3)
(Total 10 marks)
-154325 IGCSE Biology Summer 2008
Question
Number
11 (a)
Question
Number
11 (b)(i)
Question
Number
11 (b)(ii)
Correct Answer
glucose / C6H12O6;
carbon dioxide/CO2 +
ethanol/alcohol/ C2H5OH;
Ignore energy
Correct Answer
Acceptable Reject
Answers
chemical
symbols
Acceptable Reject
Answers
gene / DNA / allele (for enzyme);
cut;
restriction / endonuclease;
plasmid / vector / gene gun / phage /
ligase;
gene / DNA / allele into yeast;
Correct Answer
Mark
2
(2)
Mark
Max 4
(4)
Acceptable Reject
Answers
enzyme / amylase;
digests starch / less starch / starch
to sugar;
Mark
2
(2)
(Total 8 marks)
Question
Number
12
Correct Answer
Acceptable
Answers
Process
decomposition
transpiration
nitrification
Reject
Mark
Description
bacteria / microorganisms /
fungi / saprobionts / eq;
breakdown/digest dead
organisms / organic matter /
waste / eq;
evaporation / diffusion / loss of
water;
from plant / leaf / stomata;
bacteria / named bacteria;
ammonia/ammonium (cpds) to
nitrite/nitrate / nitrite to
nitrate;
vasodilation
widening / eq; I dilation
blood vessels / arteries /
arterioles; I capillaries
(8)
veins
(Total 8 marks)
-164325 IGCSE Biology Summer 2008
Question
Number
13 (a)(i)
Question
Number
13 (a)(ii)
Correct Answer
energy / insulation / cell
membranes / neurones / growth /
making new cells /eq;
Correct Answer
Acceptable Reject
Answers
keep warm
/ eq
Acceptable Reject
Answers
bones / teeth / skeleton;
Mark
1
(1)
Mark
1
(1)
Question
Number
13 (b)
Question
Number
13 (c)
Correct Answer
Acceptable Reject
Answers
Max 2
respiration / heat / excretion /
egestion / movement / uneaten /
indigestible;;
Correct Answer
(2)
Acceptable Reject
Answers
nitrates / mineral ion(s) / named
mineral ion(s) / eq;
growth of plants / algal bloom;
eutrophication;
light blocked / less photosynthesis;
death of organisms (plant/fish);
bacteria / microorganisms / eq;
oxygen depletion /eq;
respiration;
Mark
Mark
Max 5
(5)
(Total 9 marks)
-174325 IGCSE Biology Summer 2008
Question
Number
14 (a)
Correct Answer
Person
Question
Number
14 (b)
Question
Number
14 (c)(i)
Question
Number
14 (c)(ii)
A
BMI
value
(24.2)
B
C
29.6
39.6;
Description
of weight
(normal
weight)
overweight
obese;
Correct Answer
Acceptable Reject
Answers
TE for
wrong BMI
but
correct
description
=1
(2)
Acceptable Reject
Answers
higher / greater / increase / eq;
Correct Answer
more risk for men up to 28 /
similar risk up to 28 / eq;
more risk for women (than men)
above 28;
more risk for men and women
above 28;
more risk as BMI increases;
Mark
Mark
1
Acceptable
Reject
Answers
allow higher
BMI/overweight
as eq to 28
Correct Answer
Acceptable Reject
Answers
coronary artery;
fat/cholesterol blocks/deposits;
(aerobic to) anaerobic;
(1)
Mark
2
(2)
Mark
Max 5
(less) oxygen;
(less) glucose;
less respiration / less energy / ATP;
lactic acid;
builds up / toxic / inhibit enzymes /
eq;
(5)
(Total 10 marks)
-184325 IGCSE Biology Summer 2008
Question
Number
15 (a)
Correct Answer
location; (Bowman’s capsule /
glomerulus)
Acceptable Reject
Answers
converse
Mark
Max 3
pressure used;
no energy/ATP required / no active
transport;
molecules out of blood / into
nephron / eq;
(3)
depends on molecule size / eq;
hormones not involved;
Question
Number
15 (b)(i)
Correct Answer
Event
after
doing lots
of
exercise
after
eating lots
of protein
after
drinking
lots of
water
after
eating
salty
crisps
Question
Number
15 (b)(ii)
Volume
of urine
(large or
small)
small;
Acceptable Reject
Answers
Mark
Concentration
of urine
(dilute or
concentrated)
(concentrated)
(small)
concentrated;
large
dilute;
small
concentrated;
(4)
Correct Answer
(less) water reabsorbed;
collecting duct;
ref permeability;
more loss of water / more water in
urine / more urine / dilute urine /
dehydration / blood concentration
increases;
-194325 IGCSE Biology Summer 2008
Acceptable Reject
Answers
ADH story
in
converse
Mark
4
(4)
Question
Number
15 (c)(i)
Question
Number
15 (c)(ii)
Correct Answer
less pressure / flow speed;
larger lumen / eq;
closer to surface / easier to see /
eq;
thinner wall / easier to penetrate;
Correct Answer
Acceptable Reject
Answers
converse
Mark
Max 2
(2)
Acceptable Reject
Answers
Mark
2
diffusion;
high conc. to low conc. /
conc.gradient;
(2)
Question
Number
15 (c)(iii)
Correct Answer
Acceptable Reject
Answers
toxins /
hormones
/ glucose
/ lactic
acid
urea;
carbon dioxide;
water;
Mark
Max 2
(2)
(Total 17 marks)
PAPER TOTAL 120 MARKS
-204325 IGCSE Biology Summer 2008
BIOLOGY 4325-03 MARK SCHEME
Key
;
/
eq
__
indicates separate mark points
indicates alternatives
allow for correct equivalent
word underlined means no alternatives allowed
Question
Number
1
Correct Answer
Acceptable Reject
Answers
Benedict’s; and bunsen; (or
opposite)
iodine; and spotting tile; (or
opposite)
Mark
(4)
(Total 4 marks)
Question
Number
2 (a)
Question
Number
2 (b)
Correct Answer
Acceptable Reject
Answers
increases;
30 oC / fastest at 30 oC / optimum;
decreases / slows down / stops;
Correct Answer
Max 2
(2)
Acceptable Reject
Answers
ref. movement of molecules /
(kinetic) energy;
more/faster collisions;
optimum;
denature / destroy enzyme/active
site;
Mark
Mark
Max 3
(3)
(Total 5 marks)
-214325 IGCSE Biology Summer 2008
Question
Number
3 (a)(i)
Question
Number
3 (a)(ii)
Correct Answer
(3)
14;
Acceptable Reject
Answers
11;
Correct Answer
Mark
(2)
Acceptable Reject
Answers
Mark
scale linear + minimum of half axis;
plot;;
axis - number + plants 1, 2 and 3;
key – smooth and wrinkled;
(5)
Question
Number
3 (b)
Correct Answer
Acceptable Reject
Answers
Mark
Max 3
smooth dominant / wrinkled
recessive;
parent plants are heterozygous / Ss
and Ss / carriers;
genotype of offspring SS Ss Ss and
ss;
phenotypes correct / 3:1 / 1 in 4 /
25% / eq;
(3)
(Total 10 marks)
Question
Number
4 (a)(i)
Correct Answer
Acceptable Reject
Answers
use ruler / graph paper / eq;
qualified – use as template / cut all
together / line up together / use
straight edge / set square / method
to ensure cut is perpendicular / eq;
Question
Number
4 (a)(ii)
Mark
Correct Answer
(2)
Acceptable Reject
Answers
Mark
temperature / volume of solution /
light / eq;
incubator / measuring cylinder /
keep in dark / eq;
(2)
same potato = max 1
-224325 IGCSE Biology Summer 2008
Question
Number
4 (b)(i)
Correct Answer
Acceptable Reject
Answers
9.6 9.7 9.7; (any order)
(3 correct = 2 marks, 2 or 1
correct = 1 mark)
Question
Number
4 (b)(ii)
Question
Number
4 (b)(iii)
Mark
Correct Answer
(2)
Acceptable Reject
Answers
-0.4 -0.3 -0.3; (from student answer)
allow transfer error
Correct Answer
Mark
(1)
Acceptable Reject
Answers
Mark
water out (of potato);
osmosis;
dilute solution to stronger solution /
eq;
(3)
Question
Number
4 (c)
Correct Answer
Acceptable Reject
Answers
Mark
increase in length;
water enters (potato);
(2)
Question
Number
4 (d)(i)
Question
Number
4 (d)(ii)
Correct Answer
Acceptable Reject
Answers
repeat / use more cylinders / use
more potatoes;
Correct Answer
Mark
(1)
Acceptable Reject
Answers
weigh potato / measure in
mm/decimal places / use vernier
callipers / eq;
Mark
(1)
(Total 14 marks)
Question
Number
5 (a)
Question
Number
5 (b)
Correct Answer
Acceptable Reject
Answers
(top/chemical/mass/digital) balance
/ scales / any weighing machine / eq;
Correct Answer
Mark
(1)
Acceptable Reject
Answers
Mark
reliability / average / less chance of
anomalous/rogue result affecting
average / eq;
(1)
-234325 IGCSE Biology Summer 2008
Question
Number
5 (c)
Correct Answer
Acceptable Reject
Answers
Mark
Max 4
light;
use bulb / same time of day / eq;
wind / air speed;
shelter from drafts / use fan / eq;
humidity / eq;
dry room / enclose in plastic bag /
silica gel / eq;
(4)
leaves of same species / type / age;
same plant /eq;
Ignore temperature / size of leaf
Question
Number
5 (d)
Correct Answer
Acceptable Reject
Answers
Mark
mass loss reduces /eq;
(less) evaporation / diffusion /
transpiration / molecular movement
/ eq;
(2)
Reject photosynthesis
Question
Number
5 (e)
Correct Answer
Acceptable Reject
Answers
Mark
cover idea;
vaseline / petroleum jelly / use of
cobalt chloride / eq;
US / LS;
(3)
(Total 11 marks)
-244325 IGCSE Biology Summer 2008
Question
Number
6
Correct Answer
C
eq;
Acceptable Reject
Answers
Mark
two / several temperatures /
O
same person / mass / gender
/ body
fat / age / fitness /
eq;
R
repeat / eq;
M
1 how collected / eq;
2 ref to time;
S 1 + 2level of exercise / clothing /
humidity / time of day / eq;;
(6)
(Total 6 marks)
PAPER TOTAL 50 MARKS
-254325 IGCSE Biology Summer 2008
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