biology

1. which cell organelles are clearly visible when viewed with a light microscope at high power
(x400)?
ribosomes endoplasmic centrioles chloroplasts
reticulum
a v v x x key
b v x v x v = clearly visible
cc x v v v x =not clearly visible
d x x x v

2 microvilli and root hairs are characteristic structures of some cell types.
which row identifies some features of a microvillus and a root hair?
more than one
surrounded
present ona
by cell wall
cell
a root hair microvillus
b microvillus microvillus
cc root hair root hair
d microvillus root hair
a

3 the photomicrograph is of a plant cell. the cell is 25 1m in width from x to y.
er. 5
oy yw
a, —
. >
j
xe v i
i eg me
~ ae }
. sous :
; \ \ ee f sg j = ~
j
what is the magnification of the photomicrograph?
a 2.0x10' b 2.0 x 10? c 2.0 x 10° d 2.0x 10*

4 which eukaryotic cell structures all contain nucleic acids?
a cytoplasm, golgi bodies, mitochondria, nuclei
b_ centrioles, chloroplasts, mitochondria, ribosomes
c_scentrioles, mitochondria, nuclei, ribosomes
d_ chloroplasts, mitochondria, cytoplasm, ribosomes

5 which statements about viruses are correct?
1 they contain dna or rna.
2 they use host cells to synthesise virus proteins.
3 they can have a protective coat of peptidoglycan.
a 1,2and3 b 1tand2only c 1and3only d = 2and3only

6 what are teatures ot prokaryote cells, cnioroplasts ana mitocnonaria¢
ribosomes smaller circular
than 80s dna
surrounded by a
double membrane

7 a student used benedict’s solution to test a sample known to contain carbohydrate.
at the end of the test the solution was blue.
which carbohydrate could be present in the sample?
a_ glucose
b fructose
c_ maltose
d_ sucrose

8 sugars with a ring structure can also have a linear structure.
h
bo
h tion
hob
h boon
h — boon
lon
which sugar molecules could be represented by the linear structure in the diagram?
1 ribose
2 deoxyribose
3 glucose
a 1and2 b iand3 c 2and3 d = 3only

9 which row matches each molecule to a type of bond that is present?
([_estertend | hycrogen bond | este bone |
a amylase haemoglobin catalase
b glycerol glycogen collagen
cc lipid amylopectin amylose
d phospholipid cellulose antibody

10 which row shows features of a carbohydrate polymer found inside animal cells?
an1,4 o-1,6 shape of
glycosidic glycosidic molecule
bonds bonds
a v jv branched key
b v x helical v = present
cc x j branched x = absent
d x x helical

11 the statements describe the structure of a polysaccharide found in the cell walls of certain plants.
1 the polysaccharide is composed of two different monosaccharides.
2 the monosaccharides are joined by 1,4 glycosidic bonds.
3 the polysaccharide contains pentose sugars.
which statements are also true for cellulose?
a 1and2 b 1and3 c 2and3 d = 2only

12 the general formula for a saturated fatty acid is c,h2,oq2.
which of these fatty acids are unsaturated?
1. ciohigcooh
2  cish31cooh
3. c17h31cooh
4  cish32cooh
a 1,2and3 b 1,2and4 c 1,3and4 d 2,3and4

13 what enables triglycerides to perform their functions in living organisms?
1 triglycerides have hydrophobic and hydrophilic regions.
2 triglycerides have a high ratio of carbon—hydrogen bonds to carbon atoms.
3. hydrolysis of triglycerides releases metabolic water.
a iand2 b 1and3 c 2and3 d 2only

14 the diagrams show three examples of different bonds.
bond 2
bond 1 o bond 3
\ | l | {
nh----o== —c—-+n— —ch,—s-——-s—ch,;—
/ |
h
which bonds can hold the quaternary structure of proteins together?
a 1,2and3 b 1and2only c t1and3only d = 2and3only

15 which row correctly describes the primary structure, secondary structure, tertiary structure and
quaternary structure of some proteins?
primary secondary tertiary quaternary
structure structure structure structure
a determines the depends on defines the overall formed when two
folding of the hydrogen bonding shape and folding or more identical
polypeptide between the of the protein polypeptides join
side-chains of together
amino acids
b defines the order usually forms is held together by found in globular
of amino acids in immediately after all the types of proteins such as
the polypeptide polypeptide bonding that haemoglobin but
synthesis occur in proteins never in fibrous
proteins
cc involves covalent involves essential for the formed when two
bonds only interactions function of or more
between —-h and enzymes and polypeptides join
=o receptors together
d involves peptide involves folding changes can involve
bonds between between local reversibly when hydrogen bonds,
the side-chains of regions within a bound to covalent bonds
amino acids polypeptide non-competitive and hydrophobic
molecule inhibitors interactions

16 which relationships could be investigated using a colorimeter?

1 the effect of light intensity on the rate at which a solution of a light-sensitive dye
changes from green to colourless

2 the effect of temperature on the rate of breakdown of cell membranes in tissues with
pigmented cells, such as beetroot (red beet)

3. the effect of ph on the rate of release of oxygen from the breakdown of hydrogen
peroxide by catalase

4 the effect of light intensity on the rate of change of skin colour of lizards that become
paler in bright light

a 1,2,3and4 b t1and2only c 1and4only d = 2and3only

17 which transport mechanism does not require a concentration gradient to be present in order to
take place?
a exocytosis
b facilitated diffusion
c_ osmosis
d transpiration

18 high concentrations of ethanol disrupt cell membrane structure by denaturing proteins and
increasing the separation of adjacent phospholipid molecules. as a result, cell membranes can
decrease in thickness by up to 30% and become more permeable.

yeast cells release ethanol as a waste product of metabolism. in response to increased ethanol

concentration in their environment, yeast cells are able to increase the tolerance of their cell

membranes to ethanol.

which statement correctly explains a response to ethanol that could account for the increase in

tolerance of yeast cell membranes to ethanol?

a_ decreasing the ratio of saturated fatty acids to unsaturated fatty acids within cell membranes
helps to prevent the tails of phospholipids on one side of the bilayer from sliding past the tails
of phospholipids on the other side of the bilayer.

b_ increasing the proportion of palmitoleic acid (a c16 unsaturated fatty acid) to oleic acid (a
c18 unsaturated fatty acid) in the phospholipids of the bilayer increases the fluidity of the cell
membrane.

c_ activating a cell-signalling pathway triggers the unfolded protein response in the endoplasmic
reticulum. the unfolded protein response pauses protein synthesis and initiates cell death in
yeast cells with a high proportion of mis-folded proteins.

d_ increasing the proportion of ergosterol in the cell membrane prevents the accumulation of
polar molecules, such as ethanol, within the cell. ergosterol in yeast cells has a similar effect
on membrane permeability as cholesterol in mammalian cells.

19 in an investigation, a plant cell was placed in pure water.

the initial rate at which water molecules entered the cell, r, was greater than the initial rate at

which water molecules left the cell.

in a second investigation, a plant cell of the same type was placed in a solution with a water

potential equal to that of the cell contents.

what will happen in the second investigation over a period of five minutes?

a water molecules will not enter or leave the cell because the water potential of the cell
contents is equal to that of the solution.

b_ water molecules will enter and leave the cell in equal amounts, both at an initial rate that is
less than r in the first investigation.

c water molecules will enter and leave the cell in equal amounts, both at an initial rate that is
greater than r in the first investigation.

d water molecules will enter and leave the cell in equal amounts, both at an initial rate that is
equal to r in the first investigation.

20 [he protein po3 is produced in a cell in response to dna damage. inis protein stops the cell
cycle for a short time just before the dna is replicated, so that the dna can be repaired.
at which phase of the cell cycle will this stop occur?
a m b g, c ss dg

21 some parts of a typical human chromosome are more numerous than others.
which 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 which row correctly describes a stage of mitosis?
a prophase disappears replicate spindle microtubules
begin to form
b metaphase not present move to the spindle microtubules
poles of the cell fully formed
cc anaphase begins to reform split into two some spindle
microtubules shorten
d telophase reforms at maximum spindle microtubules
distance from cell break down
equator

23 the diagram represents a nucleotide containing adenine.
which statements about this nucleotide are correct?
1 the carbohydrate is a pentose.
2 the base contains nitrogen.
3 base pairing occurs with uracil.
4 adenine is a pyrimidine.
a 1,2,3and4
b 1,2 and 3 only
c 1 and 2 only
d 3and4only

24 which row is correct for the replication of a dna molecule?
direction of dna erizyinie thatadss
; complementary nucleotides to
synthesis :
lagging strand

a 3’ to 5’ dna polymerase
b 2 tos dna ligase
cc 5' to 3’ dna polymerase
d 5’to 3’ dna ligase

25 some students were asked to look at the photomicrograph of a cross-section of unfamiliar
material and describe what they could see.
‘a g ‘
* ~ p
- o
” . «
« f
>
cod .
a“ '
= =
p . 4
? :
’ -
.
7
: ‘ , *
» 7 » . ‘ .
the students described the cross-section of f as:
1 circular
2 a hollow tube
3. spherical.
which descriptions of the cross-section of f correctly state what the students could actually see?
a 1,2and3 b ‘1and2only c 1 only d 3only

26 the diagram shows the relationship between phloem sieve tube elements, xylem vessel
elements and companion cells.
1 3 5
which row correctly identifies what could be represented by the numbers 1, 2, 3, 4 and 5?
a ee
a companion endoplasmic phloem sieve no xylem vessel
cells reticulum tube elements nucleus elements
b companion nucleus phloem sieve cytoplasm xylem vessel
cells tube elements elements
cc phloem sieve mitochondria companion nucleus xylem vessel
tube elements cells elements
d xylem vessel no phloem sieve vacuole companion
elements cytoplasm tube elements cells

27 why does an air bubble in a xylem vessel element stop the flow of water?
1 loss of adhesion
2 _ loss of cohesion
3. collapse of xylem vessel element
a 1,2and3 b 1tand3only c 1 only d = 2only

28 which changes to the water potential and the volume of solution in a phloem sieve tube occur
when amino acids are moved into a sink from the phloem sieve tube?
water potential in | volume of solution
the phloem sieve in the phloem
tube becomes sieve tube
a higher decreases
b higher increases
cc lower decreases
d lower increases

29 which feature of some xerophytic leaves reduces the rate of transpiration by decreasing the
water potential gradient between the internal leaf surface and the atmosphere?
aa thick waxy cuticle on the upper surface of the leaf
b_ leaves reduced to spines with a small surface area to volume ratio
c_ stomata located in sunken pits on the leaf surface
d_ elongated leaves that are swollen storing large amounts of water

30 the diagram shows a cross-section through a mammalian heart.
h
ey g

which chambers of the heart are represented by g and h?
ee

a left ventricle right ventricle

b right atrium left atrium

cc right atrium right ventricle

d right ventricle left ventricle

31 blood entering the heart from the vena cava passes through, or past, several structures before
entering the lungs.
five of these structures are included in this list.
atrioventricular node
aorta
semilunar valve
left atrium
pulmonary vein
purkyne tissue
sinoatrial node
pulmonary artery
after arranging these five structures in the correct order of blood flow from the vena cava to the
lungs, which structure will be third?
a atrioventricular node
b- purkyne tissue
c_ semilunar valve
d - sinoatrial node

32 the bar charts show the quantity of endothelial tissue, elastic tissue and muscle tissue in the
walls of three blood vessels, p, q and r.
key
| endothelial tissue
| elastic tissue
hi muscle tissue
p q r
quantity quantity | quantity
tissue tissue tissue
which row correctly identifies the three blood vessels?
a elastic artery muscular artery vein
b vein elastic artery muscular artery
cc muscular artery elastic artery vein
d elastic artery vein muscular artery

33 the maximum pressure in each of the four chambers of a healthy human heart was recorded
during one cardiac cycle. the maximum pressures recorded were 3mmhg, 10mmhg, 25mmhg
and 120mmhg.

which value was recorded for the right ventricle?
a 3mmhg b 10mmhg c 25mmhg d 120mmhg

34 the graph shows the pressure changes in three structures of the right side of the heart during
the cardiac cycle.
an
uy, \
i \
pressure | \ t
\
| \
| \
age | tity
ese nu ee ee ae
0 0.2 0.4 0.6 0.8
time/s
what is represented by the line labelled t?
a pressure changes in the pulmonary artery
b pressure changes in the right atrium
c pressure changes in the right ventricle
d pressure changes in the vena cava

35 which statement helps to explain why there is no cartilage in the walls of the bronchioles?
a cartilage would make the bronchioles too narrow.
b gases must diffuse across the walls of the bronchioles.
c smooth muscle is sufficient to support the walls of the bronchioles.
d_ the bronchiole walls do not need to change shape.

36 the photomicrograph shows a cross-section of part of the gas exchange system of a mammal.
. en j4 48
wt as. ea
‘. z > "“ yf = mh
gbr 3 ug
ree sp as
a gr as
fi va. y
4h wie vv ff,
ed fy 7
* by ve by
ie 3 a * . % > ot ene £ ns . of
ee saweite mee pers a i ¥
sota liah™ k )
fuse tas > me. 1.
what is shown by the line labelled v?
a __ the diameter of an alveolus
b the diameter of a bronchiole
c_ the diameter of a capillary
d_ the diameter of a trachea

37 which feature of the disease cholera decreases the spread of the pathogen vibrio cholerae?
a immunity to cholera after vaccination is short lived, lasting less than two years after
vaccination in 50% of people.
b_ up to 98% of people infected with vibrio cholerae are symptomless carriers.
c_ cholera rapidly kills up to 50% of people with symptoms if they are not treated.
d ze rehydration therapy successfully treats about 99% of people with symptoms of
cholera.

38 which row shows how penicillin kills bacteria?
| | process inhibited by penicillin effect on bacteria
a formation of water enters and
peptidoglycan cross-links bacteria burst
b breakdown of water enters and
peptidoglycan cross-links bacteria burst
cc formation of water leaves and
peptidoglycan cross-links bacteria dehydrate
d breakdown of water leaves and
peptidoglycan cross-links bacteria dehydrate

39 in the hybridoma method, what is grown by cell culture to produce monoclonal antibodies?
a antigens
b_ clones
c lymphocytes
d_ myeloma cells

40 which type of immunity does a baby have at birth?
a active artificial
b active natural
c passive artificial
d passive natural

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