biology

1 the eyepiece lens of a microscope can be fitted with an eyepiece graticule.
which of these statements about eyepiece graticules are correct?
1. they measure the actual length of cells in micrometres.
2 they help biologists to draw cells with correct proportions.
3 they change in size when the objective lens is changed from x10 to x40.
a 1,2and3 b tand3only c_  1only d = 2only

2 a student was asked to use the scale bar shown to calculate the magnification of a cell on a
photomicrograph.
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2um
which method could the student use to calculate the magnification of the cell?
a divide the diameter of the cell by the length of the scale bar, both measured in the same units
of length
b measure the diameter of the cell in millimetres, multiply by 2000 and divide by the length of
the scale bar measured in millimetres
c_ measure the length of the scale bar in millimetres, convert to micrometres and divide by 2
d_ measure the length of the scale bar in millimetres, convert to micrometres and multiply by 2

3 which eyepiece and objective lens combination of a light microscope allows the greatest number
of cells in a field of view to be seen?
[teves os obeaive ne |
a x5 x10
b “5 x40
cc x10 x10
d x10 x40

4 which row correctly matches each cell structure with its function?
ee ee ee
a allow vesicles to move within the cell synthesises amino acids
b form cilia and centrioles produces ribosomes
cc form the spindle during prophase transports proteins
d move chromosomes during anaphase makes triglycerides and phospholipids

5 which animal cells would have the most extensive golgi bodies?
a ciliated epithelial cells
b goblet cells
cred blood cells
d smooth muscle cells

6 which of these processes will require atp?
1 transport of water in the xylem
2 semi-conservative replication of dna
3 facilitated diffusion of amino acids into the cell
a 1,2and3 b 1tand2only c 2and3only d 2only

7 which concentrations could be produced by a serial dilution of an 8.00% glucose solution?
a 4.00%, 2.00%, 1.00%, 0.50% and 0.25%
b 4.00%, 3.00%, 2.00%, 1.00% and 0.00%
c 6.00%, 4.00%, 2.00%, 1.00% and 0.50%
d 8.00%, 6.00%, 4.00%, 2.00% and 0.00%

8 a student wrote these statements about polysaccharides.
1. amylose is formed from condensation reactions between b-glucose monomers.
2 branches in amylopectin molecules form between carbon atoms 1 and 4 on
a-glucose molecules.
3 in unbranched b-glucose chains, each monomer is rotated 180° relative to its
adjacent monomer.
which of these statements are correct?
a i1and2 b 1 only c 2and3 d = 3only

9 which diagram correctly shows the formation of a peptide bond between two amino acids?
a b
h h o 4h h o h h fe)
\ |e \ | f \ | jf
fn i ne 7 h,o
h h—c—h@h hh oh hoh gy 6
to \ /
= 1 - he ihoh<
ze {| ‘ya
o7 sou h h
cc d
h h oo h oo
\ | g \ | gf
n—c—c n—c—c
/ | ‘se / | he
h ren a i p h ren
h h fe)
af \ | f n—c—c ggg
n—c—c / | ay
| \ ho @h hs ~h
h,o & 6a
h,o

10 sugars with a ring structure can also have a linear structure.
which sugar molecules could be represented by the linear structure shown in the diagram?
tn zz (e)
h ts
a oe
h es
h base
hens
a_ a-glucose, deoxyribose and ribose
b_ a-glucose only
c_ deoxyribose and ribose only
d_ deoxyribose only

11. which molecules are globular proteins?
1 amylase
2 haemoglobin
3 dna polymerase
a 1,2and3 b 1tand2only c 1and3only d 2zonly

12 when hydrolysed, which molecules have products containing a carboxyl group?
1 phospholipids
2 polysaccharides
3 proteins
a iand2 b 1and3 c 2and3 d = 3only

13 lysosomes contain many different hydrolytic enzymes that may act within cells (intracellular
enzymes) or outside cells (extracellular enzymes).
which process must occur in order for lysosomal enzymes to act outside the cell?
a active transport
b_ endocytosis
c_ exocytosis
d phagocytosis

14 ihe diagram shows an enzyme, its substrate and an enzyme/subsirate complex.
enzyme substrate enzyme/substrate
complex
which statement explains how the substrate is able to enter the active site of the enzyme?
a contact between the substrate and the enzyme causes a change in the enzyme shape.
b_ the shape of the active site and the shape of the substrate are complementary.
c_ the substrate within the active site forms hydrogen bonds with amino acids.
d when the enzyme/substrate complex forms, the tertiary structure of the enzyme changes.

15 what could be used to calculate the rate of an enzyme-catalysed reaction?
1 the appearance of product
2 the disappearance of substrate
3. the michaelis-menten constant (km)
a 1and2 b iand3 cc 1only d 2and3

16 cholesterol is an integral component of the cell surface membrane.
which statement about cholesterol is correct?
a it allows ions to pass freely through the cell surface membrane.
b_ it has a hydrophobic head and a hydrophilic tail.
c_ it helps to regulate the fluidity of the cell surface membrane.
d_ it reduces the mechanical stability of the phospholipid bilayer.

17 which type of bond in phospholipids has a role in increasing the fluidity of cell surface
membranes?
a c—c
b c=c
c c—o
d c=o

18 which of these substances can pass directly through cell surface membranes without using a
carrier protein or a channel protein?
a car
2 coz
3 cghi1206
a iand2 b 1and3 c 2and3 d = 2only

19 companion cells use aip to move hyarogen ions out of the cell and co-transporter proteins to
allow hydrogen ions to return with sucrose molecules.
which two processes are involved in this movement?
a active transport and diffusion
b active transport and facilitated diffusion
c_ exocytosis and diffusion
d_ exocytosis and facilitated diffusion

20 how many copies of each different dna molecule will be found in a cell at the start of each of
these stages of the mitotic cell cycle?
[nla [ee [ine
a 1 1 2
b 1 2 1
cc 2 1 2
d 2 2 2

21 three parts of a chromosome and their functions are listed.

part
p1 centromere
p2_ histone proteins
p3 telomere
function
f1 packages dna into compact structures
f2 holds two chromatids together
f3 prevents loss of genes

which combination is correct?

a ptandf1 b p1andf3 c p2and f2 d p3andf3

22 the graphs show various distance measurements taken from metaphase of mitosis onwards. the
graphs are to scale when compared to one another.
xx
distance
time
y
distance
time
z
distance
time
which row correctly identifies the distance measurement for each graph?
ee ee
a distance between distance between distance of centromeres
poles of spindle sister chromatids from poles of spindle
b distance between distance of centromeres distance between
poles of spindle from poles of spindle sister chromatids
c | distance of centromeres distance between distance between
from poles of spindle poles of spindle sister chromatids
d | distance of centromeres distance between distance between
from poles of spindle sister chromatids poles of spindle

23 a culture of bacteria was allowed to reproduce using nucleotides containing the heavy isotope of
nitrogen (‘°n). after several generations, all of the bacterial dna molecules contained heavy
nitrogen.

dna was extracted from a sample of the culture, mixed with caesium chloride solution and spun
at high speed in a centrifuge. in this process, dna molecules of different masses separate into
bands at different positions in the centrifuge tube. the heavier the dna molecules, the closer to
the bottom of the centrifuge tube that a band forms.
the diagram shows the position of the dna molecules containing heavy nitrogen in the centrifuge
tube.
k
l
m
the culture of bacteria was then allowed to reproduce using nucleotides containing the light
isotope of nitrogen (“4n).
dna samples were taken and separated by centrifugation after the bacteria had divided once and
again after the bacteria had divided twice.
in which positions would the dna be found after the cells had divided once and after the cells
had divided twice?
| | after dividing once after dividing twice
a half at k and half at l quarter at k, quarter at m and half at l
b half at k and half at m quarter at k, quarter at m and half at l
cc all at l half at k and half at l
d all at m half at l and half at m

24 the diagram represents a molecule of atp.
p

_t a

r

what are the components of atp labelled p, q and r?
a adenine deoxyribose phosphates
b adenosine pentose a phosphate group
cc adenosine ribose phosphorus
d purine pentose phosphates

29 ihe table shows three anticodons for diterent amino acids.
alanine cgu
histidine gua
serine uca
which dna triplet on the dna template strand codes for the amino acid serine?
a agu b tca c tgt d uca

26 the photomicrograph shows a transport tissue in the stem of a grape vine.
t
i ee en ag ts =
= ——— =
- a : a
hep el — ——
oe en , eit — [_——
br tok ° a on ji
a toe — a
what is the structure labelled t?
a companion cell
b _ sieve plate
c sieve tube element
d_ xylem vessel element

27 the diagrams show transverse sections of parts of a plant. transport tissues are labelled 1 to 6.
leaf stem root
p 3
5
| o85)‘
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@geseg m0088 0.2 "
pee q2
2
which row shows tissues that mainly transport water and tissues that mainly transport sucrose?
mainly transport mainly transport
water sucrose
a 1 and3 4and6
b 2 and 3 4and5
cc 3 and 5 2 and 6
d 4and6 2 and 3

28 what will increase the rate of transpiration?
1 increasing the humidity
2 increasing the light intensity
3 decreasing the temperature
4 decreasing the wind speed
a 1,2and3 b 1,3 and4 c 2only d 4only

29 which properties of water are important for transport in xylem?
1 cohesion
2 adhesion
3 high energy requirement for evaporation
4 good solvent properties
a 1,2 and 4 b 1and4 only c 2,3and4 d 2and 3 only

30 which statement about the blood flow in the cardiac cycle is correct?

a blood flows into the aorta through the semilunar valve due to contraction of the right
ventricle.

b_ blood flows into the left atrium through the pulmonary artery when the wall of the left atrium
relaxes.

c_ blood flows into the right atrium through the vena cava when the wall of the right atrium
relaxes.

d_ blood flows into the right ventricle through the semilunar valve due to contraction of the right
atrium.

31 which of these statements about the formation of haemoglobinic acid are correct?
1 it depends on the formation of carbaminohaemoglobin.
2 it removes excess hydrogen ions preventing the blood becoming too acidic.
3 itis linked to the action of carbonic anhydrase.
a 1,2and3 b 1and2only c 1 only d 2and 3 only

32 what can combine with the haem group of a haemoglobin molecule?
1 oxygen
2 carbon dioxide
3. carbon monoxide
a 1,2and3 b 1tand3only c 2and3only d_= 3only

33 which factors would help a person to adjust from living at a low altitude to living at a high
altitude?
1 formation of fewer red blood cells
2 anincrease in the oxygen-carrying capacity of the blood
3. anincrease in the output of blood by the heart
a 1,2and3 b 1and2only c 1and3only d = 2and3only

34 chronic obstructive pulmonary disease (copd) includes bronchitis and emphysema.
which symptom is specific to emphysema?
a excess mucus secretion by the goblet cells
b _ inflammation of the bronchial epithelium
c ioss of elasticity of the alveolar walls
d thickening of the smooth muscle of the bronchi

35 what identifies the structures present in a bronchus?
ey )
goblet cells

36 which of these terms can be used to describe the role of mosquitoes in the transmission of
malaria?
1 malarial parasite
2 pathogen
3 vector
a 1,2and3 b 1tand2only c 1and3only d_= 3only

37 bacteria that infect skin wounds can become resistant to the antibiotic commonly used to kill

them.

which statement explains how these bacteria could become resistant to the antibiotic?

a exposure to the antibiotic causes a change in the bacterial cell wall, preventing the antibiotic
from working.

b other bacteria that normally protect the skin against infection are killed by the antibiotic,
allowing the infectious bacteria to survive.

c random mutations in dna allow some of the bacteria to survive in the presence of the
antibiotic.

d_ the antibiotic causes the bacterial dna to mutate, allowing the bacteria to survive in the
presence of the antibiotic.

38 some children are born with severe combined immunodeficiency (scid).
children with this inherited disease do not normally have any t-lymphocytes and suffer from
many infectious diseases.
how may these children be cured from scid?
a transfusion of antibodies
b_ treatment with stem cells
c use of different antibiotics
d vaccination against all diseases

39 the hybridoma method is used for the production of monoclonal antibodies.
which two types of cell are used in this method?
a __ stem cell and b-lymphocyte
b_ stem cell and t-lymphocyte
c_ tumour cell and b-lymphocyte
d_ tumour cell and t-lymphocyte

40 a vaccine is used to create artificial active immunity. after being given a vaccine, it will take a
period of time before a person develops long-term immunity against the disease.
which statement about this period of time explains this delay?
a no memory cells have been produced from b-lymphocytes.
b- noplasma cells have been produced from b-lymphocytes.
c_ the primary immune response has not produced enough antibodies.
d_ the secondary immune response has not produced enough antibodies.

Solve 9700_m18_qp_12