biology

1. what is the definition of the resolution of a light microscope?
a the degree of sharpness produced by the microscope
b_ the greatest distance between two objects visible in the same field of view
c_ the minimum distance that allows two objects to be viewed as separate
d the size of the smallest object visible using the microscope

2 the electron micrograph shows a type of virus at a magnification of x30 000.

eo i re a
: a se ne — *
ae 2. 2 4 : — bul e :
oe i a4

what is the length of the virus?

a 2.2x10°nm

b 2.2 x 10?nm

c 2.2x10'nm

d 2.2 10°nm

3 which row correctly shows a feature of a cell structure?
site of protein
: makes lysosomes

synthesis

a_ | smooth endoplasmic | rough endoplasmic
reticulum reticulum

b ribosomes golgi body

cc rough endoplasmic ribosomes
reticulum

d golgi body smooth endoplasmic

reticulum

4 four students were asked to match the function with the appearance of some cell structures in an
animal cell.
the functions were listed by a number.
1 organises microtubules to produce the spindle during cell division
2 __ synthesis of polypeptides
3 packaging of hydrolytic enzymes that will remain in the cell
the appearances were listed by a letter.
vs membranes which surround an enclosed inner cavity
w_non-membrane bound, spherical structures
x adouble membrane with many 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?
[|] 2] 2] 2 |
a ww xx y
b www zz www
cc ¥ www z
d y z z

5 the features of some cells and cell structures that make atp are listed.
1 has outer boundary membrane and folded inner membrane
2 has peptidoglycan cell wall outside an outer boundary membrane
3 has a double boundary membrane and stacks of inner membranes
which row identifies these components?
i
a bacterium chloroplast mitochondrion
b chloroplast bacterium mitochondrion
cc chloroplast mitochondrion bacterium
d mitochondrion bacterium chloroplast

6 mitochondria are thought to have evolved from prokaryotic cells that were ingested by an
ancestral cell.
which feature have these prokaryotes lost during their evolution into mitochondria?
a cell wall
b circular chromosome
c internal membranes
d_ ribosomes

7 a student carried out the benedict's test on a sample and got a negative result.
what should the student do to confirm there are no sugars present in the sample?
a boil the sample for 5 minutes then repeat the benedict’s test
b _ boil with alkali, neutralise with hydrochloric acid and repeat the benedict's test
c _ boil with hydrochloric acid, neutralise with alkali and repeat the benedict's test
d_ repeat the benedict’s test but add more benedict’s reagent

8 the diagrams show three hexoses.
ch,oh ch,oh
t—o 0 t—o
h h hoh,c oh h oh
(a or ao rr ca
ne nn a,
ho ¢ ¢ oh h ¢ ¢ pb ho ¢ ¢ h
h oh oh h h oh
1 2 3
in which carbohydrates do these three hexoses occur?
a il 2 3
b 1 3 2
cc 2 3 1
d 3 2 1

9 the diagram shows part of the chemical structure of a naturally occurring polysaccharide.
cooh ch,oh cooh ch,oh
oo (e) ome) o
ho ho ho
oh hn ch, oh hn ch,
tt tt
(e) (0)
what types of glycosidic bonds are present?
a a-1,3 and a-1,4
b a-1,4 and a-1,6
c_ -1,3 and b-1,4
d_ £-1,4 and b-1,6

10 what is the maximum number of water molecules produced when a triglyceride is synthesised?
a 3 b 2 cc 1 do

11 what occurs during the formation of a peptide bond between two amino acids?
a oh is removed from cooh and h is removed from an r group.
b  ohis removed from cooh and h is removed from nh>.
c_ his removed from cooh and oh is removed from an r group.
d ojis removed from cooh and 2h is removed from nhp.

12 the diagram represents roles of water in living organisms.
1
carries dissolved
substances
role of
water in living
organisms 2
t - ae) provides a constant
smpeiamre cons) environment for
due to evaporation aquatic organisms
which roles are dependent upon hydrogen bonds between water molecules?
a 1,2and3 b 1and2only c 1and3only d = 2and3only

13 the diagram shows a metabolic pathway.
enzyme 1 enzyme 2 enzyme 3
reactant —————» substance x —————® substance y —————®» end product
what would be the effect of adding a small amount of a non-competitive inhibitor of enzyme 2?
a enzyme 2 would be partially denatured.
b substance x would increase in concentration.
c substance y would no longer be formed.
d the initial reactant would no longer be metabolised.

14 two enzymes are added to a solution containing a low concentration of a substrate that they can
both use.
which statement is correct?
a_ both enzymes will use equal amounts of the substrate.
b_ neither enzyme will be able to use the substrate.
c_ the enzyme with the lower vmax will use less of the substrate than the other enzyme.
d_ the enzyme with the lower v,,, will use more of the substrate than the other enzyme.

15 the diagram shows the fluid mosaic model of membrane structure.
structures 1, 2, 3 and 4 are types of molecule.
2 be
: i
é
which types of molecules are always identical?
a 1,2and3 b 1tand4 c 2and3onlyy d 4only

16 what is the role of g protein in cell signalling?
a_ to act as a membrane-bound enzyme
b_ to act as a switch releasing a second messenger
c to amplify the original signal
d_ to change the shape of the protein receptor

17 when a small quantity of phospholipid is added to a test-tube of water and then shaken
vigorously, an emulsion is formed by small droplets called liposomes.
which diagram shows the arrangement of phospholipid molecules in a cross-section of a
liposome?
a b cc d

18 what are the features of facilitated diffusion?
1 it uses protein channels in the membrane and is driven by the energy from atp.
2. it moves molecules from regions of higher concentration to lower concentration and
is driven by the kinetic energy of the molecules which are diffusing.
3 it uses protein channels in the membrane, and the maximum rate of diffusion
depends on the number of these channels.
a 1,2and3 b 1tand2only c j1and3only d = 2and3only

19 which description of cnromosome structure is correct’?

a a chromosome at the beginning of interphase consists of two identical chromatids, each
containing one linear molecule of dna.

b_ telomeres are lengths of non-coding dna found at one end of each chromatid to prevent
loss of genes during cell division.

c_ the two identical chromatids of a chromosome are held together by a centromere in which
there is no dna.

d_ the very long dna molecule of each chromatid is coiled and held together by proteins called
histones.

20 which processes involve mitosis?
clonal selection forming cells at the
of t-lymphocytes tip of a growing root
replacing skin cells
damaged by an injury

21 a drug has been developed to treat certain types of cancer. it prevents mitosis by binding to the
spindle and preventing sister chromatids being separated and moving to opposite poles of the
cell.

the photomicrograph shows cells in different phases of mitosis.
1
fy f @
a —
what represents the stages of mitosis that will be able to occur in a cell which is entering
prophase when treated with this drug?
a iand2 b 2and3 c 2only d 3and4

22 some viruses have single-stranded dna as their genetic material. this dna molecule has to be
folded to fit in the protein coat.
which statements about single-stranded dna are correct?
1 single-stranded dna cannot replicate semi-conservatively.
2 if only the percentage of cytosine is known, then the percentage of guanine can be
calculated, but the percentage of adenine and thymine cannot be calculated.
3 hydrogen bonds may be present within the dna molecule.
a 1,2and3 b 1tand2only c 1and3only d = 2and3only

23 how many statements are true tor semi-conservative replication of dna in a eukaryotic cell?
1 the process takes place in the nucleus.
2 adenine will line up against uracil on the complementary strand.
3 each new molecule will contain one strand of the original molecule.
4 if the original molecule contained 40% guanine each new molecule will contain 20%
guanine.
a 1 b 2 cc 3 d 4

24 part of the nucleotide sequence of an mrna molecule is shown, with spaces between the
codons.
cag uac agc aau cua uaa
the translation of the codons is provided.
bede amino acid
or stop
aau asn
agc ser
cag gin
cua leu
uaa stop
uac tyr
uau tyr
which events will cause the termination of polypeptide synthesis during translation?
1 deletion of c from the leu codon.
2 deletion of c from the tyr codon.
3. the ribosome reaching the uaa codon.
a 1,2and3 b 1tand2only c iand3only d = 2and3 only

25 external factors change the rate of transpiration, which also affects the water potential gradient of
cells in the leaf.
which combination is correct?
external factor changing the water potential gradient
rate of transpiration in the leaf
a decreasing temperature increases
b decreasing wind speed increases
cc increasing relative humidity decreases
d increasing sunlight decreases

26 the photomicrograph shows a transverse section through a leaf.
<< ae beeee |
eo lcs bie,
ca, ae a se on
ps ee care t ee.
wae 5 kann i y es se ha ‘
| ee ei
jss gos se ee seem s. se, at
yap le dati ete ste ca am a a
ae oy aes cs eos oa ea
eae ee
dee em wiry ce, «be ened
bae? ane 6) asd cost a
x50
which features of a xerophytic leaf are visible in this section?
1 sunken stomata
2 two layers of epithelium
3 thick cuticle
4 small surface area to volume
a 1,2,3and4 b 1and2only c_ 1and3only d 3and4 only

2/ which changes occur as carbohydrates move out of a root cell into a phloem sieve tube?
water potential in a volume of liquid
phloem sieve tube in phloem
becomes sieve tube
a less negative decreases
b less negative increases
cc more negative decreases
d more negative increases

28 the photomicrograph shows three white blood cells labelled x, y and z.
: z
eo.
which row correctly identifies these cells?
[cx [ety [iz
a lymphocyte monocyte neutrophil
b lymphocyte neutrophil monocyte
c monocyte neutrophil lymphocyte
d neutrophil monocyte lymphocyte

29 the graph represents data on blood vessels and blood flow.
fs,
i \
. in
te ; \ ey
% 4 \ x —-----
4 in _
i k y
a 4 ne zoceteesteeeteeee
7 %, ki
/ pitas sy
py + petsmagh ss,
arteries small capillaries small veins
arteries veins
which row correctly identifies the curves?
speed of pressure of total cross-
blood flow blood sectional area
a xx 4 zz
b xx z y
cc ¥ z x
d z x y

30 which components of blood are present in lymph?
white blood ‘ sodium
proteins 7
cells ions
a jv jv jv key
b v x v / = present
cc x v v x = not present
d x v x

31 what correctly describes the significance of the increase of the red blood cell count of humans

who move from living at low altitude to high altitude?

a after a few weeks at high altitude, the number of red blood cells increases to compensate for
the lower availability of oxygen in the air.

b_ at high altitude, the bone marrow produces more red blood cells to provide binding sites for
the increased number of oxygen molecules available.

c_ at high concentrations of oxygen in the blood, a cytokine stimulates the production of red
blood cells to increase the oxygen-carrying capacity of the blood.

d_ after only a few days at high altitude the number of red blood cells increases considerably to
compensate for the lower availability of oxygen in the air.

32 which structures of the human gas exchange system are supported by cartilage?
[[erenchas [broncos | vachea |
a x v v key
b x v x ¥ = cartilage present
cc v v v x = cartilage not present
d v x v

33 carbon monoxide, nicotine and tar are components of tobacco smoke.
which row correctly describes their effect on a smoker's body?
[| catoon monoxide [cone tr
a | causes loss of consciousness increases the destroys cilia on cells
at very low concentrations diameter of lining the airways
blood vessels
b forms a stable increases blood | stimulates goblet cells
compound with pressure to secrete mucus
haemoglobin
cc forms increases the settles on cells
carbaminohaemoglobin diameter of the lining the airways
coronary artery
d forms decreases the contains carcinogens
carboxyhaemoglobin heart rate

34 which statements about chronic obstructive pulmonary disease (copd) are correct?
1 the disease can often be reversed by treatment.
2 the patient's symptoms normally do not change.
3. the patient is normally over 30 years old.
4 the patient coughs frequently, producing a lot of mucus.
a 1,2and3 b 1,2and4 c 1,3and4 d 2,3and4

35 which of these causative agents of disease can be transmitted by droplet infection?
1 vibrio
2 mycobacterium
3. morbillivirus
a 1,2and3 b 1and2only c 1and3only d = 2and3only

36 the table compares total antibiotic use (x) and the percentage of antibiotic-resistant pneumonia
cases (y) in five countries.
ae ee |
country / defined dose per 1000 penicillin-resistant
people per day pneumonia cases
austria 13 10
denmark 11 4
iceland 1e 15
spain 30 50
usa 24 33
what is supported by the data?
a when x decreases there is an increase in y.
b when x increases there is an increase in y.
c when x increases it causes an increase in y.
d_ there is no relationship between x and y.

37 which statement about the development of resistance to antibiotics in bacteria is correct?
a_ all mutations in bacteria result in resistance to antibiotics.
b_ antibiotics increase the rate of mutation in bacteria.
c mutations leading to antibiotic resistance only occur when antibiotics are used to treat
pathogenic bacteria.
d lamas of antibiotic-resistant bacteria in a population only increases if the antibiotic is
used.

38 a blood cell count can indicate how many white blood cells there are in the blood.
where else in the body are white blood cells found?
1 bone marrow
2 lymph
3 lungs
a 1,2and3 b 1tand2only c j1and3only d = 2and3only

39 myasthenia gravis is a disease that results from the immune system failing to distinguish between
self and non-self. antibodies bind to a component of the junctions between a muscle and its
nerve.

what correctly describes myasthenia gravis?

a_impulses in the nerve to the affected muscle cannot be blocked.

b_ the affected muscle cannot be repeatedly stimulated.

c_ the affected muscle is permanently stimulated.

d_ the nerve to the affected muscle does not carry any nerve impulses.

40 a monoclonal antibody, specific for a virus, was treated with an enzyme to break the bonds
between the variable and constant regions.
the separated variable and constant regions were then added to cells infected with the virus.
which statements are correct?
1 the constant regions would bind to different parts of the virus antigens.
2 the viruses could be engulfed by phagocytes if they were present.
3 the variable regions would all bind to the same part of the virus antigens.
a 1and2 b 1and3 c 2only d = 3only

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