biology

1. which statement about the light microscope is correct?
a as the smallest distance to see two points as distinct separate points decreases, the
resolution also decreases.
b_ ifthe resolution is 220 nm, then a bacterium 0.2 1m in diameter will not be visible.
c if the wavelength of light is 600nm, then two membranes 300nm apart will be visible as two
distinct membranes.
d__ using visible light of a longer wavelength, such as red light, will improve the resolution.

2 the diagram shows a stage micrometer scale viewed with an eyepiece graticule, using a
magnification of x200.
using the same magnification, a chloroplast is measured as 4 eyepiece graticule divisions long.
how long is the chloroplast?
a 1.0x10'um
b 4.0 x 107m
c 25x 10'um
d 2.5x107um

3  acell was supplied with cytosine labelled with radioactive carbon.
in which cell structure would radioactivity be detected first?
a_ endoplasmic reticulum
b_ golgi body
c nucleus
d_ ribosome

2% which statement supports the fact that mature plant cells can carry out the same role as
lysosomes?
a arrange of hydrolytic enzymes can be found within mature plant vacuoles.
b_ glycogen, found within vesicles, can be hydrolysed to glucose molecules.
c single membrane-bound vesicles are formed from plant golgi bodies.
d_ vesicles, formed from smooth endoplasmic reticulum, contain enzymes.

6 astudent carried out four tests for biological molecules on a sample of milk.
the tests and their results were as follows.
e heating to 80°c with benedict's solution gave a green colour.
e adding biuret solution gave a purple colour.
e adding iodine solution gave an orange colour.
e boiling with acid, followed by neutralisation, then heating to 80°c with benedict's
solution gave a brick red colour.
which conclusion about these results is correct?
a only protein and reducing sugar present
b__ only protein and non-reducing sugar present
c only protein, reducing sugar and non-reducing sugar present
d only starch, protein and sugar present

7 the diagrams show four monosaccharides with the formula cgh;20.¢.
1 2 3 4
ch,oh ch,oh ch,oh ch,oh
h oh h ooh h oh h oh

h h h h
oh h oh h h h oh ho

ho oh ho h ho oh ho oh
h oh h oh oh oh h h

which diagrams show glucose molecules?

a 1and2 b i1and3 c 2and3 d 3and4

8 which bonds will be broken when a molecule of glycogen is broken down?
1 a-1,4
2 £-1,4
3 a-1,6
4 b-1,6
a 1,2and3 b iand3only c 2,3and4 d 2and4 only

9 the diagram shows the amino acids in a polypeptide.
key
type of amino acid
. | polar basic
x» polar acidic
ig gee lys <>» polar
ee (leu) (__) non-polar
(val) —-
‘ lys <ciu>
(met) arg che)
ne) _
(val) (met) his (ala)
z > @
c terminal end cai)
/ lys
n terminal end
an enzyme catalyses the hydrolysis of any peptide bond between a non-polar amino acid and
any polar amino acid.
how many small peptides and single amino acids will be formed by the action of this enzyme?
small single
peptides amino acids
a 6 1
b 8 1
cc 12 3
d 13 4

10 aperson with diabetes is unable to make enough of the protein insulin.
some forms of diabetes can be treated by using insulin produced by animals. scientists have
compared the amino acids in insulin produced by animals to human insulin.
which level of protein structure were the scientists studying?
a primary
b_ secondary
c tertiary
d quaternary

11 the diagrams show four fatty acids, each with a chain of 18 carbon atoms.
which fatty acid, as part of a phospholipid molecule, would contribute most to the fluidity of a cell
surface membrane?
bbp pbplpwefosfowfot wy ial
b pobgeo prbrkg? rp pop orrbp 3h" gfp rgf” neal
clr post stoo oo oy ow” iia
d fs ff pp 7 fo

12 which levels of protein structure are maintained by disulfide bonds?
a_ secondary, tertiary and quaternary
b | tertiary and quaternary only
c quaternary only
d _ tertiary only

13 an experiment was conducted to investigate the effect of temperature on the activity of the
enzyme f-glucosidase. the enzyme was tested when in solution (free) and when immobilised in
alginate beads.

the results are shown in the graph below.
120
100
80
b-glucosidase
activity 60
/arbitrary units
40
immobilised
20 free enzyme
enzyme
0
0 10 20 30 40 50 60 70 80 90100
temperature /°c
which statement about the effect of immobilisation of b-glucosidase is correct?
a lt increases the kinetic energy of the enzyme.
b it inhibits the activity of the enzyme.
c_ itreduces the optimum temperature of the enzyme.
d_ it stabilises the enzyme against denaturation.

14 an investigation was carried out into the effect of an increasing concentration of substrate
molecules on the rate of an enzyme-catalysed reaction. all other variables were standardised.
which statement is correct?

a_ the rate increases to a maximum and then levels off.
b_ the rate increases to an optimum and then decreases.
c_ the value of k,, will increase.

d the vax will never be reached.

15 which features are correct for a competitive inhibitor of an enzyme-catalysed reaction?
rate of reaction
binds to changes shape | _ similar shape affected by
active site of enzyme to substrate concentration
of inhibitor
a v x v v key
b v x x v ¥ = correct
cc x v v x x = incorrect
d x v x x

16 liver cells contain membrane-bound organelles called peroxisomes, which contain the enzyme
catalase. this enzyme hydrolyses hydrogen peroxide into water and oxygen gas.
a student cut two identical sized pieces of liver and placed one in a refrigerator at 5°c and the
other in a freezer at -18°c.
after 12 hours both pieces were raised to room temperature and placed in equal volumes of
hydrogen peroxide.
the liver that had been at —-18°c produced bubbles of oxygen more rapidly than the liver that had
been at 5°c.
which statement explains why the liver that had been at -18°c produced bubbles of oxygen
more rapidly than the liver that had been at 5°c?
a at5°c the cell surface membrane allowed water to enter cells and dilute the catalase.
b_ freezing at -18°c made the cell walls more permeable to hydrogen peroxide.
c ice crystals damaged the cell membranes of the liver cells at -18 °c.
d_ the higher temperature had denatured some of the catalase.

17 which of these processes allow movement in both directions across cell surface membranes?
1 active transport
2 diffusion
3 facilitated diffusion
4 osmosis
a 1,2,3and4 b t1and4only c 2and3o0nly d 2only

18 the diagram shows an experiment in which two different cell surface membranes were joined to
form a single large membrane.
the outer surface of one membrane contained molecules of protein p and the outer surface of
the other membrane contained molecules of protein q.
the positions of the two proteins in each membrane were observed just before they were joined
together and 1 hour after they were joined.
protein p protein q
5 oo ° 2 @o
+ eo ° —_—> @ ee 7
pe °
°
joined membrane after 1 hour

which statements are correct?

1 this provides evidence for the fluid mosaic model of cell membranes.

2 this shows that proteins can move freely in cell membranes.

3. this shows that the membrane is fluid but the proteins are not.
a 1,2and3 b 1and2only c tand3only d 2and3only

19 which row describes osmosis across a cell surface membrane?
moves molecule
molecule uses energy ‘
down a concentration
moved from atp :
gradient
a solute v v key
b solute v x /¥ = correct
cc solvent x jv x = incorrect
d solvent x x

20 what describes a telomere?
a acell structure composed mainly of protein and involved in cell division
b_aprotein that associates with dna to help condense it
c_ aregion of dna that links two sister chromatids together
d_ aregion of repetitive nucleotide sequences at the end of a chromatid

21 uncontrolled cell division can form tumours.
which statement is correct for tumour cells only?
a metaphase does not take place.
b_ cytokinesis does not occur.
c_ interphase takes less time.
d_ they have mutated dna.

22 which of these events are part of mitosis?
1 interphase
2 anaphase
3. cytokinesis
a 1,2and3 b 1and3only c = 1only d = 2only

23 rifampicin is an antibiotic used to treat tuberculosis.
it works by inhibiting rna polymerase in bacteria.
which of these processes are prevented by this antibiotic?
1 dna replication
2 transcription
3 translation
a 1,2and3 b 1and2only c 2and3only d = 3only

24 a gene codes for the sequence of amino acids in a single polypeptide. haemoglobin consists of
two a-globins and two b-globins.
how many genes are needed to code for a single haemoglobin molecule?
a 1 b 2 cc 4 d 8

25 a single substitution in an allele of the gene coding for haemoglobin results in sickle cell
haemoglobin.
the mrna sequence for three amino acids for normal haemoglobin is shown.
ccugaagag
the mrna sequence for sickle cell haemoglobin is shown.
ccuguagag
the table shows some of the triplet codes for two amino acids.
dna triplet codes amino acid
ctc glu
ctt glu
cat val
cac val
which row is correct for the substituted dna nucleotide of the allele and the substituted amino
acid of the protein?
tata
nucleotide acid
a a glu
b a val
cc t glu
d t val

26 what is the minimum number of hydrogen bonds in a length of dna containing 700 base pairs?
a 350 b 700 c 1400 d 2100

27 the photomicrograph is a section through a plant organ.
which label identifies the xylem vessels?
eger eia bag sore,
ey ine ge
fol rely hein. vine itipey or reee
ls seater @ ole ign | out o. a
lo eae a co ea
gi et [ a paw 6 ser
big apres toe ™ ( ee
nike | ae ee ee bly eae
wier. yo sa as eessce ua.
whore 5 ay oe cee
es ee emeeeeemec@ere b
ies st jee osgeo cr:
we ots ec
a pae ee ee
we lay oo ct ae
were 1 sa aay
estonia y. a 4 { pa tg )
i eee marno seer a °
sr” pe@euseeee@seen: 2:
sess ot i aa oo or ee con teens oem .
sere, cere | seuss d

28 which of these statements correctly describe transport pathways in dicotyledonous plants?
1 inthe apoplast pathway, water may move through plasmodesmata.
2 inthe symplast pathway, water may move through intercellular spaces.
3. the apoplast pathway may be blocked by the casparian strip.
a 1and2 b iand3 c 2and3 d = 3only

29 mass flow is the bulk movement of materials from one place to another.
which vessels carry fluids by mass flow?
1 artery
2 phloem sieve tube
3 vein
4 xylem vessel
a 1,2,3and4
b= 1,2 and 3 only
c 1 and 3 only
d 2and4 only

30 amino acids move from a phloem sieve tube element into a root cell.
which changes to the water potential and the volume of liquid in the phloem sieve tube element
are correct?
| | water potential | volume of liquid
a | becomes higher decreases
b_ | becomes higher increases
c | becomes lower decreases
d | becomes lower increases

31 the table shows the volume of water taken up over a 10 minute period for two species of plant, x
and y.
time water uptake /mm*

2 4.2 1.2

4 18 2.3

6 10.9 37

8 13.3 44

10 16.9 4.9
both plants were tested at the same time, in the same room and using identical potometers. a
student concluded that y was a xerophyte so lost less water.
what feature of the experiment could bring this conclusion into doubt?
a_ the student did not control air flow or temperature surrounding the plants.
b_ the student did not leave the plants to acclimatise to their surroundings.
c_ the student did not take measurements at 0 minutes.
d_ the student did not take account of the area of leaves.

32 what happens during left ventricular systole?

a_ the atrioventricular node causes the immediate contraction of the ventricle, causing the
atrioventricular valve to close.

b_ the purkyne tissue between the atrium and ventricle causes the ventricle to contract, closing
the atrioventricular valve and opening the semilunar valve.

c_ the sinoatrial node causes the atrium to stop contracting and the blood pressure in the
ventricle to increase above that in the atrium.

d_ the wave of excitation causes the ventricle to contract so that the blood pressure in the
ventricle is higher than in the aorta, opening the semilunar valve.

33 the photograph shows blood cells as seen using a high power light microscope.
. ps ge f
“@ " a . 4
- a 4 » ; a 1
© a
: pd ’ ph
_ jaa = (i?
. ee : \
id a : oe a
2
which row correctly identifies the different types of white blood cell?
ee ee ee
a lymphocyte monocyte neutrophil
b monocyte neutrophil macrophage
cc neutrophil monocyte lymphocyte
d phagocyte lymphocyte monocyte

34 which of these processes are responsible for the bohr shift?
1 carbon dioxide reacts with haemoglobin to form carbaminohaemoglobin.
2 carbon dioxide reacts with water to form carbonic acid.
3 haemoglobinic acid is formed from the dissociation of carbonic acid.
a 1,2and3 b 1only c 2and3only d_ 3only

35 the photomicrograph shows a cross-section through a bronchus.
per
teen, ye “a xf a > be 2 mt 5
y{ = “ss ~ = = sas = ba
= ee a
ss iia a es =o
2959 i ns a
sy 4g 2 8? 9 =a —
ss ) 34,078 ion . ia «
\ nra as ai) ¢
- soa + ss ni j b | a s
what is the function of the tissues x and y?
a
a secrete mucus prevent collapse of the airway
b support the airway dilate airway
cc trap dust and dirt secrete mucus
d waft dust and dirt upwards constrict airway

36 which flow diagram correctly describes the effect of tar entering the lungs?
carcinogens
come into ‘ uncontrolled mass of cells
a i — mutationoccurs —-> a >
contact with cell division produced
dna
goblet cells ies phagocytes causes
accumulates ——
b secretemore —> ealsini > attracted by — irritation and
mucus : ng inflammation coughing
infection
goblet cells ; phagocytes iiass of cells
c secretemore -—» mutationoccurs —- _ attracted by >
‘ . produced
mucus inflammation
phagocytes elastase
d attracted by — mutationoccurs —> ungontralled — destroys the
; f cell division
inflammation alveolar walls

37 the antibiotic penicillin prevents the formation of cross-links between peptidoglycans during
bacterial cell wall synthesis by blocking the enzyme transpeptidase.
which statements describe the action of penicillin on bacteria?
1 it is an enzyme inhibitor.
2 it weakens the bacterial cell wall.
3 it will work at any stage during the bacterial life cycle.
a 1,2and3 b 1and2only c 1and3only d = 2and3only

38 which pathogens are spread by droplet infection?
1. mycobacterium tuberculosis
2 vibrio cholerae
3 morbillivirus
a 1,2and3 b 1and2only c 1and3only d = 2and3only

39 the flow diagram shows the events following activation of a t-lymphocyte by binding to antigens
on an infected cell.
t-lymphocyte
helper cells killer cells
b-lymphocytes x 4 more
activated killer cells
z. memory
cells
which row correctly identifies x, y and z?
ee ee ee
a memory cells macrophages antibodies
b memory cells memory cells plasma cells
cc neutrophils memory cells plasma cells
d plasma cells neutrophil memory cells

40 smallpox was eradicated from the human population by a worldwide preventative programme.
which type of immunity was triggered in people who were treated as part of this programme?
a artificial active immunity
b artificial passive immunity
c natural active immunity
d_ natural passive immunity

Solve 9700_w17_qp_13