biology

1. which combination of lenses for a light microscope will give the greatest magnification?
(| evenice tens | objec es
a x5 x100
b x10 x40
cc x15 x40
d x15 x100

2 the photomicrograph shows some mesophyll tissue from a dicotyledonous leaf.
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what is the magnification of the photomicrograph?
a x280 b  x2800 c x3570 d  x7000

3. the diagram shows a typical animal cell as seen using an electron microscope.
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3
which of the numbered structures are needed for proteins to be secreted at the cell surface
membrane?
a 2,3,4and5 b 1,2and4 c i1and3 d 5only

4  lysosomes vary in shape and size, making them difficult to identify.

what describes a lysosome?

a a vesicle containing enzymes, enclosed by a double membrane, that is budded off the
endoplasmic reticulum

ba vesicle containing hydrolytic enzymes and surrounded by a single membrane, found only in
phagocytes

ca vesicle enclosed by a single membrane, containing several different hydrolytic enzymes
that may act inside or outside the cell

da vesicle surrounded by a double membrane, containing enzymes which can hydrolyse
damaged organelles in a cell

5 which statements about atp are correct?
1 it is produced in mitochondria only.
2 it can be hydrolysed to form adp.
3. it contains deoxyribose.
a 1and3 b= 1 only c 2and3 d 2only

6 a single-celled organism lives inside the body of a fish. this single-celled organism is
rod-shaped, 700m long, enclosed in a cell wall and has cytoplasm containing thousands of
copies of small, circular dna.

which statement about this single-celled organism is correct?

a_ltis a eukaryote, because it can be seen without using a microscope.
b_itis a eukaryote, because it is too large to be a prokaryote.

c_itis a plant, because it is enclosed in a cell wall.

d_itis a prokaryote, because it has small, circular dna in its cytoplasm.

7 a solution of amylase was added to a suspension of starch. the mixture was stirred and kept at
40°c for 45 minutes.
samples were then tested with various reagents.
what is the expected set of results?
test and resulting colour
benedict's test biuret test

a black blue blue

b black orange purple

cc brown blue blue

d brown orange purple

8 the diagram shows three hexose sugars.
‘ical ore ch,oh 6
cc——o c——o |
h h h oh oh
i \\ ii in a “sf
cc cc cc cc cc c
ho\t t/bn ont aa int p7bu,0n
c—f o—f “oe
h oh h oh oh h
1 2 3
which row correctly shows examples of carbohydrates in which these three hexose sugars
occur?
[ [sucrose | catlose [arise |
a 1 2 3
b 1 3 2
cc 2 3 1
d 3 2 1

9 what can occur as a result of a condensation reaction?
1. adisaccharide is formed.
2 aglycosidic bond is broken.
3 a molecule of water is produced.
4 two monosaccharides join together.
a 1,2and3 b 1,2and4 c 1,3 and4 d 2,3 and4

10 the diagram shows some relationships between features of carbohydrates.
“ty ,4 bonds
- branched
which row correctly matches the carbohydrate with some of its features?
ee ee
a amylopectin sucrose glycogen cellulose
b amylose glycogen amylopectin cellulose
cc cellulose amylopectin glycogen sucrose
d glycogen cellulose amylose amylopectin

11. which row describes a triglyceride?
[oem |
a jv jv key
b v x ¥ = correct
cc x v x = not correct
d x x

12 the diagram shows three triglycerides, x, y and z.
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xx hcoc
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lf
z hcocg po ppo loprpaorldr opp woofddpdhd oh foppp™
lf
povv< gpr vopr o9@ o%rfombxo_oalf
h,coc
what is correct for these triglycerides?
contains contains contains more
saturated unsaturated than two different
fatty acids fatty acids fatty acids
a x, y andz x and y x and y
b x, y andz z x and y
cc x and y x, y and z x, y andz
d z x and y x, y and z

13 which features of collagen result in it having high tensile strength?
1 bonds form between adjacent molecules.
2 each three-stranded molecule is held together by hydrogen bonds.
3. every third amino acid in the polypeptide is small.
4 the primary structure is held together by peptide bonds.
a 1,2and3 b 1,3 and4 c 1and2 only d 2,3and4

14 which levels of protein structure would always be changed if an enzyme works by the induced fit
hypothesis?
[| primary [secondary [teary | auatemary |
a v v j jv key
b v v x x v = always changed
cc x v x x x = not changed
d x x v x

15 the enzyme f-galactosidase can catalyse the hydrolysis of four substrates, a, b, c and d, with
similar structures.
each substrate has a different k, value.
for which substrate does b-galactosidase have the lowest affinity?
a kn=4x 10°moldm®
b kn =1x 10%moldm®
c kn=2x10“moldm®
d k,=1x10*moldm?

16 which is correct for competitive inhibitors of enzymes?
1 they occupy the active site of an enzyme.
2 they have exactly the same shape as the substrate.
3. they can be used to control the rate of enzyme activity.
4 they can bind to a site on an enzyme other than the active site.
a 1,2and3 b 1and3 only c 1only d 2,3and4

17 the diagram represents the fluid mosaic model of membrane structure.
3
2
\
6 5 a
which two of the numbered components contribute to the fluidity of the membrane?
a iand3 b 2and4 c 3and5 d 4and6

18 the cell surface membranes of some cells are largely made up of phospholipids and cholesterol,
with few proteins.
which transport mechanisms will be reduced across these membranes?
1 facilitated diffusion
2 active transport
3 diffusion
a 1,2and3 b 1tand2only c 1and3only d 2and3only

19 one of the glycoproteins present in the cell surface membrane of human cells is called icam-1.
icam-1 is a cell adhesion molecule and it is also used by the common cold virus to attach to
human cells.

which statements are true about icam-1?
1 a drug binding to icam-1 to block the common cold virus could stop cells attaching
to each other.
2 part of the icam-1 structure must be complementary to proteins in the coat of the
common cold virus.
3 the icam-1 structure must have hydrophobic parts to stabilise it within the cell
membrane.
a 1,2and3 b 1tand2only c 1and3only d = 2and3only

20 a student weighed a cylinder of potato and then put it into a test-tube containing a salt solution.
the potato cylinder was removed from the salt solution after one hour. it was blotted dry and then
reweighed. the student recorded that the potato had lost mass.

which row shows the correct explanation for the results the student collected?
water potential condition of the
of the potato cells potato cells
before soaking after soaking
a higher plasmolysed
b higher turgid
cc lower plasmolysed
d lower turgid

21 some parts of a typical human chromosome are more numerous than others.
which of the parts are listed in order from the most numerous to the least numerous?
a_ centromere, nucleotide, histone
b dna molecule, telomere, centromere
c histone, telomere, dna molecule
d_ telomere, centromere, nucleotide

22 the enzyme telomerase prevents loss of telomeres after many mitotic cell cycles.
which cells need to transcribe telomerase enzyme?
1 stem cells
2 activated memory b-lymphocytes
3 helper t-lymphocytes secreting cytokines
a 1,2and3 b 1tand2only c 1and3only d 2and3only

23 the diagram shows a cell during mitosis.

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si 7

which description correctly identifies the cell?

a aplant cell during anaphase

baplant cell during metaphase

c_ ananimal cell during anaphase

dan animal cell during metaphase

24 agene codes for the production of a protein, p53, that binds to damaged dna during interphase
and prevents its replication. a carcinogen in cigarette smoke mutates this gene.
which statement explains why this mutation may cause cancer?
a cells with no p53 are allowed to undergo mitosis.
b cells with no p53 allow their damaged dna to replicate.
c_ the carcinogen in cigarette smoke increases the rate of cell division.
d_ the p53 causes uncontrolled cell division.

25 what is the role of dna polymerase?
a_ condensation reactions to produce dna nucleotides for replication
b_ correct alignment of rna nucleotides along a template strand of dna
c_ formation of bonds to complete the sugar-phosphate backbone
d__ formation of glycosidic bonds between complementary base pairs

26 which row represents the correct features of the nitrogenous base thymine?
has a forms two hydrogen , ,
. : . ‘ ae pairs with
single ring is a purine bonds with its :
cytosine
structure complementary base
a jv v x x key
b v x v x ¥ = correct
cc x v x v x = not correct
d x x v v

27 meselson and stahl investigated dna in bacteria. they grew bacteria in a medium with only
heavy nitrogen, ‘sn, until all of the bacterial dna was heavy.
these bacteria were moved from a heavy nitrogen medium and cultured in a medium with only
light nitrogen, “n.
a sample of bacteria was collected from the second generation and their dna analysed.
hybrid dna contains both heavy and light dna.
which row shows the percentage of heavy dna strands and the percentage of hybrid dna
molecules in the second generation produced in the medium containing light nitrogen?
percentage of heavy | percentage of hybrid
dna strands dna molecules
a 25 25
b 25 50
cc 50 25
d 50 50

28 the table shows the dna triplet codes for some amino acids.
arginine gca glycine cca
arginine gcc glycine ccg
arginine gcg glycine cct
asparagine tta lysine ttc
asparagine ttg lysine yin i
stop atc proline gga
cysteine aca proline ggc
cysteine acg valine cac
the base sequence on the dna strand coding for a polypeptide is shown.
cca ttc acg gcg tta gca
two mutations occur in this sequence during dna replication.
which mutated dna would have no effect on the polypeptide synthesised?
a ccaatc acg gcg ttg gca
b  ccattc aca gca tta gca
c cca ttc acg ccg tta gcc
d cct ttc acg gcg tta gga

29 a group of students were asked to look at the photomicrograph of a cross-section of unfamiliar
material and make observations.
hes

the students described x as:

1 circular

2  ahollow tube

3 aspherical structure.
which descriptions are correct?
a 1,2and3 b 1and2only c= 1only d = 3only

30 irrigating crop plants with water containing low concentrations of salt causes an increase in the
concentration of salt in the soil.
what explains why the increase in salt concentration eventually kills the crop?
water potential | water potential direction of water
in roots in soil movement
a ¥ into the roots key
b t into the soil solution | t = water potential increases
c + out of the roots \ = water potential decreases
d lt into the roots

31 the photomicrograph shows a transverse section through part of a plant root.
which tissue inhibits the path of water through the apoplastic pathway?
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32 the table shows some information about three blood vessels, p, q and r, from a mammal.
diarnater wall percentage composition of wall
/ thickness -
mm tem
25 2 22 33 40
20 1 25 40 25
4 fl 35 25 30
which row identifies blood vessels p, q and r?
a artery vein artery
b artery vein capillary
c vein artery capillary
d vein artery vein

33 which row correctly identifies the locations in which a type of molecule or cell is present?
| type of molecule or cell lymph sieg
a antigen v v v key
b glucose v x v v= is present
cc lymphocyte x v x x = is not present
d neutrophil x jv v

34 the graph shows the percentage saturation of haemoglobin with oxygen at different partial
pressures of oxygen.
which range of partial pressures of oxygen results in the greatest change of percentage
saturation of haemoglobin per kpa?
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partial pressure of oxygen/kpa

35 how many layers of cell surface membrane separate an oxygen molecule in the air space of an
alveolus from the nearest haemoglobin molecule?
a 3 b 4 cc 5 d 6

36 which biochemical is formed and what happens to the oxygen dissociation curve of adult
haemoglobin when carbon dioxide combines with haemoglobin?
[| bechemicalomed [oxygen dsodaton cure
a carbaminohaemoglobin shifts to the left
b carbaminohaemoglobin shifts to the right
cc carboxyhaemoglobin shifts to the left
d carboxyhaemoglobin shifts to the right

37 the diagram has been used to identify four infectious diseases.
infectious disease
waterborne not waterborne
1 ra he,
virus not a virus
/ \ 4
airborne not airborne
2 3
which row correctly identifies the infectious diseases?
ee ee
a cholera measles hiv/aids tb
b cholera smallpox malaria measles
cc malaria hiv/aids tb cholera
d malaria tb measles cholera

38 how does penicillin affect bacteria?
a itinhibits dna replication by binding to nucleotides.
b it inhibits translation by preventing trna binding to ribosomes.
c_itis a competitive inhibitor of an enzyme in cell wall synthesis.
d_itis a competitive inhibitor of an enzyme in protein synthesis.

39 growth factors are chemicals that stimulate a cell to divide.
growth factors are transported around the body in the blood, and they attach to cells that have
complementary growth factor receptors on their surface.
some cells have too many growth factor receptors on their surface and so the cells continue to
divide, forming a tumour.
trastuzumab is used as a treatment for some cancers.
trastuzumab works by binding to a specific growth factor receptor on a tumour cell. this stops
the cell dividing and the cell dies.
what is trastuzumab?
a amonoclonal antibody
b= avaccine
can antibiotic
dan enzyme inhibitor

40 what describes artificial active immunity?
a protection against a pathogen by an injection of antibodies
b_ protection against a pathogen by drinking colostrum containing antibodies
c _ stimulation of lymphocytes by antigens contained in a vaccine
d _ stimulation of lymphocytes by antigens on the surface of invading pathogens

Solve 9700_s19_qp_13