biology

1 the diagram shows an eyepiece graticule and cell viewed through a microscope. when the
eyepiece graticule was calibrated at this magnification, the whole length of the graticule shown
covered 12 divisions of a stage micrometer scale.

there were 100 divisions in 10mm of the stage micrometer.
what is the actual length of the cell?
a 2.5um b 3.6um c 360um d 3mm

2 which cell structures can form vesicles?
cell structure

cell surface endoplasmic golgi body

membrane reticulum
a v v ra key
b v v x / = can form vesicles
cc v x v x = cannot form vesicles
d x jv v

3 the diagram shows three circles, 1, 3 and 5, representing chloroplasts, mitochondria and typical
prokaryotes.
circle 3
circle coo ys 5

which row correctly identifies the three circles and some of the structures that are shared
between them?
[weet [eases [ase]

a chloroplasts circular dna mitochondria | 80s ribosomes prokaryotes

b chloroplasts | 80s ribosomes | mitochondria circular dna prokaryotes

cc prokaryotes circular dna mitochondria circular dna chloroplasts

d prokaryotes 70s ribosomes | chloroplasts | 80s ribosomes | mitochondria

4 which cell structures contain rna?

1 centrioles
2 mitochondria
3 nucleus
4 ribosomes

a 1,2,3and4

b- 1and 2 only

c 2,3 and 4 only

d 3and4 only

5 it is possible for a bacterium to synthesise a eukaryotic protein.
this involves introducing a eukaryotic gene into the bacterial dna. the eukaryotic gene is then
translated by the bacterium.
what explains why a bacterial cell can produce a eukaryotic protein but cannot produce a
eukaryotic glycoprotein?
a bacteria do not have rough endoplasmic reticulum.
b_ bacteria do not have a nuclear envelope.
c_ bacteria do not have mitochondria.
d_ bacteria do not have golgi bodies.

6 which structures are found in typical prokaryotic cells and also in typical plant cells?
a cell walls
b _shistones
c_ telomeres
d__tonoplasts

7 the molecule shown is a polymer of reducing sugars.
ch,oh ch,oh ch,oh ch,oh
(8) (@) [e) 1)
oh o oh 0 oh o oh
ho oh
oh oh oh oh
which procedures could be carried out to show that this molecule is a polymer of reducing
sugars?
1 add hydrolytic enzyme and then heat with benedict’s solution.
2 dissolve in water, neutralise and then heat with benedict’s solution.
3 boil with hydrochloric acid, neutralise and then heat with benedict’s solution.
a 1,2and3 b jiand2only c tand3only d 2and3only

8 which statement about biological molecules is correct?
a amylopectin, amylose and cellulose are all polymers.
b amylose, cellulose and glucose are all macromolecules.
c_ cellulose, glucose and starch are all monomers.
d_ sucrose, starch and amylopectin are all polysaccharides.

9 sugars with a ring structure can also have a linear structure.
h
bo
h tion
hob
h boon
h — boon
lon
which of these sugar molecules could be represented by the linear structure in the diagram?
1 glucose
2 ribose
3 sucrose
a i1and2 b 2and3 c 1only d = 2only

10 which statements about phospholipids and triglycerides are correct?
1 they both contain ester bonds.
2 they both have three fatty acid chains per molecule.
3 they both may have saturated and unsaturated fatty acid chains.
4 they are both used only as storage molecules.
a 1,2and3 b 1 and 3 only c 2,3and4 d 2and4 only

11 the diagrams show three examples of different bonds.
bond 1 o bond 2 bond 3
5 a =ct u — —ch _sts—cn —
nh o=c cc i 2 2
h
which bonds hold the secondary structure of proteins together?
a 1,2and3
b 1and 2 only
c 1only
d 2and3 only

12 hydrogen bonding explains many of the properties of water, including the high latent heat of
vapourisation and high specific heat capacity.
for which processes in plants is hydrogen bonding in water important on hot sunny days?
1 preventing denaturation of enzymes in leaves
2 reducing water loss by evaporation
3. allowing leaves to cool down quickly at night
4 holding the column of water in xylem vessels together
a 1,2,3and4
b 1,2 and 4 only
c 1,3 and 4 only
d 2and 3 only

13 what is the most appropriate set of controls to use in an investigation into the rate of an
enzyme-catalysed reaction over a range of temperatures from 25°c to 65°c?
a enzyme and substrate at all temperatures tested
b enzyme and boiled substrate at all temperatures tested
c boiled enzyme only at all temperatures tested
d substrate only at all temperatures tested

14 an investigation is carried out with an enzyme at its optimum temperature and ph.
the rate of the enzyme reaction is measured at different substrate concentrations.
the investigation is repeated in the presence of a competitive inhibitor.

how will the results with the competitive inhibitor be different from the original results?
inhibitor inhibitor
a higher lower
b higher the same
cc the same lower
d the same the same

15 which description of cell surface membrane permeability is correct?

a_ an increase in the concentration of cholesterol molecules in the cell surface membrane can
increase its permeability to hydrophilic substances.

b_ cell surface membrane permeability to large hydrophilic molecules is high and can be
increased by membrane transport proteins involved in facilitated diffusion.

c the permeability of the cell surface membrane to ions increases as the proportion of
saturated fatty acid chains in the phospholipids increases.

d_ without the presence of carrier and channel membrane proteins, the cell surface membrane
has a low permeability to large polar molecules.

16 which transport mechanism within a cell can occur in the absence of membranes?
a active transport
b_ diffusion
c facilitated diffusion
d_ osmosis

17 a student measured the time taken for complete diffusion of a dye into agar blocks of different
sizes.
the results are shown in the table.
/mmxmmxmm diffusion/s
5oebixd 6.2
10x 10x10 16.1
15x15x15 34.5
5% 10«15
what is the predicted time for complete diffusion of the dye into the agar block measuring
5mm x 10mm x 15mm?
a 62s
b 16.1s
c 345s
d- more than 34.5s

18 a plant cell with a water potential of -600 kpa was placed in a solution with a water potential of
—410 kpa for 10 minutes.
which row is correct?
net movement water potential
effect on cell
of water of cell

a into cell becomes higher becomes turgid

b into cell becomes lower bursts

cc out of cell becomes higher swells

d out of cell becomes lower becomes plasmolysed

19 which cells contain telomeres that are longer than those in a helper t-lymphocyte secreting
cytokines?
1 bone marrow stem cells
2 mature red blood cells
3 activated memory b-lymphocytes
a iand2 b 1and3 c 2only d = 3only

20 in which stage of the cell cycle are telomeres needed to prevent the loss of genes?
a prophase
b_ cytokinesis
c gr, phase
d sphase

21 which row shows part of the correct sequence of mitosis?
a chromosomes nuclear 1 ‘
chromosomes 5 lineup atthe —> envelope = spindle fibres
condense : shorten
equator disappears
b chromosomes ; ' nuclear
line up atthe > spindle fibres - chromosomes = envelope
shorten condense
equator reappears
c chromosomes : g nuclear
; spindle fibres chromosomes
line up atthe —> => envelope => ;
shorten uncoil
equator reappears
d nuclear . ’ chromosomes
chromosomes spindle fibres :
: = envelope > — line up at the
uncoil : shorten
disappears equator

22 what is correct for cytosine?
: , joins to its
has a single ring ’ er
structure is a pyrimidine complementary base
with 3 hydrogen bonds

a v v v key
b v x v / = correct
cc x v x x = incorrect
d x x v

23 scientists grew bacteria in a medium containing heavy nitrogen, °n, as the only source of
nitrogen. after many generations, both strands of all of the bacterial dna molecules contained
heavy nitrogen.

these bacteria were then moved from the heavy nitrogen medium into a medium with only light
nitrogen, ‘4n). the bacteria divided once to form the first generation and once more to form the
second generation.
a sample of bacteria was collected from the second generation and the dna was analysed to
find:
e the percentage of dna strands that contained only light nitrogen
e the percentage of dna molecules that contained light nitrogen and heavy nitrogen.
which row shows the results of this analysis?
percentage of dna strands percentage of dna molecules
that contained only light that contained light nitrogen
nitrogen and heavy nitrogen
a 50 25
b 50 50
cc 75 25
d 75 50

24 the table shows the trna anticodons for four amino acids.
asparagine uuva, uug
glutamic acid cuu, cuc
proline gga, ggg, ggu, ggc
threonine uga, ugg, ugu, ugc
a cell makes a polypeptide containing the amino acid sequence shown.
asparagine — threonine — proline — glutamic acid
which sequence of bases on the transcribed strand of a dna molecule could code for this part of
the polypeptide?
a aatacccctgaa
b aatacccctcaa
c ttacttggatgg
d ttatggggactt

25 the photomicrograph shows a section of a plant organ.
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peel see: ses ng peers ters
goo oy ee ees),
bie colon a wet op old mere © a0. |
\ waar au neva eee oo rae: 0% sos
pas \ por ty vana ca td ¢ i se sess:
4 ae ne oo ae :
psu ace -oyer
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\ 4 pa vas va nan see
cos a oa ose 5
l\ yt we van see ete a be
ea yn yoy ned rco a oe
students were asked to study the photomicrograph and identify the organ, giving a reason to
support their answer.
which statement written by the students correctly identifies the organ and provides a correct
reason to support this identification?
a_itis aleaf because the xylem is located on the inner side of each vascular bundle.
b_ it is a stem because there is a ring of endodermis visible around the edge of the vascular
tissue.
c_itis a stem because the vascular bundles are arranged in a ring near the epidermis.
d_itis a xerophytic leaf because there is a thick epidermis made up of many layers of cells.
a a a

26 vvhat is correct about the apoplastic pathway and symplastic pathway in a root?
| | apoplastic pathway symplastic pathway
a casparian strip blocks water moves across the
the movement of water root through cell walls
b water moves across the water moves from cell to
root through cell walls cell via the plasmodesmata
cc water moves from cell to water passes through
cell via the plasmodesmata the cytoplasm
d water passes through casparian strip blocks
the cytoplasm the movement of water

27 sucrose moves into a phloem sieve tube element from a leaf mesophyll cell.
which changes to the water potential and the volume of solution in the phloem sieve tube
element are correct?
water potential volume of
becomes solution
a higher decreases
b higher increases
cc lower decreases
d lower increases

28 the photomicrograph shows three white blood cells labelled x, y and z.
.
bs *
.—_ @
which row correctly identifies these cells?
[ex [ay | iz]
a lymphocyte monocyte neutrophil
b lymphocyte neutrophil monocyte
cc monocyte neutrophil lymphocyte
d neutrophil monocyte lymphocyte

29 which row correctly identifies the locations in which a type of molecule or cell is present?
|_| type of molecule or cell lymph pony
a antibody jv jv jv key
b large plasma protein v x v jv = present
cc lymphocyte v jv x x =not present
d phagocyte x v v

30 the graph shows the changes in pressure that occur in the left side of the heart during one
cardiac cycle.
an
y \
| \
i
| \
\
i \ k
pressure | \ ey
i \ ———-—-— left ventricle
i \
| 1 —— aorta
' / seesceeees-+ left atrium
| \
gee. eee,
0 pos 4, od a
0 0.2 0.4 0.6 0.8
time/s
at which time are the semi-lunar valves in the heart open?
a 0.1s b 03s c 05s d 07s

31 what would change the ratio of red blood cells to white blood cells in the blood of a healthy
human?
1 development of leukaemia
2 __ infection with variola
3 __ living for six months at high altitude
a 1,2and3 b 1and2only c 1and3only d = 2and3only

32 the diagram represents three types of cell found in the human gas exchange system.
x ¥ zz
which of these cell types could be affected when a person is exposed to tar in cigarette smoke?
a x,yandz b xandzonly c yandzonly d yonly

33 the photomicrograph shows part of the lung as seen using a light microscope.
2
5 &, ays
"3 “ 7 psy .
aw ee: tly ze i f ne. ay * a
ec sd
aa. ee vg fe ag fe é
e 5 yon i ee ee
ete tga a ‘
bacay apy 5 bg een) 8 :
“sie ae 3 ae .
ome . ie
1 9 ioe can earners 7)
dere tns ns ss pe fooling
bjee ge ae gf |
gp he bone ue ; “7s ;
wee ¥. <a whe, i
pa aes be teez y
which row correctly identifies the features labelled 1, 2 and 3?
a ee
a alveolus capillary bronchiole
b alveolus bronchiole capillary
c bronchiole small artery alveolus
d small artery bronchiole alveolus

34 how many times must a molecule of oxygen pass through a cell surface membrane as it diffuses
from inside an alveolus, through a cell in the capillary wall, to bind to a molecule of haemoglobin?
a 3 b 4 cc 5 d 10

35 a disease is an abnormal disruption to the functioning of an organism or part of an organism.
which disruption to function is an example of an infectious disease?
a airflow to one lung is disrupted by uncontrolled cell division forming a mass of cells.
b_ airways become inflamed due to exposure to smoke.
c oxygen transport is disrupted due to changes in protein shape in red blood cells.
d lung tissue is disrupted by the multiplication of prokaryotic cells.

36 the number of people at risk of contracting malaria has increased due to an increase in the
distribution of anopheles mosquitoes.
what could be the cause of this increase in the distribution of anopheles mosquitoes?
a antibiotic resistance
b_ drug resistance in plasmodium
c_ no effective vaccine
d_ global warming

37 which diseases are treated with antibiotics?
cholera
/ ~

38 which row correctly describes b-lymphocytes?
: release antibodies
processedin | . .
immediately after
the thymus :
formation
a jv v key
b v x v¥ =correct
cc x v x = incorrect
d x x

39 which features of monoclonal antibodies are important to their use in the treatment of cancer?
1 they can bind to tumour-associated antigens.
2 they can distinguish between different strains of pathogens.
3 they can deliver drugs to specific targets.
poa a 8

a v v x key

b v x v v¥ = is important

cc x v v x = is not important

d j x x

40 a student was asked to explain why vaccination has successfully eradicated smallpox but not
other diseases, such as measles, malaria and sickle cell anaemia. these are the statements
made by the student.

1 the antigens of the virus causing smallpox did not change, unlike the antigens of
the virus causing measles.
2 sickle cell anaemia has many different types of mutation, unlike smallpox, so each
would require a vaccine.
3. unlike smallpox, malaria involves animals as part of the transmission cycle and this
makes the cycle harder to break.
4 the vaccine against measles often causes a poor primary immune response so that
booster vaccines are required, unlike the vaccine against smallpox.
which statements are possible explanations?
a 1,3 and4 b iand2 c 1and4 only d 2and4

Solve 9700_m20_qp_12