Cambridge A Level Biology 9700 — 2019 May/June Paper 1 · Variant 1

Question 1

1 A student was told that the actual length of a cell structure is 5 µm. The student was asked to state an equation that can be used to calculate the magnification of an electron micrograph of this cell structure. The student used some of the letters q to u in the equation. q = the length of the cell structure image on the micrograph in centimetres r = the length of the cell structure image on the micrograph in millimetres s = 1000 t = 5 1 u = 5 Which is the correct equation to calculate the magnification? q r A s  × u B q × s × t C s  × u D r × s × t

Accepted Answer

D

Question 2

2 Which features of cilia and root hairs are correct? cannot be more than one increase cell resolved with contain present on a surface area the light vacuoles cell microscope A cilia cilia root hairs root hairs B cilia root hairs cilia cilia C root hairs cilia root hairs cilia D root hairs root hairs cilia root hairs

Accepted Answer

C

Question 3

3 Which are functions of microtubules? 1 allowing movement of cilia in a bronchus 2 attachment of centromeres during metaphase 3 moving secretory vesicles around a cell A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Accepted Answer

A

Question 4

4 Some cell structures are listed. 1 mitochondria 2 nucleus 3 chloroplasts 4 ribosomes What is the correct order of these cell structures when listed from largest to smallest? A 1, 2, 3, 4 B 2, 3, 1, 4 C 2, 4, 1, 3 D 3, 4, 2, 1

Accepted Answer

B

Question 5

5 Which cell structures have ribosomal RNA (rRNA)? 1 chloroplast 2 mitochondrion 3 nucleus 4 rough endoplasmic reticulum A 1, 2, 3 and 4 B 1, 2 and 3 only C 1, 2 and 4 only D 2, 3 and 4 only

Accepted Answer

A

Question 6

6 A cell structure in the macrophage destroys bacteria. Some bacteria stop this cell structure from functioning. Which cell structure in the macrophage is stopped from functioning by the bacteria? A Golgi body B lysosome C ribosome D vesicle

Accepted Answer

B

Question 7

7 A solution of amylase was added to a suspension of starch. After 30 seconds, three samples of the mixture were tested with iodine solution, Benedict’s solution or with biuret reagent. Which are the expected results? colour with test reagent iodine solution Benedict’s solution biuret reagent A black green purple B black red blue C brown blue purple D brown yellow blue

Accepted Answer

A

Question 8

8 A student carried out a Benedict’s test on several different known concentrations of α-glucose. Which graph represents the results correctly? A B time to first concentration colour change of α-glucose 0 0 0 concentration 0 time to first of α-glucose colour change C D concentration time to first of α-glucose colour change 0 0 0 time to first 0 concentration colour change of α-glucose

Accepted Answer

A

Question 9

9 The diagram shows three hexose sugars. CH2OH CH2OH CH2OH O C O C O H H H OH OH H H C C C C C C OH H OH H H OH HO OH HO H H CH2OH C C C C C C H OH H OH OH H 1 2 3 Which row correctly shows examples of carbohydrates in which these three hexose sugars occur? sucrose cellulose starch A 1 2 3 B 1 3 2 C 2 3 1 D 3 2 1

Accepted Answer

D

Question 10

10 What can occur during condensation of carbohydrates? A a disaccharide is produced from monosaccharides B glycosidic bonds are broken C molecules of water are used up D monosaccharides are produced

Accepted Answer

A

Question 11

11 What is true about triglycerides?

hydrophobic insoluble in alcohol
A J Jv key
B v x ¥ = correct
Cc x v X = not correct
D x x

Accepted Answer

B

Question 12

12 What is the minimum number of carbon atoms in an amino acid? A 1 B 2 C 3 D 4

Accepted Answer

B

Question 13

13 In an investigation, the same concentration of the enzyme phosphorylase was added to different concentrations of glucose phosphate and incubated at 30 °C. At 1 minute intervals, one drop of the reaction mixture was removed and added to a drop of iodine solution on a white tile. The diagram shows the results of this investigation. concentration of glucose phosphate / mg dm–3 0 5 10 15 20 25 30 35 colour of 0 iodine solution 1 2 brown 3 black time / minutes 4 5 6 7 8 9 What explains the trend in the results of this investigation? A Phosphorylase catalyses a reaction converting glucose phosphate to starch. B The maximum rate of reaction is reached at 20 mg dm–3 of glucose phosphate. C Substrate concentration is limiting at concentrations of glucose phosphate 25 mg dm–3 or less. D Enzyme concentration is limiting at concentrations of glucose phosphate 25 mg dm–3 or less.

Accepted Answer

C

Question 14

14 What is the definition of the Michaelis-Menten constant, Km, for an enzyme? A Vmax B half Vmax C the substrate concentration that gives Vmax D the substrate concentration that gives half Vmax

Accepted Answer

D

Question 15

15 The graph shows how the rate of entry of glucose into a cell changes as the concentration of glucose outside the cell changes. X rate of entry of glucose into the cell concentration of glucose outside the cell What is the cause of the plateau at X? A All the carrier proteins are saturated with glucose. B The carrier proteins are denatured and no longer able to function. C The cell has used up its supply of ATP. D The concentrations of glucose inside and outside the cell are equal.

Accepted Answer

A

Question 16

16 The diagram shows the movement of substance Z across a cell surface membrane. Z outside cell membrane Z Z inside cell time Which process is involved in this movement? A endocytosis B exocytosis C phagocytosis D pinocytosis

Accepted Answer

B

Question 17

17 Visking tubing is often used as a model during experiments to investigate osmosis in plants.

What could Visking tubing be used to represent?

cell surface
cell wall tonoplast
membrane
v v
v v
v x
x v

key
/ = represents

X = does not represent

Accepted Answer

B

Question 18

18 A scientist stains the chromosomes of a diploid plant cell with a fluorescent dye to observe the telomeres. This cell has 38 chromosomes. How many telomeres will the scientist observe in one of the nuclei during telophase of mitosis? A 38 B 76 C 114 D 152

Accepted Answer

B

Question 19

19 The photomicrograph shows a cell during mitosis. What is happening in this cell? 1 Centrioles are replicating. 2 Spindle microtubules are shortening. 3 Chromatin is condensing. A 1, 2 and 3 B 1 and 2 only C 2 only D 3 only

Accepted Answer

C

Question 20

20 Which events listed are part of mitosis? 1 interphase 2 prophase 3 cytokinesis A 1, 2 and 3 B 1 and 2 only C 1 only D 2 only

Accepted Answer

D

Question 21

21 The graph shows the length of the spindle fibres during mitosis. Which region of the graph shows when all the centromeres have detached from the spindle fibres? B C length of spindle fibres A D time

Accepted Answer

D

Question 22

22 A short piece of DNA, 19 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 4 strand 2 7 5 How many nucleotide bases containing C were present in strand 1? A 2 B 3 C 5 D 7

Accepted Answer

B

Question 23

23 Which nucleic acid bases are purines? A adenine and cytosine B cytosine and thymine C guanine and adenine D uracil and cytosine

Accepted Answer

C

Question 24

24 In a genetic engineering experiment a piece of double-stranded DNA containing 6000 nucleotides coding for a specific polypeptide is transcribed and translated. What is the total number of amino acids in this polypeptide? A 500 B 1000 C 2000 D 3000

Accepted Answer

B

Question 25

25 Which statements about tRNA are correct? 1 Hydrogen bonds between bases temporarily hold tRNA against mRNA. 2 The base sequences in the tRNA molecules are the same as the base sequences in the mRNA that is being translated. 3 tRNA translates the base sequence in mRNA into the amino acid sequence in a protein. A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Accepted Answer

C

Question 26

26 The photomicrograph shows a transverse section of part of a dicotyledonous leaf. 1 4 2 3 What are the correct labels for 1, 2, 3 and 4? 1 2 3 4 A phloem xylem palisade mesophyll spongy mesophyll B phloem xylem spongy mesophyll palisade mesophyll C xylem phloem palisade mesophyll spongy mesophyll D xylem phloem spongy mesophyll palisade mesophyll

Accepted Answer

D

Question 27

27 Some of the features present in transport tissues in plants are listed. 1 lignified walls 2 cytoplasm 3 mitochondria 4 pits 5 plasmodesmata Which of these features are present in phloem sieve tube elements? A 1, 2 and 5 B 1, 3 and 4 C 2, 3 and 5 D 2, 4 and 5

Accepted Answer

C

Question 28

28 The diagram shows the relationship between phloem sieve tube elements, xylem vessel elements and companion cells. 1 3 5 2 4 Which row is correct? 1 2 3 4 5 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 C phloem sieve mitochondria companion nucleus xylem vessel tube elements cells elements D xylem vessel no phloem sieve vacuole companion elements cytoplasm tube elements cells

Accepted Answer

A

Question 29

29 Which statement correctly describes a transport pathway in plants? A In the apoplast pathway, water may move through plasmodesmata. B In the symplast pathway, water may move through intercellular spaces. C The apoplast pathway may be blocked by the Casparian strip. D The symplast pathway may be blocked by the tonoplast.

Accepted Answer

C

Question 30

30 The photograph shows an external view of the front of a mammalian heart. S P R Q Which row identifies the position of the structures labelled P, Q, R and S? P Q R S A left atrium cardiac muscle Purkyne tissue pulmonary vein B left atrium left ventricle coronary artery vena cava C right atrium cardiac muscle Purkyne tissue aorta D right atrium right ventricle coronary artery pulmonary artery

Accepted Answer

B

Question 31

31 What happens during ventricular systole? 1 The atrioventricular node transmits an electrical signal to the apex of the heart. 2 The pressure in the ventricles drops below the pressure in the atria. 3 The atrioventricular valves close and the semilunar valves open. A 1 and 2 only B 1 and 3 only C 2 only D 3 only

Accepted Answer

D

Question 32

32 Athletes often move from low altitude to high altitude to train for a race. Which statements about the effect of training at high altitude are correct? 1 Higher concentrations of carbon dioxide stimulate greater oxygen dissociation. 2 Lower concentrations of oxygen stimulate the uptake of more oxygen by red blood cells. 3 Lower partial pressures of oxygen stimulate higher production of red blood cells. A 1 and 2 only B 2 and 3 only C 1 only D 3 only

Accepted Answer

D

Question 33

33 The graph shows the oxygen haemoglobin dissociation curves at pH 7.6 and at pH 7.2. Which point on the graph shows the percentage saturation of haemoglobin in the blood leaving an active muscle? pH 7.6 C pH 7.2 A D percentage B saturation of haemoglobin partial pressure of oxygen

Accepted Answer

B

Question 34

34 Which row correctly describes the short-term effects of carbon monoxide and nicotine on the body of a smoker? demand for oxygen concentration of oxygen in blood A decreased by carbon monoxide increased by nicotine B decreased by nicotine increased by carbon monoxide C increased by carbon monoxide decreased by nicotine D increased by nicotine decreased by carbon monoxide

Accepted Answer

D

Question 35

35 Which statements about bronchioles are correct? 1 They have ciliated cells. 2 They have goblet cells. 3 They have muscle tissue. A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Accepted Answer

C

Question 36

36 Which features are important for the diffusion of oxygen out of an alveolus? 1 blood pressure forces red blood cells through capillaries 2 4 epithelium is surfactant present to features permeable to reduce surface tension respiratory gases 3 moist squamous epithelium present A 1, 2 and 3 B 1, 3 and 4 C 1 and 3 only D 2 and 4 only

Accepted Answer

A

Question 37

37 The diagram shows some of the pathogens that cause disease in humans and some of the ways they are transmitted. 1 2 W bacterium protoctist contaminated water pathogen method of transmission 3 Y X Morbillivirus contaminated coughs and food sneezes What is the correct pathogen and method of transmission for measles? A 1 and X B 2 and W C 3 and W D 3 and X

Accepted Answer

D

Question 38

38 Which row is correct for each disease? cholera HIV / AIDS malaria measles A caused by a can be transmitted eradication caused by bacterium in breast milk programme a virus and across placenta unsuccessful B eating raw may be carried carried by male can cause shellfish can be by a vector Anopheles blindness a source of infection mosquitoes C air borne caused by causative agent is a symptoms usually infection a retrovirus eukaryote include a rash D can be caught by causes reduction mainly kills children no effective swimming in in number of under five years vaccination available contaminated water T-lymphocytes

Accepted Answer

A

Question 39

39 Which statements describe myasthenia gravis? 1 Antibodies attack proteins within the body. 2 T-lymphocytes are involved in an inflammatory response. 3 The immune system blocks receptors at the neuromuscular junction. 4 The immune system attacks the central nervous system. A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

Accepted Answer

A

Question 40

40 Which row shows the cells that are able to divide continuously and are involved in monoclonal
antibody production?

cancer cells

mouse
B-lymphocyte
plasma cells

hybridoma
cells

v

v
x
v

key
/ = correct

X = not correct

Accepted Answer

C

Question paper16 pages

Mark scheme3 pages

Questions as text

Q1 · A student was told that the actual length of a cell structure is 5 µm

Q2 · Which features of cilia and root hairs are correct?

Q3 · Which are functions of microtubules?

Q4 · Some cell structures are listed

Q5 · Which cell structures have ribosomal RNA (rRNA)?

Q6 · A cell structure in the macrophage destroys bacteria

Q7 · A solution of amylase was added to a suspension of starch

Q8 · A student carried out a Benedict’s test on several different known concentrations of…

Q9 · The diagram shows three hexose sugars

Q10 · What can occur during condensation of carbohydrates?

Q11 · What is true about triglycerides?

Q12 · What is the minimum number of carbon atoms in an amino acid?

Q13 · In an investigation, the same concentration of the enzyme phosphorylase was added to…

Q14 · What is the definition of the Michaelis-Menten constant, Km, for an enzyme?

Q15 · The graph shows how the rate of entry of glucose into a cell changes as the concentration…

Q16 · The diagram shows the movement of substance Z across a cell surface membrane

Q17 · Visking tubing is often used as a model during experiments to investigate osmosis in…

Q18 · A scientist stains the chromosomes of a diploid plant cell with a fluorescent dye to…

Q19 · The photomicrograph shows a cell during mitosis

Q20 · Which events listed are part of mitosis?

Q21 · The graph shows the length of the spindle fibres during mitosis

Q22 · A short piece of DNA, 19 base pairs long, was analysed to find the number of nucleotide…

Q23 · Which nucleic acid bases are purines?

Q24 · In a genetic engineering experiment a piece of double-stranded DNA containing 6000…

Q25 · Which statements about tRNA are correct?

Q26 · The photomicrograph shows a transverse section of part of a dicotyledonous leaf

Q27 · Some of the features present in transport tissues in plants are listed

Q28 · The diagram shows the relationship between phloem sieve tube elements, xylem vessel…

Q29 · Which statement correctly describes a transport pathway in plants?

Q30 · The photograph shows an external view of the front of a mammalian heart

Q31 · What happens during ventricular systole?

Q32 · Athletes often move from low altitude to high altitude to train for a race

Q33 · The graph shows the oxygen haemoglobin dissociation curves at pH 7.6 and at pH 7.2

Q34 · Which row correctly describes the short-term effects of carbon monoxide and nicotine on…

Q35 · Which statements about bronchioles are correct?

Q36 · Which features are important for the diffusion of oxygen out of an alveolus?

Q37 · The diagram shows some of the pathogens that cause disease in humans and some of the ways…

Q38 · Which row is correct for each disease?

Q39 · Which statements describe myasthenia gravis?

Q40 · Which row shows the cells that are able to divide continuously and are involved in…

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