biology

1. the electron micrograph shows onion root cells prepared using a freeze-fracture technique. the
cells were quickly frozen and then physically broken apart. freeze fracture breaks apart cells
along weak areas, such as membranes and the surfaces of organelles.

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of. ae og ee e structure x

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pe na 8 ge eae oe

x20 000

which statement best explains the appearance of the electron micrograph?
a_ the cells were broken apart at the endoplasmic reticulum; structure x is a ribosome.
b_ the cells were broken apart at the nuclear envelope; structure x is a nuclear pore.
c_ the cells were broken apart at the nuclear envelope; structure x is a ribosome.
d_ the cells were broken apart at the tonoplast; structure x is a plasmodesma.

2 which cell structures can form vesicles?
foo
membrane reticulum
a v jv v key
b v v x / = can form vesicles
cc v x v x = cannot form vesicles
d x v v

3 four students were asked to match the function with the appearance of some cell structures in an
animal cell.
the functions were listed by number.
1 synthesis of polypeptides
2 _ synthesis of lipids
3. packaging of hydrolytic enzymes that will remain in the cell
the appearances were listed by letter.
vs membranes which surround an enclosed inner cavity
w_non-membrane-bound, spherical structures
x adouble membrane interspersed with pores
y —non-membrane-bound, cylindrical structures
z membrane-bound sacs, arranged as a flattened stack
which student correctly matched the numbered function with the appearance of the cell
structure?
pop te
a www vv z
b www z y
cc z www z
d z. vv www

4 which cells contain a tonoplast?
me ane sa [ee
a v v v v key
b v x v jv ¥ = contain tonoplast
cc x v v x x = do not contain tonoplast
d v v x jv

5 which organelles found in animal or plant cells are surrounded by double membranes?
a_ chloroplasts, mitochondria, vacuoles
b_ chloroplasts, mitochondria, nuclei
c_ chloroplasts, nuclei, vacuoles
d_ mitochondria, nuclei, vacuoles

6 some scientists think that mitochondria evolved from bacteria that entered the cytoplasm of a
different cell and were able to survive there.
which structural features of mitochondria support this hypothesis?
a li ncctalgs circular dna | 70s ribosomes
membrane
a jv v v key
b v v x /¥ = supports
cc v x v x = does not support
d x v v

7  whatis present in all viruses, all prokaryotes and all eukaryotes?
a_ ribose
b_ deoxyribose
c_ cytosine
d_ thymine

8 the table shows some steps that can be made in carrying out the benedict's test.
which combination of steps is required to carry out a semi-quantitative test on a reducing sugar
solution?
standardise boiling
standardise volume boil with time with benedict's
of benedict’s hydrochloric acid solution and
solution and volume | and then neutralise | compare final colour
of test solution with alkali with numbered
colour standards
a v x x key
b x v x v= step made
cc v x v x = step not made
d x x v

9 the diagrams show three examples of different bonds.
bond 1 0 bond 2 bond 3
suinane la a
h
which bonds hold the secondary structure of proteins together?
a 1,2and3 b 1and3only c = 1only d 2and 3 only

10 insulin is a globular protein involved in cell signalling. it is transported in the blood plasma from
the cells that synthesise it to its target cells. a molecule of insulin contains six sulfur-containing
amino acids and has two polypeptide chains.

which statements about insulin are correct?
1 aninsulin molecule has a quaternary structure.
2 insulin polypeptides are held together by six disulfide bonds.
3 amino acids with hydrophobic r groups would be found in the centre of an insulin
molecule.
a 1,2and3 b 1dand2only c t1and3only d = 2and3only

11. which statement correctly explains why blood plasma can be maintained at a_ stable
temperature?
a ithas a low specific heat capacity.
b_ it has a high specific heat capacity.
c_ithas a low latent heat of vaporisation.
d_ithas a high latent heat of vaporisation.

12 which region on the graph shows the activation energy of an enzyme-catalysed reaction?
+a
bp

energy of —_— wo--------f-----4----

molecules

in a reaction

without d
with enzyme enzyme
time

13 the graph shows the effect of an increasing substrate concentration on the rate of an
enzyme-catalysed reaction.
maximum rate of reaction
rate of po
reaction p pog
77 q
ae
oe
ca
‘a
substrate concentration

line p represents the result when the enzyme is used at its optimum ph and optimum
temperature and without an inhibitor.
line q represents the result when the reaction conditions are changed.
which descriptions of changes to the reaction conditions could result in line q if all other
conditions were kept the same?

1 add an inhibitor that attaches to a site other than the active site.

2 add an inhibitor that has a similar shape to the substrate.

3. add an inhibitor that blocks the active site of the enzyme.

4 carry out the reaction at a higher temperature.
a 1,3 and4 b- 1and 4 only c 2,3and4 d 2and 3 only

14 which statement about cell signalling is correct?
a one type of receptor molecule will recognise all ligands in the body.
b_ the binding of a ligand may cause a change to the shape of the receptor.
c_ the receptors for ligands are always found on the inside of cells.
d_ the same ligand is made by all of the cells in the body.

15 four students, a, b, c and d, observed plant epidermal cells that had been placed in a
concentrated sucrose solution for 30 minutes. they were asked to identify the partially permeable
layer and to explain the appearance of the cells in terms of water potential and movement of
water.

which student is correct?
partially water potential movement of water
permeable layer at start of experiment during experiment
a cell surface cell contents have a lower water moved out of the cell
membrane water potential than the and no water moved in
sucrose solution
b cell surface cell contents have a higher more water moved out
membrane water potential than the of the cell than moved in
sucrose solution
cc cell wall cell contents have a lower more water moved out
water potential than the of the cell than moved in
sucrose solution
d cell wall cell contents have a higher | water moved out of the cell
water potential than the and no water moved in
sucrose solution

16 the table compares the surface area to volume ratios of five agar blocks that differ in dimensions
but which all have the same volume.
the agar blocks can be used to measure the efficiency of diffusion, where efficiency is measured
as the time taken for a dye to reach all parts of the block.
[sae [ome [a [sc [a [a
/mm /mm /mm area/mm? /mm* volume ratio

1 8 8 8 384 512 0.75

2 16 16 2 640 512 yies}

3 32 4 4 544 512 a

4 32 32 0.5 2112 512 4.1

5 64 4 2 784 512 1.5
which prediction can be made about the way in which size and dimensions of these blocks affect
the efficiency of diffusion?
a_ the efficiency of diffusion will decrease as the width of a block increases.
b_ the efficiency of diffusion will increase as the height of a block increases.
c_ the efficiency of diffusion will increase as a block of fixed volume is flattened.
d_ the efficiency of diffusion will decrease as a block of fixed volume is elongated.

17 the cell cycle includes mitosis.
what are features of this type of nuclear division?
1 forms cells of equal size to the parent cell
2 forms genetically identical nuclei
3. semi-conservative replication of dna
a 1,2and3 b 1tand2only c 1and3only d 2only

18 a student observed the cells in the growing region (meristem) of an onion root and obtained the
data shown.
of cells
interphase 886
prophase 73
metaphase 16
anaphase 14
telophase 11
which percentage of cells contains chromosomes that appear as two chromatids?
a 7.3% b 8.9% c 95.9% d 97.5%

19 which statement about messenger rna is correct?
a in eukaryotic cells, mrna is made by removing exons from the primary rna transcript.
b  mrnais a single-stranded polynucleotide containing a different purine base than dna.
c mrna molecules contain ribose sugars joined to phosphate groups by phosphodiester
bonds.
d je monomers of mrna contain a phosphate group, deoxyribose sugar and a nitrogenous
ase.

20 which structures are involved in transcription only?
dna template ’ rna
anticodons
strand polymerase

a v v x key

b v x v ¥ = involved

cc x v x x = not involved

d x x v

21 one gene provides the code for the production of which type of molecule?
a amino acid
b dna
c nucleotide
d polypeptide

22 the table shows some mrna codons that code for certain amino acids.
gcg, gca, gcc, gcu alanine
acg, aca, acc, acu threonine
ugc, ugu cysteine
uac, uau tyrosine
cag, caa glutamine
cgg, cga, cgc, cgu arginine
a dna template strand has the base sequence shown.
acagtattatttgcaacg
what would the change in the amino acid be if the first base in the fifth dna triplet was
substituted for an a base?
a alanine to cysteine
b alanine to threonine
c arginine to cysteine
d arginine to threonine

23 which structures contain cytoplasm with mitochondria and a nucleus?
xylem vessel element
companion ln phloem
cell sieve tube
element

24 what is the correct term to describe intermolecular hydrogen bonding between water molecules?
a_ adhesion
b_ cohesion
c osmosis
d diffusion

25 the diagram shows the outline of a xerophytic leaf that had been left for 45 minutes in different
conditions, p and q.
¥
7 (u)
p q
which statements about the cells in layer y of the leaf in each of the conditions p and q after
45 minutes are correct?
1 there is a less negative water potential in p than in q.
2 the cells may be turgid in p and plasmolysed in q.
3. the cells are less turgid in p than in q.
4 there is no net diffusion of water into y in either p or q.
a 1,2and4 b 1,3and4 c 1 and 3 only d 2and4 only

26 how does sucrose move from chloroplasts to the phloem?
1 diffusion
2  apoplast pathway
3 symplast pathway
a 1,2and3 b tand2only c t1and3only d 2and3only

27 how are companion cells involved in loading sucrose into phloem sieve tube elements?
a actively through cotransporter proteins and passively through plasmodesmata
b actively through cotransporter proteins and plasmodesmata
c passively through cotransporter proteins only
d actively through plasmodesmata only

28 the photomicrograph shows blood cells as seen using a high-power light microscope.
: f
i o~/,% 4 if $
‘ vr a, - foe
fra ~~ . “ 1
sg at
é - @
7. ’ wt
& \ c
3 a ee
5 > : = 3
2
which row correctly identifies the different types of white blood cell?
pop a
a lymphocyte monocyte neutrophil
b monocyte neutrophil macrophage
c neutrophil monocyte lymphocyte
d phagocyte lymphocyte monocyte

29 plan diagrams of two blood vessels are shown.
fatty tissue
ye ly
i
l) fp —~4-—
5
1 2
which labels are correct?
ee
a aorta vena cava elastic smooth epithelium
fibres muscle
b artery vein collagen smooth endothelium
fibres muscle and
elastic tissue
c vein artery collagen elastic squamous
fibres fibres cells
d coronary coronary elastic smooth epithelium
artery vein fibres muscle and
elastic tissue

30 what are found in blood and tissue fluid?

1. carbon dioxide
2 fatty acids
3 white blood cells
4 proteins

a 1,2,3and4

b= 1, 2 and 3 only

c 1,2 and 4 only

d 3and 4 only

31 which reactions would be slowed down by an inhibitor of carbonic anhydrase?
1 coz + haemoglobin > carbaminohaemoglobin
2 coz + ho > h2co3
3 h,co3 > h* + hco3”
a 1,2and3 b jiand2only c t1and3only d = 2and3 only

32 which sequence of letters correctly identifies the order of events during the cardiac cycle?
t atrial walls contract
u_ impulse is delayed by a fraction of a second
v_ wave of excitation enters the atrioventricular node
w_ wave of excitation passes down the purkyne tissue
x wave of excitation spreads from the sinoatrial node
y ventricles contract
a b cc d
{ } { t { } { t
yx © wm yo @ © ®m ©

33 the diagram gives information about blood pressure in the left side of the heart during the cardiac
cycle.
ew
4 os
4 \
y \
/
! 1
| 3 1
|
i |
pressure i 2 ! key
/kpa ' ; ———— aorta
i i p
i | tereeeeeeees atrium
i |
4 i 1 ------- ventricle
i
x 3
i \/
o\i ‘ ws
iat wow oot
0 01 #02 03 04 05 06
time/s
valves open and close at the points numbered.
which row identifies the valves opening or closing at the points numbered?
atrioventricular semilunar atrioventricular semilunar
valve opens valve opens valve closes valve closes
a 1 3 4 2
b 2 4 3 1
cc 3 1 2 4
d 4 2 1 3

34 a person with no breathing conditions rests for an hour. their breathing in this time is shallow and
slow, so little air from outside the body reaches the alveoli. the person’s heart rate remains
constant.

which statement is correct?

a_ the carbon dioxide concentration in the blood in the pulmonary vein will be higher than in the
pulmonary artery.

b carbon dioxide molecules in the air of the alveoli move out of the blood by active transport.

c_ the air in the alveoli has a lower concentration of oxygen than the blood in the pulmonary
vein.

d oxygen molecules diffuse from the air in the alveoli into the blood at a slower rate than when
the person is active.

35 which statements about all bronchioles are correct?
1 they have epithelium.
2 they have goblet cells.
3 they have muscle tissue.
a 1,2and3 b 1tand3only c= 2only d = 3only

36 the diagram shows some of the pathogens that cause disease in humans and some of the ways
they are transmitted.
1 2 ww
bacterium protoctist contaminated water
pathogen method of
| transmission
3 x ¥
virus mosquito bite coughs and
sneezes
what is the correct pathogen and method of transmission for malaria?
a iandx b 2andw c 2andxxx d 3andy

37 some of the processes which result in the formation of a population of bacteria that are resistant
to a new antibiotic are listed.
1 change in reproductive success of bacteria
2 increase in frequency of the resistance allele in the population
3. increase in genetic variation within the population
4 random mutation occurs in bacterial dna
what is the correct order of these processes?
a 1335254
b 23515354
c 354>51>2
d 453>51>2

38 when bacteria are grown in a petri dish containing discs with antibiotics, there will be zones of
inhibition of bacterial growth.
antibiotic disc
zone of inhibition
area of
bacterial
growth
the chart shows the size of the zones of inhibition when a species of bacteria was incubated on
five different plates of agar, each containing a disc with a different antibiotic.
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ppr ee ee
ppr ee ee ee
el a dp ea a a
25 ddr ee se eee ee ae eee
prp eere eee eee
hate ett tt
| a im bs see eee ee
20 see eee eee eee ————————————
feeeeeeeeeeeeeeeeeeeeee] — eeeeeepeeeeeereeeeeeh
zone of poc coor cece
inhibiti ee eere, = eee) eee
nnibition 1s eee er ee
/mm an eeeeeeeeeeeehe eh hale eee ee
tof fpf peepee ff
pt eeeeeeeee eee pry [tt ry ae
be eere tt heh} = ee
bh eeeeeeeeeeepe heh ece] ee
hh fee echr eee) ere fe
searen ppt ry ptt rt ltt ry [tt
0 ptr perr | pp yy pp | preyer ae
1 2 3 4 5
antibiotic
which conclusions can be made about the most and least effective antibiotics on this species of
bacteria?
most effective | least effective
antibiotic antibiotic
a 3 2
b 4 3
cc 3 1
d 2 3

39 which blood cell type does not recognise, engulf and digest non-self particles?
a macrophages
b neutrophils
c phagocytes
d_ t-killer cells

40 repeated infections with malaria result in more effective immunity to malaria.
which type of immunity is responsible for the more effective immunity?
a artificial active
b artificial passive
c natural active
d natural passive

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