Cambridge A Level Biology 9700 — 2014 Oct/Nov Paper 1 · Variant 2

Question 1

1 Which combination of lenses for a light microscope will give the greatest magnification? eyepiece lens objective lens A ×5 ×100 B ×10 ×40 C ×15 ×40 D ×15 ×100

Accepted Answer

D

Question 2

2 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 2, 3 and 4 only C 1 and 2 only D 3 and 4 only

Accepted Answer

D

Question 3

3 The statements are all descriptions of cell structures. 1 surrounded by a single membrane and enclosing a large fluid-filled space 2 surrounded by a single membrane and enclosing inactivated enzymes 3 formed by two membranes enclosing a matrix, the inner membrane is folded 4 formed by a membrane that has flattened sacs and tubular structures inter-connected throughout the cell 5 formed of nucleic acid and protein attached to membranes or free in the cytoplasm Which row shows the typical cell in which these cell structures are found? plant cell animal cell A 1, 2, 3 and 4 1, 2, 3 and 5 B 1, 3, 4 and 5 2, 3, 4 and 5 C 2, 4 and 5 1, 4 and 5 D 3, 4 and 5 only 2, 3 and 5 only

Accepted Answer

B

Question 4

4 Which structures are found in both typical eukaryotic cells and typical prokaryotic cells? 1 70S ribsomes 2 80S ribosomes 3 circular DNA A 1, 2 and 3 B 1 and 3 only C 1 only D 2 only

Accepted Answer

B

Question 5

5 Which sequence shows some of the stages in the production and secretion of an enzyme? A Golgi apparatus  →  ribosome  →  rough endoplasmic reticulum  →  mRNA B mRNA  →  smooth endoplasmic reticulum  →  Golgi apparatus  →  vesicle C ribosome  →  rough endoplasmic reticulum  →  vesicle  →  Golgi apparatus D smooth endoplasmic reticulum  →  mRNA  →  vesicle  →  ribosome

Accepted Answer

C

Question 6

6 Which plan diagram of a transverse section of a dicotyledonous leaf correctly shows the position of xylem and phloem in a palisade mesophyll layer that is twice as thick as the spongy mesophyll layer? A B xylem phloem phloem xylem C D xylem phloem phloem xylem

Accepted Answer

C

Question 7

7 Proteases are a group of enzymes that digest proteins. Which statement about proteases is correct? A A bacterial protease that is secreted from a disease-causing bacterium could act as an antigen and cause the production of an antibody. B Bacterial proteases are important in the nitrogen cycle as they are able to catalyse the breakdown of the organic nitrogen molecules nucleotides and urea. C Non-competitive inhibition of a protease that has an optimum pH of pH2 can be overcome by increasing the substrate concentration and increasing the pH. D Water molecules are required when peptide bonds that link the monomers together are broken by the action of proteases in condensation reactions.

Accepted Answer

A

Question 8

8 Two disaccharides are maltose and sucrose. Maltose is formed from two molecules of glucose, whilst sucrose is formed from fructose and glucose. Which row shows the molecular formulae of the two disaccharides? maltose sucrose A C12H22O11 C12H22O11 B C12H22O11 C12H24O12 C C12H24O12 C12H22O11 D C12H24O12 C12H24O12

Accepted Answer

A

Question 9

9 The diagram shows a carbohydrate molecule. CH2OH C O OH HO O HO CH2OH CH2 CH2OH C O C O C O OH OH OH O O HO OH HO HO HO Of which polymers could this be a part? A amylopectin and cellulose B amylose and starch C glycogen and amylose D starch and glycogen

Accepted Answer

D

Question 10

10 Which of the bonds stabilising the tertiary structure of a protein would be least likely to break when the temperature is increased above the optimum for the protein? A disulfide B hydrogen C hydrophobic D ionic

Accepted Answer

A

Question 11

11 The diagram shows the structure of four amino acids in solution. COO– COO– H C H3N+ CH2 CH2 CH2 CH2 C NH3 + NH3 + H H glycine lysine COO– O COO– CH3 C C CH2 C NH3 + O– NH3 + H H alanine aspartate Which amino acids have no overall charge? A alanine and aspartate B alanine and glycine C aspartate and lysine D glycine and lysine

Accepted Answer

B

Question 12

12 The statements are about the properties of water. 1 It requires a lot of heat to evaporate. 2 It retains a lot of heat. 3 It is able to form hydrogen bonds with other water molecules. 4 It is able to form hydrogen bonds with other polar and non-polar molecules. Which properties are important in transpiring plants to prevent enzymes in leaves from being denatured? A 1 only B 1 and 2 only C 2 and 3 only D 1, 2, 3 and 4

Accepted Answer

A

Question 13

13 Which words from the table correctly complete the paragraph about enzymes? When the pH of an environment is decreased below an enzyme’s optimum pH, ……1…… bonds between adjacent ……2…… groups, holding the ……3…… structure, are disrupted. 1 2 3 A hydrogen and ionic R tertiary B hydrogen hydroxyl secondary C ionic and peptide R primary and tertiary D peptide amine primary

Accepted Answer

A

Question 14

14 Lipase is a digestive enzyme produced by the pancreas that catalyses the hydrolysis of dietary lipids. The table shows how the pH of a liquid food containing a high proportion of lipids decreases over time. 8 pH of a 7 liquid food 6 0 5 10 15 20 25 30 35 40 45 50 55 60 time / min Which statements are possible explanations of the results of the experiment between 50 and 60 minutes? 1 Enzyme concentration becomes the limiting factor. 2 Substrate concentration becomes the limiting factor. 3 All the enzyme active sites are saturated. 4 Denaturation of the enzyme by the products. 5 Products are acting as competitive inhibitors. A 1, 2 and 3 B 1, 4 and 5 C 2, 3 and 4 D 2, 4 and 5

Accepted Answer

D

Question 15

15 The AIDS virus produces a long polypeptide that is hydrolysed by a protease enzyme, producing several smaller peptides. This viral protease is the target of anti-AIDS drugs. Which feature is essential for the success of these drugs? A a complex structure that inhibits many types of viral enzyme B a molecule containing a heavy metal atom that is a non-competitive inhibitor of enzymes C a protein that can act as a competitive inhibitor of protease enzymes D a specific structure that inhibits only viral protease

Accepted Answer

D

Question 16

16 What is the width of the cell surface membrane? A 0.5 – 1.0 nm B 5 – 10 nm C 50 – 100 nm D 0.5 – 1 µm

Accepted Answer

B

Question 17

17 Some functions of molecules found in cell surface membranes are listed. 1 cell recognition 2 ion transport 3 maintaining fluidity 4 mechanical stability Which are functions of cholesterol? A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

Accepted Answer

D

Question 18

18 The enzyme lactase is found in the membranes of epithelial cells lining the small intestine. The enzyme is formed by a single polypeptide that folds to give three regions. • an active site with the free amino group outside the cell • a short section inside the membrane • a short section inside the cell What type of amino acid would be found in each of the three regions? inside the inside the outside cell membrane cell A hydrophilic hydrophobic hydrophilic B hydrophilic hydrophobic hydrophobic C hydrophobic hydrophilic hydrophobic D hydrophobic hydrophobic hydrophilic

Accepted Answer

A

Question 19

19 A student examined the cells in the growing region (meristem) of an onion root and obtained the data below. stage number of cells interphase 886 prophase 73 metaphase 16 anaphase 14 telophase 11 What percentage of cells contain chromosomes that appear as two chromatids? A 97.5 % B 95.9 % C 8.9 % D 7.3 %

Accepted Answer

C

Question 20

20 Which definitions of diploid and haploid are true for typical eukaryotic cells? 1 diploid – any cell with an even number of homologous chromosomes 2 diploid – any cell with two copies of each homologous chromosome 3 haploid – any cell with half the diploid number of homologous chromosomes 4 haploid – any cell with one copy of each homologous chromosome A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

Accepted Answer

D

Question 21

21 Which type of sugar and types of bonds are found in a DNA molecule? type of sugar types of bonds A non-reducing hydrogen and ionic B non-reducing hydrogen and peptide C reducing covalent and hydrogen D reducing hydrogen and peptide

Accepted Answer

C

Question 22

22 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 23

23 A short piece of DNA 15 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 guanine were present in strand 1? A 2 B 3 C 4 D 6

Accepted Answer

A

Question 24

24 The diagram shows a transverse section of a stem. Which area is the phloem? A D C B

Accepted Answer

B

Question 25

25 A leafy shoot was attached to a potometer and exposed to a variety of conditions. The time taken for the meniscus to move 50 mm along the capillary tubing was recorded for each set of conditions. time taken to temperature air humidity move 50 mm / °C movement / s 20 dry still 125 20 dry moving 71 30 dry still 40 20 humid still 166 20 humid moving 83 30 humid still 55 Which shows the slowest and fastest rates of water uptake? slowest fastest / mm s–1 / mm s–1 A 0.3 1.3 B 0.3 3.3 C 3.3 0.3 D 1.3 0.8

Accepted Answer

A

Question 26

26 The diagram shows four plant cells. 1 4 2 3 In which direction could there be net movement of water by osmosis? A 1 to 2 and 1 to 4 B 1 to 3 and 1 to 2 C 2 to 1 and 1 to 4 D 4 to 1 and 2 to 3

Accepted Answer

A

Question 27

27 How will the root pressure in a plant be affected by waterlogged soil? A It will not be affected. B It will decrease due to a lack of oxygen in the soil. C It will increase due to a lower water potential in the soil. D It will increase due to a higher rate of transpiration.

Accepted Answer

B

Question 28

28 The diagram shows the relationship between phloem sieve tube elements, xylem vessel elements and companion cells. 1 2 3 4 5 Which is correct? 1 2 3 4 5 A companion endoplasmic phloem sieve nucleus absent xylem vessel cells reticulum tube elements 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 cytoplasm phloem sieve vacuole companion elements absent tube elements cells

Accepted Answer

A

Question 29

29 Small arteries (arterioles) are found near tissues. One function of an arteriole is to increase or decrease the flow of blood to the tissues. Which tissues would be present in an arteriole wall to allow this function? 1 collagen 2 elastic 3 muscle A 1, 2 and 3 B 1 and 3 only C 2 only D 3 only

Accepted Answer

D

Question 30

30 The graph shows a dissociation curve for haemoglobin. y-axis x-axis Which are suitable labels for the x-axis and the y-axis? x-axis y-axis A partial pressure of carbon dioxide percentage of haemoglobin B partial pressure of oxygen percentage saturation of haemoglobin with oxygen C percentage of haemoglobin partial pressure of oxygen D percentage saturation of haemoglobin partial pressure of carbon dioxide with oxygen

Accepted Answer

B

Question 31

31 One type of congenital heart defect is called atrial septal defect (ASD) where the left and right atria are not completely separated. ASD usually results in blood moving from the left atrium into the right atrium. This will cause increased blood pressure in the right atrium and decreased blood pressure in the left atrium. Which row describes the other effects of ASD on blood pressure and oxygenation? blood pressure in blood pressure % oxygenation of blood pulmonary artery in aorta in pulmonary artery A decreased increased decreased B decreased increased increased C increased decreased decreased D increased decreased increased

Accepted Answer

D

Question 32

32 Which are effects on the body of carbon monoxide in tobacco smoke? 1 It reduces the amount of haemoglobin available to transport oxygen. 2 It reduces the rate of diffusion of oxygen from the alveoli into the blood. 3 It inhibits the release of oxygen from haemoglobin. A 1, 2 and 3 B 2 and 3 only C 1 only D 3 only

Accepted Answer

C

Question 33

33 The graph shows the volume of air breathed out quickly and with force, following a deep breath in, for three different people, X, Y and Z. 5 X 4 Y 3 volume / dm3 2 Z 1 0 0 1 2 3 4 5 time / s What is a possible explanation for the differences in the volume of air breathed out by these people shown? chronic bronchitis emphysema normal lung function A X Z Y B Y X Z C Y Z X D Z Y X

Accepted Answer

C

Question 34

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

Accepted Answer

A

Question 35

35 Which statements about people infected with HIV / AIDS are correct? 1 They can be treated and completely cured. 2 They may live for many years after infection. 3 They will have symptoms. A 1, 2 and 3 B 1 and 3 only C 2 only D 3 only

Accepted Answer

C

Question 36

36 The statements refer to polio and tuberculosis (TB). 1 Macrophages present antigens in vaccines to stimulate an immune response. 2 The TB antigens necessary to produce an immune response are proteins which would be digested in the stomach and small intestine. 3 There are no B-lymphocytes and T-lymphocytes in the stomach. Which explains why polio vaccine can be taken by mouth but TB vaccine has to be injected? A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 only

Accepted Answer

D

Question 37

37 Which explains why sickle cell anaemia has not been eradicated? A Identification of carriers is too difficult as they show no symptoms. B Sickle cell anaemia gives the individual some resistance against malaria. C Sickle cell anaemia is an inherited disease, so vaccination is not possible. D The gene responsible for sickle cell anaemia has a high rate of mutation.

Accepted Answer

C

Question 38

38 Which method of gaining immunity can be described as natural active immunity? A feeding on colostrum B inhaling the chicken pox virus C injection with antibodies D through the placenta

Accepted Answer

B

Question 39

39 Which stage of energy transfer has the lowest efficiency? A sunlight → producer B producer → primary consumer C primary consumer → secondary consumer D secondary consumer → tertiary consumer

Accepted Answer

A

Question 40

40 The diagram shows a simplified nitrogen cycle. During which stage does decomposition take place? nitrogen in atmosphere A plant animal proteins proteins B ammonium compounds nitrites nitrates C D

Accepted Answer

B

Question paper16 pages

Mark scheme2 pages

Questions as text

Q1 · Which combination of lenses for a light microscope will give the greatest magnification?

Q2 · Which steps are needed to find the actual width of a xylem vessel viewed in transverse…

Q3 · The statements are all descriptions of cell structures

Q4 · Which structures are found in both typical eukaryotic cells and typical prokaryotic cells?

Q5 · Which sequence shows some of the stages in the production and secretion of an enzyme?

Q6 · Which plan diagram of a transverse section of a dicotyledonous leaf correctly shows the…

Q7 · Proteases are a group of enzymes that digest proteins

Q8 · Two disaccharides are maltose and sucrose

Q9 · The diagram shows a carbohydrate molecule

Q10 · Which of the bonds stabilising the tertiary structure of a protein would be least likely…

Q11 · The diagram shows the structure of four amino acids in solution

Q12 · The statements are about the properties of water

Q13 · Which words from the table correctly complete the paragraph about enzymes?

Q14 · Lipase is a digestive enzyme produced by the pancreas that catalyses the hydrolysis of…

Q15 · The AIDS virus produces a long polypeptide that is hydrolysed by a protease enzyme…

Q16 · What is the width of the cell surface membrane?

Q17 · Some functions of molecules found in cell surface membranes are listed

Q18 · The enzyme lactase is found in the membranes of epithelial cells lining the small…

Q19 · A student examined the cells in the growing region (meristem) of an onion root and…

Q20 · Which definitions of diploid and haploid are true for typical eukaryotic cells?

Q21 · Which type of sugar and types of bonds are found in a DNA molecule?

Q22 · Which nucleic acid bases are purines?

Q23 · A short piece of DNA 15 base pairs long was analysed to find the number of nucleotide…

Q24 · The diagram shows a transverse section of a stem

Q25 · A leafy shoot was attached to a potometer and exposed to a variety of conditions

Q26 · The diagram shows four plant cells

Q27 · How will the root pressure in a plant be affected by waterlogged soil?

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

Q29 · Small arteries (arterioles) are found near tissues

Q30 · The graph shows a dissociation curve for haemoglobin

Q31 · One type of congenital heart defect is called atrial septal defect (ASD) where the left…

Q32 · Which are effects on the body of carbon monoxide in tobacco smoke?

Q33 · The graph shows the volume of air breathed out quickly and with force, following a deep…

Q34 · Which flow diagram correctly describes the effect of tar entering the lungs?

Q35 · Which statements about people infected with HIV / AIDS are correct?

Q36 · The statements refer to polio and tuberculosis (TB)

Q37 · Which explains why sickle cell anaemia has not been eradicated?

Q38 · Which method of gaining immunity can be described as natural active immunity?

Q39 · Which stage of energy transfer has the lowest efficiency?

Q40 · The diagram shows a simplified nitrogen cycle

What was in this paper

What you needed in this session

Other variants, same session

This paper, other years