Cambridge A Level Biology 9700 — 2014 May/June Paper 1 · Variant 2

Question 1

1 At approximately which magnification is light microscopy not suitable because the resolution becomes too low? A ×100 B ×200 C ×400 D ×1500

Accepted Answer

D

Question 2

2 The diagram shows a stage micrometer viewed with an eyepiece graticule scale, using a magnification of ×400. 0.1mm 0 10 20 30 40 50 60 70 80 90 100 Using the same magnification, a chloroplast is measured and found to be 4 eyepiece graticule divisions long. How long is the chloroplast? A 1.0 × 101 µm B 4.0 × 102 µm C 2.5 × 10–1 µm D 2.5 × 10–2 µm

Accepted Answer

A

Question 3

3 Which organelle does not contain a partially permeable membrane? A Golgi apparatus B lysosome C mitochondrion D ribosome

Accepted Answer

D

Question 4

4 The diagram shows an electron micrograph of a plant cell. X Y Z What do structures X, Y and Z contain? X Y Z A air starch DNA and RNA B cell sap chlorophyll protein C mineral ions starch DNA and RNA D water mineral ions starch

Accepted Answer

C

Question 5

5 An amino acid enters a cell and is then used to synthesise an enzyme secreted by the cell. What is the sequence of cell structures involved in the synthesis of the enzyme? first last A endoplasmic Golgi ribosome exocytotic reticulum apparatus vesicle B endoplasmic ribosome Golgi cell surface reticulum apparatus membrane C ribosome endoplasmic Golgi exocytotic reticulum apparatus vesicle D ribosome Golgi endoplasmic cell surface apparatus reticulum membrane

Accepted Answer

C

Question 6

6 The diagram shows some similarities between chloroplasts, mitochondria and typical prokaryotes. 1 2 3 4 5 Which row is correct? 1 2 3 4 5 A chloroplasts 70S ribosomes prokaryotes 70S ribosomes mitochondria B chloroplasts 70S ribosomes prokaryotes 80S ribosomes mitochondria C mitochondria 70S ribosomes chloroplasts 80S ribosomes prokaryotes D mitochondria 80S ribosomes chloroplasts 80S ribosomes prokaryotes

Accepted Answer

A

Question 7

7 Which shows the basic unit of glycogen? A B CH2OH CH2OH H C O OH H C O H H H C C C C OH H OH H HO C C H HO C C OH H OH H OH C D H CH2OH H C O CH2OH HO C O OH H H C C C C H OH OH H HO C C OH H C C H OH H H OH

Accepted Answer

B

Question 8

8 Four sugar solutions were tested with Benedict’s solution. The table shows the colour of the solutions after testing. solution colour 1 green 2 blue 3 brick red 4 yellow What is the best interpretation of the results? solution 1 solution 2 solution 3 solution 4 A 0.05% reducing 0.5% non-reducing 1.0% reducing 0.1% reducing sugar sugar sugar sugar B 0.5% reducing 0.0% reducing 1.0% reducing 0.1% reducing sugar sugar sugar sugar C 1.0% reducing 1.0% non-reducing 1.5% reducing 0.5% reducing sugar sugar sugar sugar D 0.05% non-reducing 0.5% reducing 1.0% non-reducing 0.1% non-reducing sugar sugar sugar sugar

Accepted Answer

A

Question 9

9 Which features adapt a cellulose molecule for its function? 1 Long chains of glucose molecules coil into a helix. 2 Many hydrogen bonds form between adjacent chains. 3 It is insoluble in water. A 1, 2 and 3 B 1 and 3 only C 2 and 3 only D 2 only

Accepted Answer

C

Question 10

10 The structure of phospholipids and triglycerides include the following. 1 glycerol linked to fatty acids 2 hydrophobic fatty acid chains 3 saturated fatty acid chains Which structures enable the formation of a lipid bilayer in cell surface membranes? A 1 and 2 B 1 and 3 C 2 and 3 D 2 only

Accepted Answer

D

Question 11

11 Which molecule contains a glycosidic bond? A B H H O OH HO CH2 C C H C O C R H O O N CH3 CH2 C C H H C O C R H O O N CH3 C C H H C O C R O N H H H C D H CH2OH N O N H O H C H C O CH2OH H O C C C C H N C C C C H C N H N O OH H O H OH CH2OH HO N C C N C C C C O H N H OH OH H H

Accepted Answer

C

Question 12

12 The diagrams show the structures of two amino acids, each of which has two carboxylic acid (–COOH) groups. 1 3 4 H2N CH COOH H2N CH COOH CH2 CH2 COOH 2 CH2 COOH 5 A peptide bond is formed between the two amino acids. Which groups form the peptide bond? A 1 and 4 B 1 and 5 C 2 and 3 D 2 and 5

Accepted Answer

A

Question 13

13 The drug ritonavir is sometimes used in the treatment of HIV / AIDS. Ritonavir consists of three amino acids and is a competitive inhibitor of HIV protease. HIV causes this protease to be made inside human cells. Ritonavir produces many side effects as it interferes with many metabolic processes in human cells. Which statements about ritonavir are correct? 1 Ritonavir has a shape complementary to the active site of HIV protease. 2 Ritonavir will enter human cells directly through the lipid bilayer and not require any transport proteins. 3 Ritonavir is likely to inhibit many of the enzymes of human cells. 4 Complete hydrolysis of ritonavir would require the addition of three water molecules. A 1, 2 and 3 B 1 and 3 only C 2 and 4 D 3 and 4

Accepted Answer

B

Question 14

14 The diagram shows the fluid mosaic model of a section of a cell surface membrane. 2 1 3 What is the role of each of the components labelled 1 to 3? 1 2 3 A antigen chemical receptor allow lipid soluble molecules to pass through B barrier to polar molecules stabilise the membrane antigen C chemical receptor allow lipid soluble regulate the fluidity molecules to pass through of the membrane D stabilise the membrane control the fluidity barrier to polar molecules of the membrane

Accepted Answer

A

Question 15

15 Proteins in the cell surface membranes of human cells and mouse cells were labelled with red and green fluorescent dyes respectively. When a human cell and a mouse cell were fused together the red and green fluorescent labels were at first found in different regions of the cell surface membrane of the hybrid cell, but after 40 minutes they were evenly distributed in the entire cell surface membrane. What explains this observation? A All protein molecules in the cell surface membrane are fixed to structures within the cell, but phospholipid molecules move freely between them. B Groups of protein and phospholipid molecules in the cell surface membrane are attached to each another and move together. C Only protein molecules in the outer layer of the cell surface membrane can move freely between phospholipid molecules. D Protein molecules in the outer layer of the cell surface membrane and those which span the bilayer can move freely between phospholipid molecules.

Accepted Answer

D

Question 16

16 The diagram shows a plant cell. The plant cell is put into a solution with a water potential less negative than the cell contents. What will happen to the appearance of the cell? A B C D

Accepted Answer

C

Question 17

17 The cell cycle includes mitosis. Which are features of nuclear division? 1 forms cells of equal size to the parent cell 2 forms genetically identical cells 3 semi-conservative replication of DNA A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 only

Accepted Answer

D

Question 18

18 Which is the correct statement concerning cell and nuclear division? A Haploid eukaryotes can reproduce by mitosis whereas diploid eukaryotes can reproduce by mitosis or meiosis. B Just before prophase, the mass of DNA is double the normal mass. Following anaphase, this mass is reduced by half and following cytokinesis this mass halves again. C Mutagens can cause mutations whereas carcinogens can cause cancer. This means that all mutagens are carcinogenic. D Some of the roles of mitosis are growth, asexual reproduction, cell repair following tissue damage and cell replacement.

Accepted Answer

A

Question 19

19 Diploid (2n) organisms that reproduce sexually produce haploid (n) gametes. Some plants, such as wheat, can produce diploid or haploid gametes. These gametes can fertilise other diploid or haploid gametes. Which statements are correct for plants like these? 1 Diploid gametes may be produced by a fault in the reduction division (meiosis). 2 The offspring will always show an increased chromosome number. 3 The offspring could be either 2n, 3n or 4n. 4 The chromosome number could, in theory, increase with each generation. A 1, 2 and 3 B 1, 2 and 4 C 1, 3 and 4 D 2, 3 and 4

Accepted Answer

C

Question 20

20 Which nucleic acid bases are pyrimidines? A adenine and guanine B adenine, cytosine and thymine C cytosine, thymine and uracil D guanine, cytosine and uracil

Accepted Answer

C

Question 21

21 What is the correct sequence for the processes involved in the formation of an enzyme in a cell? A transcription → condensation → translation → ionic bonding B translation → hydrogen bonding → transcription → condensation C transcription → translation → condensation → ionic bonding D translation → transcription → ionic bonding → hydrogen bonding

Accepted Answer

C

Question 22

22 A short piece of DNA fifteen base pairs long was analysed to find the number of nucleotide bases in each of the polynucleotide strands. Some of the results are shown below. number of nucleotide bases A C G T strand 1 6 3 strand 2 4 How many nucleotides containing adenine (A) were present in strand 2? A 2 B 3 C 4 D 6

Accepted Answer

A

Question 23

23 Which feature of xylem vessel elements helps adhesion during transpiration? A lignin forms an incomplete secondary wall B new vessels carry extra water as the plants grow C there are no cross walls between vessel elements D the vessel elements form a narrow tube

Accepted Answer

D

Question 24

24 The diagram represents part of the phloem pathway, with adjacent cells, from leaf to root in a plant. 2 leaf cell 1 chloroplast parenchyma cell nucleus companion cell root cell Which process is occurring between 1 to 2 and what is the effect on the water potential at 2? process from 1 to 2 water potential at 2 A active transport of sucrose becomes less negative B active transport of sucrose becomes more negative C diffusion of sucrose becomes less negative D diffusion of sucrose becomes more negative

Accepted Answer

B

Question 25

25 Which xerophytic adaptations reduce the water potential gradient? 1 rolled leaves 2 hairy leaves 3 sunken stomata 4 fewer stomata 5 fleshy leaves A 1, 2, 3, 4 and 5 B 1, 2 and 3 only C 1, 3 and 4 only D 2 and 5 only

Accepted Answer

B

Question 26

26 What is not a factor influencing blood pressure? A the diameter of the blood vessels B the number of red blood cells in circulation C the systolic pressure of the heart ventricles D the volume of blood returning to the heart each heart beat

Accepted Answer

B

Question 27

27 Which of the following are found in blood and lymph and tissue fluid? 1 carbon dioxide 2 fatty acids 3 white blood cells 4 proteins 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 28

28 The graph shows the percentage saturation of haemoglobin with oxygen at different partial pressures of oxygen and two different concentrations of carbon dioxide. 100 low concentration CO2 75 % saturation haemoglobin 50 high concentration CO2 of haemoglobin with oxygen 25 0 2 4 6 8 10 12 14 partial pressure of O2 / kPa What is the effect of increasing the concentration of carbon dioxide? A It increases the affinity of haemoglobin for oxygen at respiring tissues. B It increases the dissociation of haemoglobinic acid inside red blood cells. C It increases the dissociation of oxygen from haemoglobin at respiring tissues. D It increases the inhibition of carbonic anhydrase enzyme in red blood cells.

Accepted Answer

C

Question 29

29 Some babies are born with a hole between the right and left atria. These babies are found to have an increased number of red blood cells. What is the reason for this increase? A More blood is needed because it is pumped faster. B More blood is needed because the pressure is lower. C Their haemoglobin has a higher affinity for oxygen. D There is less oxygen available to the newly born baby.

Accepted Answer

D

Question 30

30 In the lungs, oxygen and carbon dioxide pass through cell membranes by diffusion. Which row is correct? number of cell membranes diffused through by oxygen from air carbon dioxide to air A 3 2 B 3 2 or 3 C 5 4 D 5 4 or 5

Accepted Answer

D

Question 31

31 Which describes how substances in cigarette smoke increase the risk of developing atherosclerosis? 1 Carbon monoxide damages the endothelium of the arteries. 2 Nicotine makes platelets sticky. 3 Nicotine stimulates the release of adrenaline. A 1, 2 and 3 B 1 and 3 only C 1 only D 2 only

Accepted Answer

D

Question 32

32 Which flow diagram correctly describes the effect of tar entering the lungs? carcinogens A come into mutation uncontrolled cell → → contact with occurs division DNA mucus goblet cells phagocytes B accumulates secrete more → → attracted by causing mucus inflammation infection mucus phagocytes elastase C accumulates → attracted by → destroys the causing infection inflammation alveolar walls phagocytes causes D mutation → attracted by → irritation and occurs inflammation coughing

Accepted Answer

A

Question 33

33 Which could directly reduce the surface area available for gas exchange in human lungs? 1 emphysema 2 lung cancer 3 smoking A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Accepted Answer

B

Question 34

34 The malarial parasite, Plasmodium, infects red blood cells and breaks down haemoglobin. Free haem groups are toxic to Plasmodium and the parasite converts them into non-toxic, crystalline haematozoin, using an enzyme, HDP, which is found in all species of Plasmodium. What will be the long term result of giving patients with malaria a drug which inhibits HDP? A a decreased concentration of free haem groups in infected red blood cells B a decreased concentration of haemoglobin in infected red blood cells C more rapid reproduction of some species of Plasmodium in infected red blood cells D slower reproduction of all species of Plasmodium in infected red blood cells

Accepted Answer

D

Question 35

35 During a primary immune response, the following events occur. 1 Some B-lymphocytes form plasma cells. 2 B-lymphocytes with the specific cell surface receptors divide repeatedly by mitosis. 3 Specific antibody is produced. 4 T-helper cells secrete cytokines. 5 T-helper cells identify a specific antigen. In which order will the events occur? A 2 → 1 → 4 → 3 → 5 B 2 → 4 → 3 → 1 → 5 C 5 → 4 → 2 → 1 → 3 D 5 → 4 → 3 → 1 → 2

Accepted Answer

C

Question 36

36 Which statement concerning the defence in the body against infectious disease is not correct? A Antibodies against specific antigens are produced by plasma cells in passive immunity, but the protection is short-lived as no memory cells are produced. B A specific immune response involves activation of B-lymphocytes and T-lymphocytes following recognition of, and binding to, a specific antigen. C Following invasion by microorganisms, natural active immunity can be gained by initiating an immune response. D Lysosomes fuse with vacuoles that have been formed by phagocytes and which contain invading microorganisms.

Accepted Answer

A

Question 37

37 An antiserum to a snake toxin can be obtained by injecting the toxin into a horse. The antiserum is made from blood plasma taken from the horse a few weeks later. The antiserum is injected into a person who has been bitten by the same species of snake. Which type of immunity occurs as a result of using this antiserum? A artificial active B artificial passive C natural active D natural passive

Accepted Answer

B

Question 38

38 The flow of nutrients in an ecosystem is shown in the diagram. Which letter represents decomposers? producers D A C B

Accepted Answer

D

Question 39

39 An insect eats only the leaves of grass. This insect is eaten by carnivorous beetles. Which ecological terms are described in this information about the insect? 1 habitat 2 niche 3 trophic level A 1, 2 and 3 B 2 and 3 only C 2 only D 3 only

Accepted Answer

D

Question 40

40 A gardener has a waterlogged garden showing poor growth. He decides to drain it in an attempt to reduce the numbers of some harmful bacteria. Which type of bacteria would he be attempting to reduce in number? A decomposing B denitrifying C nitrifying D nitrogen fixing

Accepted Answer

B

Question paper16 pages

Mark scheme2 pages

Questions as text

Q1 · At approximately which magnification is light microscopy not suitable because the…

Q2 · The diagram shows a stage micrometer viewed with an eyepiece graticule scale, using a…

Q3 · Which organelle does not contain a partially permeable membrane?

Q4 · The diagram shows an electron micrograph of a plant cell

Q5 · An amino acid enters a cell and is then used to synthesise an enzyme secreted by the cell

Q6 · The diagram shows some similarities between chloroplasts, mitochondria and typical…

Q7 · Which shows the basic unit of glycogen?

Q8 · Four sugar solutions were tested with Benedict’s solution

Q9 · Which features adapt a cellulose molecule for its function?

Q10 · The structure of phospholipids and triglycerides include the following

Q11 · Which molecule contains a glycosidic bond?

Q12 · The diagrams show the structures of two amino acids, each of which has two carboxylic…

Q13 · The drug ritonavir is sometimes used in the treatment of HIV / AIDS

Q14 · The diagram shows the fluid mosaic model of a section of a cell surface membrane

Q15 · Proteins in the cell surface membranes of human cells and mouse cells were labelled with…

Q16 · The diagram shows a plant cell

Q17 · The cell cycle includes mitosis

Q18 · Which is the correct statement concerning cell and nuclear division?

Q19 · Diploid (2n) organisms that reproduce sexually produce haploid (n) gametes

Q20 · Which nucleic acid bases are pyrimidines?

Q21 · What is the correct sequence for the processes involved in the formation of an enzyme in…

Q22 · A short piece of DNA fifteen base pairs long was analysed to find the number of…

Q23 · Which feature of xylem vessel elements helps adhesion during transpiration?

Q24 · The diagram represents part of the phloem pathway, with adjacent cells, from leaf to root…

Q25 · Which xerophytic adaptations reduce the water potential gradient?

Q26 · What is not a factor influencing blood pressure?

Q27 · Which of the following are found in blood and lymph and tissue fluid?

Q28 · The graph shows the percentage saturation of haemoglobin with oxygen at different partial…

Q29 · Some babies are born with a hole between the right and left atria

Q30 · In the lungs, oxygen and carbon dioxide pass through cell membranes by diffusion

Q31 · Which describes how substances in cigarette smoke increase the risk of developing…

Q32 · Which flow diagram correctly describes the effect of tar entering the lungs?

Q33 · Which could directly reduce the surface area available for gas exchange in human lungs?

Q34 · The malarial parasite, Plasmodium, infects red blood cells and breaks down haemoglobin

Q35 · During a primary immune response, the following events occur

Q36 · Which statement concerning the defence in the body against infectious disease is not…

Q37 · An antiserum to a snake toxin can be obtained by injecting the toxin into a horse

Q38 · The flow of nutrients in an ecosystem is shown in the diagram

Q39 · An insect eats only the leaves of grass

Q40 · A gardener has a waterlogged garden showing poor growth

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