Cambridge A Level Biology 9700 — 2018 May/June Paper 1 · Variant 3

Question 1

1 Which steps are needed to find the actual width of a xylem vessel viewed in transverse section using a ×10 objective lens? 1 Convert from mm to µm by multiplying by 10–3. 2 Calibrate the eyepiece graticule using a stage micrometer on ×4 objective lens. 3 Measure the width of the xylem vessel using an eyepiece graticule. 4 Multiply the number of eyepiece graticule units by the calibration of the eyepiece graticule. A 1, 2, 3 and 4 B 1 and 2 only C 2, 3 and 4 only D 3 and 4 only

Accepted Answer

D

Question 2

2 The diagram shows functions of four cell structures, W, X, Y and Z. W makes glycolipid Z transports X makes function protein protein Y makes lipid Which row correctly matches the cell structure with the letter representing a function? rough smooth Golgi body ribosome endoplasmic endoplasmic reticulum reticulum A W X Z Y B X Z Y W C Y W X Z D Z Y W X

Accepted Answer

A

Question 3

3 Which cell structures produce ATP? 1 chloroplasts 2 mitochondria 3 nucleus A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Accepted Answer

B

Question 4

4 When mucus is secreted from a goblet cell these events take place. 1 addition of carbohydrate to protein 2 fusion of the vesicle with the cell surface membrane 3 secretion of a glycoprotein 4 separation of a vesicle from the Golgi body What is the sequence in which these events take place? A 1 → 4 → 2 → 3 B 1 → 4 → 3 → 2 C 4 → 1 → 2 → 3 D 4 → 1 → 3 → 2

Accepted Answer

A

Question 5

5 Which row could be correct for a virus?

carbohydrate DNA phospholipid lipid protein RNA
A J J Jv J Jv J
B v x Jv x x v
Cc x J x x x J
D x Jv x x v x
key
v = present

X =not present

Accepted Answer

D

Question 6

6 Which size range would include most prokaryotic cells? A B C D 1 nm 100 nm 1 µm 100 µm 1 mm

Accepted Answer

B

Question 7

7 Solutions of three biological molecules are tested for sugars. The table shows the colours of the solutions after testing. boiled with hydrochloric acid, heated with Benedict’s solution neutralised, then heated with solution Benedict’s solution 1 blue orange 2 green green 3 orange red Which solutions contained glucose before testing? A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Accepted Answer

D

Question 8

8 A solution containing equal masses of amylose and amylopectin is completely hydrolysed. Which molecules will be found after the hydrolysis? A α-glucose only B β-glucose only C equal masses of α-glucose and β-glucose D more α-glucose than β-glucose

Accepted Answer

A

Question 9

9 Which molecules contain the following bonds? ester hydrogen disulfide A amylase haemoglobin catalase B glycerol glycogen collagen C lipids amylopectin amylose D phospholipids cellulose antibodies

Accepted Answer

D

Question 10

10 Which feature of phospholipids enables a bilayer to form? A They are insoluble in water. B They are polar molecules. C They have hydrophobic and hydrophilic components. D They may contain saturated or unsaturated fatty acids.

Accepted Answer

C

Question 11

11 Which description is correct for collagen? A A collagen molecule has a high proportion of the amino acid glycine, which has a very small R group. 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 different polypeptides forming the collagen molecule.

Accepted Answer

A

Question 12

12 Which statement about the properties of water is correct? A Bonds between hydrogen atoms cause water to have a high specific heat capacity. B The high latent heat of vaporisation of water is due to the presence of hydrogen bonds. C The high specific heat capacity of water causes cooling during evaporation. D Water can dissolve amylopectin as it has hydrophilic side chains.

Accepted Answer

B

Question 13

13 Catechol is a chemical found in a number of fruits. Catechol can be oxidised to a quinone by the enzyme catechol oxidase. Catechol oxidase is inhibited by parahyroxybenzoic acid (PHBA) which is structurally similar to catechol. Catechol oxidase is also inhibited by phenylthiourea (PTU) which binds to a copper atom in the enzyme. How do both these inhibitors reduce the enzyme activity? 1 altering the specificity of the enzyme 2 competing with substrates for the active site 3 decreasing the Vmax of the reaction A 1, 2 and 3 B 1 only C 2 only D 3 only

Accepted Answer

B

Question 14

14 Four students investigated the effect of catalase on hydrogen peroxide. Each student started a digital clock at the beginning of the experiment and stopped the clock after 25 bubbles had been counted. The time recorded on the digital clock is shown below. hundredths hours minutes seconds of a second 00 01 33 54 Which of the times recorded by the students is appropriate for this experiment? A 1.34 minutes B 1 minute 33.54 seconds C 94 seconds D 93.54 seconds

Accepted Answer

C

Question 15

15 What is the effect of an enzyme in an enzyme-catalysed reaction? A decreases the activation energy and decreases the energy yield B decreases the activation energy and has no effect on the energy yield C increases the activation energy and increases the energy yield D increases the energy yield and decreases the activation energy

Accepted Answer

B

Question 16

16 The diagram shows part of the cell surface membrane. 1 2 4 3 Which components act as antigens? A 1 and 2 B 1 and 3 C 2 and 3 D 2 and 4

Accepted Answer

A

Question 17

17 Which processes use energy in the form of ATP? 1 endocytosis 2 exocytosis 3 facilitated diffusion A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Accepted Answer

B

Question 18

18 The diagram shows a partially plasmolysed plant cell. solution X Z solution Y What is found at Z? A air B solution X C solution Y D water

Accepted Answer

C

Question 19

19 Which features of an organism are affected by a drug that stops mitosis? 1 cell repair 2 cell replacement 3 number of stem cells 4 tissue repair 5 tumour formation A 1, 2, 3, 4 and 5 B 1, 2 and 3 only C 1, 4 and 5 only D 2, 3, 4 and 5 only

Accepted Answer

D

Question 20

20 Which row shows the appearance of a chromosome at the beginning of prophase of mitosis and the number of DNA strands in the chromosome? appearance of number of one chromosome DNA strands A 2 B 4 C 1 D 2

Accepted Answer

B

Question 21

21 The graph shows measurements taken during one mitotic cell cycle. X 2 1 distance 0 5 10 15 20 25 time / minutes Which stage of mitosis begins at X and which measurements are shown by curves 1 and 2? distance between distance between stage centromeres of centromeres of beginning at X chromosomes and sister chromatids poles of spindle A anaphase 1 2 B anaphase 2 1 C metaphase 1 2 D metaphase 2 1

Accepted Answer

A

Question 22

22 The diagram shows the outline structure of two nucleotide bases which occur in DNA. This pair is held together by two hydrogen bonds, shown as dashed lines. nucleotide 2 nucleotide 1 Which row correctly identifies these two nucleotide bases? nucleotide 1 nucleotide 2 A adenine thymine B cytosine guanine C guanine cytosine D thymine adenine

Accepted Answer

A

Question 23

23 DNA polymerase catalyses condensation reactions between molecules during semi-conservative replication of DNA. Which two molecules are joined by DNA polymerase? A base and base B base and nucleotide C nucleotide and nucleotide D phosphate and deoxyribose

Accepted Answer

C

Question 24

24 What occurs during each of DNA replication and transcription and translation? 1 ATP provides energy. 2 Condensation reactions occur to form a polymer. 3 Hydrogen bonds form between purine and pyrimidine bases. A 1, 2 and 3 B 1 and 2 only C 2 only D 3 only

Accepted Answer

A

Question 25

25 Part of a sequence of DNA from a person with a genetic disease is: TAGTAACCACAAAGG The corresponding sequence of DNA from a person without this genetic disease is: TAGTAAAAACCACAAAGG The possible mRNA codons for some amino acids are shown in the table. amino acid mRNA codons 1 GGU GGC GGA GGG 2 AUU AUC AUA 3 UUU UUC 4 UCU UCC UCA UCG Which amino acid is missing from a person with this genetic disease? A 1 B 2 C 3 D 4

Accepted Answer

C

Question 26

26 The photomicrograph shows a section through a plant organ. Which statement could be used to describe this organ? A The central region of this organ has supporting tissue. B The endodermis tissue is a thick layer around the edge of the organ. C The epidermis tissue in this organ has unicellular extensions (trichomes). D The xylem tissue is found in greatest density in the centre of the organ.

Accepted Answer

C

Question 27

27 Which diagram correctly represents part of a sieve tube element? A B lignified cell wall dense cytoplasm empty lumen nucleus sieve plate sieve plate C D tonoplast thin layer of cytoplasm vacuole cellulose cell wall sieve plate sieve plate

Accepted Answer

D

Question 28

28 Which of the processes involved in water movement through xylem vessels depends on hydrogen bonding between water molecules? A adhesion B cohesion C evaporation D hydrostatic pressure

Accepted Answer

B

Question 29

29 Which statements about water movement in plants are correct? 1 Water can pass through cellulose. 2 Water cannot pass through lignin. 3 Water can pass through suberin. A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Accepted Answer

B

Question 30

30 Which blood vessel has the thickest walls? A D B C

Accepted Answer

A

Question 31

31 Which statement about the role in the mammalian circulatory system of the heart, blood vessels and blood is correct? A The contraction of heart muscle causes blood to enter arteries that pump the blood to organs, causing the formation of tissue fluid between cells before returning to the heart in veins. B The heart connects two sets of blood vessels so that oxygen from the lungs can be distributed by red blood cells and wastes can be collected from tissues by blood plasma for removal. C The heart muscle contracts and relaxes causing blood, carrying materials from one part of the body to another, to move through blood vessels that connect the different parts of the body. D The heart provides enough pressure to push blood through arteries to capillaries between cells causing filtration of blood and the formation of tissue fluid which diffuses back into veins.

Accepted Answer

C

Question 32

32 What explains how the maximum uptake of oxygen occurs 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 33

33 At high altitudes, the oxygen content of the air may be a third of that at sea level. As a person climbs a mountain, their body gradually adjusts to the high altitude. What is increased during this period of adjustment? A the concentration of haemoglobin in the red blood cells B the oxygen-carrying capacity of the haemoglobin C the number of red blood cells per mm3 of blood D the rate at which haemoglobin releases oxygen to the tissues

Accepted Answer

C

Question 34

34 What helps to maintain a concentration gradient between blood and the air in the alveolus? A the flow of blood through the lungs B the presence of haemoglobin in blood cells C the single-celled alveolar walls D the squamous epithelium of capillaries

Accepted Answer

A

Question 35

35 The diagram shows three features found in the tissues of the gas exchange system. Y goblet ciliated cells epithelium X cartilage Which structures of the gas exchange system could be represented at position X and at position Y in the diagram? 1 bronchiole 2 trachea 3 bronchus X Y A 1 2 and 3 B 1 and 3 2 C 2 1 and 3 D 2 and 3 1

Accepted Answer

D

Question 36

36 Blood tests on people who regularly smoke cigarettes show that approximately 5% of their haemoglobin carries carbon monoxide. People who smoke e-cigarettes inhale a vapour with no carbon monoxide. A person who smokes cigarettes regularly, switches to e-cigarettes and a blood test is carried out after a month. Which chemical in the blood would be found in a lower concentration in this blood test? A carbaminohaemoglobin B carbonic anhydrase C carboxyhaemoglobin D hydrogencarbonate ions

Accepted Answer

C

Question 37

37 Emphysema is a type of chronic obstructive pulmonary disease, COPD. People with emphysema have a very low level of a plasma protein which inhibits the enzyme elastase. Elastase breaks down the elastic fibres in the bronchioles and alveoli. Which are effects of the low levels of inhibitor in people with emphysema? 1 alveoli do not stretch and recoil properly during inhalation and exhalation 2 blood is poorly oxygenated resulting in a rapid breathing rate 3 bronchioles collapse during exhalation trapping air in the alveoli A 1, 2 and 3 B 1 and 3 only C 1 only D 2 and 3 only

Accepted Answer

A

Question 38

38 Some antibiotics work by binding to ribosomes. Which statement explains why these antibiotics kill bacteria cells but do not kill most human cells? A mRNA in bacteria is formed in the cytoplasm from naked DNA. B The antibiotics cannot pass through human cell membranes. C The codes used for amino acids in bacteria are different from those used by humans. D The ribosomes of bacteria have a different structure from those of humans.

Accepted Answer

D

Question 39

39 Where are antigens found?

0 0O WwW >

on the surface
of pathogen

«x «4

on the surface
of macrophage

x < x

in blood plasma

Kj « < x

key

¥ = antigens found

X = antigens not found

Accepted Answer

A

Question 40

40 The diagram allows the identification of different types of immunity. immunity short term long term 1 acquired by fetus from acquired by injection acquired as a result acquired by injection the maternal circulation of antibodies into of infection by a of an attenuated across the placenta the bloodstream pathogen pathogen 2 3 Which row correctly identifies the types of immunity labelled 1, 2 and 3? 1 2 3 A active artificial natural B active natural artificial C passive artificial natural D passive natural artificial

Accepted Answer

D

Question paper16 pages

Mark scheme3 pages

Questions as text

Q1 · Which steps are needed to find the actual width of a xylem vessel viewed in transverse…

Q2 · The diagram shows functions of four cell structures, W, X, Y and Z

Q3 · Which cell structures produce ATP?

Q4 · When mucus is secreted from a goblet cell these events take place

Q5 · Which row could be correct for a virus?

Q6 · Which size range would include most prokaryotic cells?

Q7 · Solutions of three biological molecules are tested for sugars

Q8 · A solution containing equal masses of amylose and amylopectin is completely hydrolysed

Q9 · Which molecules contain the following bonds?

Q10 · Which feature of phospholipids enables a bilayer to form?

Q11 · Which description is correct for collagen?

Q12 · Which statement about the properties of water is correct?

Q13 · Catechol is a chemical found in a number of fruits

Q14 · Four students investigated the effect of catalase on hydrogen peroxide

Q15 · What is the effect of an enzyme in an enzyme-catalysed reaction?

Q16 · The diagram shows part of the cell surface membrane

Q17 · Which processes use energy in the form of ATP?

Q18 · The diagram shows a partially plasmolysed plant cell

Q19 · Which features of an organism are affected by a drug that stops mitosis?

Q20 · Which row shows the appearance of a chromosome at the beginning of prophase of mitosis…

Q21 · The graph shows measurements taken during one mitotic cell cycle

Q22 · The diagram shows the outline structure of two nucleotide bases which occur in DNA

Q23 · DNA polymerase catalyses condensation reactions between molecules during…

Q24 · What occurs during each of DNA replication and transcription and translation?

Q25 · Part of a sequence of DNA from a person with a genetic disease is: TAGTAACCACAAAGG The…

Q26 · The photomicrograph shows a section through a plant organ

Q27 · Which diagram correctly represents part of a sieve tube element?

Q28 · Which of the processes involved in water movement through xylem vessels depends on…

Q29 · Which statements about water movement in plants are correct?

Q30 · Which blood vessel has the thickest walls?

Q31 · Which statement about the role in the mammalian circulatory system of the heart, blood…

Q32 · What explains how the maximum uptake of oxygen occurs as blood passes through the…

Q33 · At high altitudes, the oxygen content of the air may be a third of that at sea level

Q34 · What helps to maintain a concentration gradient between blood and the air in the alveolus?

Q35 · The diagram shows three features found in the tissues of the gas exchange system

Q36 · Blood tests on people who regularly smoke cigarettes show that approximately 5% of their…

Q37 · Emphysema is a type of chronic obstructive pulmonary disease, COPD

Q38 · Some antibiotics work by binding to ribosomes

Q39 · Where are antigens found?

Q40 · The diagram allows the identification of different types of immunity

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