Cambridge A Level Biology 9700 — 2015 May/June Paper 1 · Variant 1

Question 1

1 What are the appropriate units for measuring diameters of alveoli, diameters of white blood cells and the width of cell walls? diameters of diameters of width of alveoli white blood cells cell walls A mm µm µm B µm mm µm C µm µm nm D mm mm nm

Accepted Answer

C

Question 2

2 The diagram shows a high-power drawing of a bacterium. capsule cell wall cell membrane ribosome DNA Which three components are found in both this bacterium and an animal cell? A capsule, cell membrane and cell wall B capsule, DNA and ribosome C cell membrane, cell wall and DNA D cell membrane, DNA and ribosome

Accepted Answer

D

Question 3

3 The diagram shows a stage micrometer scale on which the small divisions are 0.1 mm. It is viewed through an eyepiece containing a graticule. 0 10 20 30 40 50 60 70 80 90 100 The stage micrometer scale is replaced by a slide of a plant cell. 0 10 20 30 40 50 60 70 80 90 100 What is the width of a chloroplast? A 0.5 mm B 10 µm C 50 µm D 100 µm

Accepted Answer

B

Question 4

4 Which structures are found in typical eukaryotic cells? 1 70S ribosomes 2 80S ribosomes 3 linear DNA (chromosomes) 4 circular DNA A 1, 2, 3 and 4 B 1, 2 and 3 only C 1 and 4 only D 2 and 3 only

Accepted Answer

A

Question 5

5 What is the function of the nucleolus? A The formation and breakdown of the nuclear envelope. B The formation of rough endoplasmic reticulum. C The synthesis of ribosomal proteins. D The synthesis of rRNA.

Accepted Answer

D

Question 6

6 The electronmicrograph shows a cell. ×5700 What is the actual diameter of the nucleus? A 0.6 µm B 6 µm C 35 µm D 350 µm

Accepted Answer

B

Question 7

7 A student carried out four tests for biological molecules on a solution. The observations are shown in the table. test for biological observation molecules iodine solution orange biuret purple Benedict’s orange emulsion cloudy Which molecules may be present in this solution? A glucose, starch, protein B lipid, protein, glucose C protein, starch, sucrose D starch, protein, lipid

Accepted Answer

B

Question 8

8 The diagrams show different types of bond found in biological molecules. 1 2 3 O NH O CH2 S S CH2 C N H 4 5 NH2 + O– O C CH2 C C CH2 C C O O C O C Which combination of bonds could not be found in a protein with a tertiary structure? A 1, 2, 3 and 4 B 1, 2 and 4 only C 3 and 5 D 5 only

Accepted Answer

D

Question 9

9 Which row shows the correct match between the descriptions of biological molecules and where they are found? 1 a linear polymer of 1,4 linked β-glucose molecules 2 a bipolar, phosphate containing molecule 3 a highly branched polymer of 1,4 and 1,6 linked α-glucose molecules 1 2 3 A eukaryote and cell surface forming storage prokaryote cell walls membranes of both granules in the cells eukaryotes and of prokaryotes prokaryotes B eukaryote cell walls cell surface forming storage membranes of both granules in the cells eukaryotes and of some eukaryotes prokaryotes C eukaryote cell walls cell surface forming starch membranes of both grains in the cells of eukaryotes and all eukaryotes prokaryotes D forms storage prokaryote cell walls eukaryote cell walls granules in the cells of eukaryotes

Accepted Answer

B

Question 10

10 Which is the correct description for the structure of amylose and cellulose? amylose cellulose A α-glucose β-glucose 180° rotation no rotation 1,4 and 1,6 linkages 1,4 linkages B α-glucose β-glucose no rotation 180° rotation 1,4 linkages 1,4 linkages C α-glucose α-glucose no rotation 180° rotation 1,4 linkages 1,4 and 1,6 linkages D β-glucose α-glucose no rotation 180° rotation 1,4 linkages 1,4 linkages

Accepted Answer

B

Question 11

11 Which description is correct? A A collagen molecule has a high proportion of the amino acid glycine, which has a very small side chain. B A group of three collagen fibres forms a strong, insoluble coiled structure termed a triple helix. C Each of the collagen polypeptides in a collagen molecule has a regular spiral arrangement of many alpha helices. D Peptide bonds are present between amino acids of the same polypeptide and between the different polypeptides forming the collagen molecule.

Accepted Answer

A

Question 12

12 Polar molecules form hydrogen bonds with each other. Which properties of water result from its molecules being polar? 1 good solvent 2 high specific heat capacity 3 high surface tension 4 cohesive A 1, 2, 3 and 4 B 1, 2 and 3 only C 1, 2 and 4 only D 3 and 4 only

Accepted Answer

A

Question 13

13 Which statements about the effect of all enzyme inhibitors are correct? 1 change the shape of the active site 2 denature the enzyme 3 reduce the rate of the enzyme-catalysed reaction A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 3 only

Accepted Answer

D

Question 14

14 The graphs show the rate of reaction of an enzyme-catalysed reaction. Which graph shows the effect of increasing the concentration of the substrate at two different concentrations of a competitive inhibitor? key no inhibitor low concentration of inhibitor high concentration of inhibitor A B rate of rate of reaction reaction substrate substrate concentration concentration C D rate of rate of reaction reaction substrate substrate concentration concentration

Accepted Answer

B

Question 15

15 Which type of cell has a large number of glycoproteins on the cell surface membrane? A ciliated cell B goblet cell C lymphocyte D red blood cell

Accepted Answer

C

Question 16

16 The diagram shows the transport of ions across the cell surface membrane. Inside the cell there is a low concentration of sodium ions (Na+) and a high concentration of potassium ions (K+). Outside the cell there is a low concentration of K+ and a high concentration of Na+. The carrier molecule is a pump which exchanges Na+ for K+. inside cell 2 1 cell surface membrane 4 carrier 3 molecule outside cell Which ionic movements are represented by the arrows? active transport active transport diffusion of Na+ diffusion of K+ of K+ of Na+ A 2 3 1 4 B 2 3 4 1 C 3 2 1 4 D 3 2 4 1

Accepted Answer

A

Question 17

17 Which set of factors will produce the most fluid cell surface membrane? a decrease in A • distance between phospholipid molecules • proportion of short fatty acid chains B • distance between phospholipid molecules • temperature C • proportion of phospholipids with saturated fatty acid chains • proportion of long fatty acid chains D • proportion of phospholipids with unsaturated fatty acid chains • temperature

Accepted Answer

C

Question 18

18 The graphs show various measurements taken from metaphase of mitosis onwards. The graphs are to scale when compared to one another. X distance time Y distance time Z distance time Which row correctly identifies each graph? X Y Z A distance between poles distance between distance of centromere of spindle sister chromatids from pole of spindle B distance between poles distance of centromere distance between of spindle from pole of spindle sister chromatids C distance of centromere distance between distance between from pole of spindle poles of spindle sister chromatids D distance of centromere distance between distance between poles from pole of spindle sister chromatids of spindle

Accepted Answer

C

Question 19

19 A scientist counted 22 chromosomes in each of the root cells of a xerophytic plant. What is the diploid and haploid number of chromosomes for this species? diploid haploid number number A 11 22 B 22 11 C 22 44 D 44 22

Accepted Answer

B

Question 20

20 Which row shows two pairs of nucleotides formed during transcription? first base pair transcribed second base pair transcribed number of number of bases bases hydrogen bonds hydrogen bonds A AU 2 CG 2 B AU 2 CG 3 C AU 2 TU 2 D AU 3 CG 2

Accepted Answer

B

Question 21

21

Which row correctly identifies the features of DNA and RNA molecules?

DNA and RNA
contain both purine

DNA and RNA
both contain a

hydrogen bonds form
between bases in

and pyrimidine bases | pentose sugar some RNA
A v v v
B v v x
Cc v x v
D x v x

key
/ = correct statement

X = incorrect statement

Accepted Answer

A

Question 22

22 Two polynucleotide strands make up a DNA molecule. What is a correct description? A The percentage of cytosine is 50% of that of guanine in the whole molecule. B The percentage of cytosine is the same as that of guanine in each strand. C The percentage of cytosine is the same as that of guanine in the whole molecule. D The percentage of cytosine is the same in each strand of the molecule.

Accepted Answer

C

Question 23

23 The diagram shows transverse sections of two plant structures. 1 2 3 4 Which row shows the correct labels? 1 2 3 4 A cuticle phloem xylem pith B cuticle xylem phloem cortex C epidermis phloem xylem cortex D epidermis xylem phloem pith

Accepted Answer

C

Question 24

24 A tissue composed of plasmolysed plant cells was put into distilled water. The graph shows how the mean cell volume changes with time. X mean cell volume 0 time What is the cause of the plateau at X? 1 water potential in the plant cell has become more negative 2 cells have become fully turgid 3 no net movement of water into cells A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Accepted Answer

D

Question 25

25 The diagram shows a vascular bundle from the stem of a plant. 3 2 1 Which row describes the functions of the labelled cells? transports transports stores sucrose ions starch A 1 2 3 B 2 1 3 C 2 3 1 D 3 1 2

Accepted Answer

B

Question 26

26 Which changes to the water potential and the volume of liquid in the phloem occur when amino acids are moved into a sink from phloem sieve tubes? water potential volume of liquid in a phloem in phloem sieve sieve tube tubes A higher decreased B higher increased C lower decreased D lower increased

Accepted Answer

A

Question 27

27 The graph shows the oxygen dissociation curves for haemoglobin from three different animals. 100 X 80 Y percentage Z 60 saturation of haemoglobin with oxygen 40 20 0 0 2 4 6 8 10 12 14 partial pressure of oxygen / kPa Which of the haemoglobins, X, Y or Z, would be present in each of the animals 1, 2 or 3? 1 an adult human 2 a fish living in water that has a very low oxygen concentration 3 a very active mammal whose tissues have a much higher rate of respiration than an adult human 1 2 3 A X Y Z B Y X Z C Y Z X D Z Y X

Accepted Answer

B

Question 28

28 What explains how the uptake of oxygen is maximised as blood passes through the capillaries of the lungs? A Each haemoglobin molecule can temporarily bind to four oxygen atoms. B Oxyhaemoglobin formation increases the capacity of red blood cells to transport oxygen. C The binding of the first oxygen molecule to haemoglobin decreases the molecule’s affinity for binding other oxygen molecules. D The dissociation of carbon dioxide from carboxyhaemoglobin allows more haemoglobin to be available for oxygen binding.

Accepted Answer

B

Question 29

29 What happens after carbonic anhydrase has catalysed a reaction involved in the transport of carbon dioxide? A the dissociation of oxyhaemoglobin to haemoglobin and oxygen B the formation of carbaminohaemoglobin from carbon dioxide and haemoglobin C the formation of carbon dioxide and water from carbonic acid D the formation of oxyhaemoglobin from haemoglobin and oxygen

Accepted Answer

A

Question 30

30 The diagram shows a section through the heart and the associated blood vessels. What is correct for the flow of blood through the heart? 1 4 2 3 A 1  →  2  →  3  →  4 B 2  →  1  →  3  →  4 C 3  →  4  →  1  →  2 D 4  →  3  →  2  →  1

Accepted Answer

B

Question 31

31 Which row shows a function of each of the named tissues in the gas exchange system? cartilage ciliated epithelium smooth muscle elastic fibres A keep the move mucus out change the allows alveoli to airways open of the airways diameter of the expand during bronchioles breathing in B prevent choking secrete mucus contracts to helps to support increase air flow the trachea C prevent the keep a layer of trap bacteria and cause elastic recoil trachea collapsing mucus lining the dirt in air when breathing out when coughing air ways D support the small trap bacteria and control the flow of allows stretching bronchioles dirt in air air to and from the of trachea for alveoli movement

Accepted Answer

A

Question 32

32 The graph shows the results of a study to determine whether there is a link between the number of cigarettes smoked by a mother and the birth weight of her baby. birth weight of babies / kg 0 10 20 30 40 50 number of cigarettes smoked by mother each day Which conclusions can be drawn from this graph? 1 As the number of cigarettes smoked increases, the weight of the baby always decreases. 2 Factors, other than smoking, affect the birth weight of a baby. 3 Nicotine, tar and carbon monoxide slow the growth of an unborn baby. 4 The majority of all smokers smoke between 10 and 35 cigarettes per day. A 1, 2 and 3 B 2, 3 and 4 C 2 only D 3 only

Accepted Answer

C

Question 33

33 What is a feature of coronary bypass surgery? A A section of a healthy vein or artery is attached to the aorta at one end and a coronary artery at the other end to bypass diseased sections of coronary artery. B A section of healthy vein or artery is used to bypass the diseased section of aorta in the region where the branches to the coronary arteries occur. C Blockages in coronary arteries with atherosclerosis are cleared surgically by temporarily using an artificial heart to re-route blood and bypass the heart. D The section of diseased coronary artery is removed and then replaced by using a section of a healthy vein or artery of a similar diameter.

Accepted Answer

A

Question 34

34 The first column in the table contains statements about disease. Columns headed 1-4 represent
four different named diseases.

statements 1

infectious disease v v v

can be treated with antibiotics v v key
caused by a virus v ¥ =true
degeneration of lung tissue v v

What is the correct set of column headings for the table above?

1 2 3 4
A bronchitis measles TB smallpox
B emphysema HIV/AIDS cholera TB
Cc emphysema measles cholera lung cancer
D lung cancer HIV/AIDS measles TB

Accepted Answer

B

Question 35

35 Which row is correct for malaria? nature of disease method of transmission pathogen A infectious insect vector species of Plasmodium B infectious water-borne species of Vibrio C non-infectious insect vector species of Plasmodium D non-infectious water-borne species of Vibrio

Accepted Answer

A

Question 36

36 During an outbreak of a very infectious disease, vulnerable people need immediate protection. Which type of immunity would be given to these people? natural artificial active A B passive C D

Accepted Answer

D

Question 37

37 Which cells become memory cells in the immune response? 1 B-lymphocytes 2 T-lymphocytes 3 phagocytes A 1, 2 and 3 B 1 and 2 only C 1 only D 2 only

Accepted Answer

B

Question 38

38 Which soil would have the smallest number of denitrifying bacteria? A compressed agricultural soil B poorly drained forest soil C water-logged clay soil D well-aerated garden soil

Accepted Answer

D

Question 39

39 In an ecosystem, at which stage is most energy lost? A sunlight → trophic level 1 B trophic level 1 → trophic level 2 C trophic level 2 → trophic level 3 D trophic level 3 → trophic level 4

Accepted Answer

A

Question 40

40 Two species of animal are found in the same area of forest and grassland. In the spring and summer they eat the same plant food. However, in the autumn and winter one eats nuts in the forest and the other eats roots on the grassland. Both species are preyed upon by the same predator. Numbers of root-eating animals are reduced most by this, but they recover faster since they reproduce faster. What can be concluded about these two species of animals? 1 They are part of the same community. 2 They are at different trophic levels. 3 They occupy different habitats. 4 They have different niches. A 1, 2 and 4 B 2, 3 and 4 C 1 and 2 only D 1 and 4 only

Accepted Answer

D

Question paper20 pages

Mark scheme2 pages

Questions as text

Q1 · What are the appropriate units for measuring diameters of alveoli, diameters of white…

Q2 · The diagram shows a high-power drawing of a bacterium

Q3 · The diagram shows a stage micrometer scale on which the small divisions are 0.1 mm

Q4 · Which structures are found in typical eukaryotic cells?

Q5 · What is the function of the nucleolus?

Q6 · The electronmicrograph shows a cell

Q7 · A student carried out four tests for biological molecules on a solution

Q8 · The diagrams show different types of bond found in biological molecules

Q9 · Which row shows the correct match between the descriptions of biological molecules and…

Q10 · Which is the correct description for the structure of amylose and cellulose?

Q11 · Which description is correct?

Q12 · Polar molecules form hydrogen bonds with each other

Q13 · Which statements about the effect of all enzyme inhibitors are correct?

Q14 · The graphs show the rate of reaction of an enzyme-catalysed reaction

Q15 · Which type of cell has a large number of glycoproteins on the cell surface membrane?

Q16 · The diagram shows the transport of ions across the cell surface membrane

Q17 · Which set of factors will produce the most fluid cell surface membrane?

Q18 · The graphs show various measurements taken from metaphase of mitosis onwards

Q19 · A scientist counted 22 chromosomes in each of the root cells of a xerophytic plant

Q20 · Which row shows two pairs of nucleotides formed during transcription?

Q21 · Which row correctly identifies the features of DNA and RNA molecules?

Q22 · Two polynucleotide strands make up a DNA molecule

Q23 · The diagram shows transverse sections of two plant structures

Q24 · A tissue composed of plasmolysed plant cells was put into distilled water

Q25 · The diagram shows a vascular bundle from the stem of a plant

Q26 · Which changes to the water potential and the volume of liquid in the phloem occur when…

Q27 · The graph shows the oxygen dissociation curves for haemoglobin from three different…

Q28 · What explains how the uptake of oxygen is maximised as blood passes through the…

Q29 · What happens after carbonic anhydrase has catalysed a reaction involved in the transport…

Q30 · The diagram shows a section through the heart and the associated blood vessels

Q31 · Which row shows a function of each of the named tissues in the gas exchange system?

Q32 · The graph shows the results of a study to determine whether there is a link between the…

Q33 · What is a feature of coronary bypass surgery?

Q34 · The first column in the table contains statements about disease

Q35 · Which row is correct for malaria?

Q36 · During an outbreak of a very infectious disease, vulnerable people need immediate…

Q37 · Which cells become memory cells in the immune response?

Q38 · Which soil would have the smallest number of denitrifying bacteria?

Q39 · In an ecosystem, at which stage is most energy lost?

Q40 · Two species of animal are found in the same area of forest and grassland

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