Time allowed: 2 hours Answer ALL questions in Section A, ALL PARTS of the question in Section B and ONE question from Section C.

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1 UNIVERSITY OF EAST ANGLIA School of Biological Sciences Main Series UG Examination FURTHER BIOLOGY BIO-0001B Time allowed: 2 hours Answer ALL questions in Section A, ALL PARTS of the question in Section B and ONE question from Section C. Write answers to EACH SECTION in the Answer Grid or SEPARATE booklet. The maximum number of marks available for your answers in SECTION A is 40 marks The maximum number of marks available for your answer in SECTION B is 30 marks The maximum number of marks available for your answer in SECTION C is 30 marks The TOTAL number of marks available for the paper is 100 Numbers in square brackets [ ] indicate the relevant mark applied to each part of the question. Graph paper is provided. Notes are not permitted in this examination. Do not turn over until you are told to do so by the Invigilator. BIO-0001B Module Contact: Dr Kelly Edmunds, BIO Copyright of the University of East Anglia Version 2

2 2 SECTION A: MULTIPLE CHOICE AND SHORT ANSWER QUESTIONS Answer ALL questions [40 marks] Answer multiple choice questions in the answer grid provided and attach this to your booklet for Section A. Unless stated otherwise, all multiple choice questions have ONE answer. 1. If a parent has the genotype Bb and they are crossed with a heterozygous individual of the same genotype, what proportion of the offspring would be homozygous dominant? [1 mark] a) 0 % b) 25 % c) 50 % d) 75 % e) 100 % 2. How many nucleotides are in a piece of DNA consisting of 3 codons? [1 mark] a) 3 b) 6 c) 8 d) 9 e) What human trait is an example of multiple alleles and co-dominance? [1 mark] a) Blood group b) Height c) Eye colour d) Colour blindness e) Huntington s disease 4. A light microscope can be used to observe structures with a minimum dimension of: [1 mark] a) 10 µm b) 5 µm c) 1 µm d) 0.5 µm e) 0.1 µm Section A continues on next page/...

3 3 Section A continued Convert 2.5 mm into µm. [1 mark] a) µm b) 2500 µm c) 250 µm d) 25 µm e) 2.5 µm 6. Starch is a: [1 mark] a) polysaccharide b) monosaccharide c) glycoprotein d) polypeptide e) oligosaccharide 7. The following image is of what functional group? [1 mark] a) Thiol b) Amine c) Ethyl d) Methyl e) Carboxyl 8. What two nitrogenous bases are purines? a) Cytosine b) Thymine c) Uracil d) Adenine e) Guanine Section A continues on next page/... TURN OVER

4 4 Section A continued In glycolysis, one molecule of glucose has a net yield of (select two answers): a) one molecule of Pyruvate b) two molecules of Pyruvate c) one Molecule of ATP d) two molecules of ATP e) one molecule of NADH 10. In the mammalian respiratory system, gas exchange occurs in the: [1 mark] a) pharynx b) trachea c) bronchioles d) bronchi e) alveoli 11. Chemoreceptors in the brain that regulate breathing measure changes in: [1 mark] a) CO2 b) O2 c) ph d) CO e) H2O 12. Arteries carry: [1 mark] a) blood away from the lungs b) blood towards the heart c) blood away from the heart d) blood away from capillaries e) blood towards veins Section A continues on next page/...

5 5 Section A continued On an ElectroCardiogram (ECG) reading what does the R wave represent? [1 mark] a) Atrial contraction b) Sinoatrial node c) Sinoventricular node d) Ventricular contraction e) Ventricular relaxation 14. What is the oxygen binding co-factor in haemoglobin? [1 mark] a) Cu b) Zn c) O2 d) CO2 e) Fe 15. What two parts make up the central nervous system? a) Spinal cord b) Local ganglia c) Cranial nerves d) Brain e) Spinal nerves 16. What is the resting potential of a neuron? [1 mark] a) - 70mV b) - 40 mv c) + 40 mv d) + 70 mv e) 0 mv Section A continues on next page/... TURN OVER

6 6 Section A continued Which one of the following genetic diseases arises from a single point mutation? [1 mark] a) Down s syndrome b) Huntington s disease c) Turner s syndrome d) Sickle cell anaemia e) Kleinfelter syndrome 18. What is the correct chemical equation for respiration? [1 mark] a) C6H12O6 + 6 O2 6 CO2 + 6 H2O + Energy b) C6H12O6 + 3 O2 3 CO2 + 6 H2O + Energy c) 6 CO2 + 6 H2O + Energy C6H12O6 + 3 O2 d) CO2 + H2O + Energy C6H12O6 + O2 e) C6H12O6 + O2 CO2 + H2O + Energy For all remaining questions in Section A, please use an answer booklet. Remember to attach your multiple choice answer grid to the booklet. 19. Name two main differences between RNA and DNA. 20. Identify two main differences between starch and glycogen. 21. Give an example of a charged ion and how it crosses the plasma membrane. 22. Give an example of an un-charged molecule and how it crosses the plasma membrane. 23. What are the names of the thick and thin filaments in a skeletal muscle cell? 24. Name a human disease in which the disease causing allele exhibits autosomal dominant inheritance. [1 mark] Section A continues on next page/...

7 7 Section A continued When an action potential is generated, which ions move across the membrane and in which directions? 26. Give two causes of microevolution. 27. In Drosophila the red eye trait is dominant (R) to the white eye trait (r). In a population of 100 flies 32 are RR, 50 Rr and 18 rr. Calculate the allele frequency of R and r in the population. 28. Give two effects that a genetic bottle neck can have on a population. END OF SECTION A START YOUR ANSWER TO THE NEXT SECTION IN A NEW BOOKLET Section B begins on next page/... TURN OVER

8 8 SECTION B: DATA HANDLING QUESTION ANSWER THIS SECTION IN A NEW BOOKLET Answer ALL PARTS of this question [30 marks] 29. The enzyme lactase breaks lactose (a disaccharide) into its constituent monosaccharides, glucose and galactose. In order to measure the presence of reducing sugars (glucose and galactose) dinitrosalicylate is added to stop the reaction and then produces a colour where the intensity changes on the presence of the products (reducing sugars). An experiment to investigate the rate of lactase was carried out as below. Before the experiment was started, samples for the standard curve were made to a volume of 1 ml using a 0.5 M glucose/0.5 M galactose solution. (a) Calculate the volume of the 0.5 M glucose/0.5 M galactose solution and H2O for each of the standards, where the final volume is 2000 µl. [5 marks] Write your answers in your booklet, DO NOT write on the exam paper. Glucose/galactose Concentration Volume of 0.5 M glucose/0.5 M galactose solution (µl) Volume of H2O (µl) Example table M glucose, 0.00 M galactose M glucose, M galactose M glucose, M galactose 0.04 M glucose, 0.04 M galactose 0.05 M glucose, 0.05 M galactose The standard curve was set up adding 1000 µl of a standard and 1000 and µl 1 M lactose solution to a test tube and mixed thoroughly. The samples were incubated at room temperature (20 o C) for 8 minutes and then 2000 µl of Dinitrosalicylate reagent was added to the tubes, which were then incubated at 100 o C for 5 minutes. The absorbance was measured using a spectrophotometer set to 540 nm, which was zeroed with distilled water. The results for the standard curve are shown in Table 1 below. Glucose/galactose Concentration 0M M M 0.04 M 0.05M (0.005M glucose/0.005m galactose) Abs 540nm Table 1. Results for the standard curve Section B Q29 continues on next page/...

9 9 Section B Q29 continued... (b) Plot a standard curve using these data using the graph paper provided. [10 marks] To investigate the rate of lactase activity, an experiment was set up as using varying concentrations of lactose. Tubes containing M; 0.01 M, 0.02 M, 0.03 M, 0.04 M and 0.05 M of lactose solution were incubated with 500 µl of lactase enzyme (total volume was 2000 µl) at room temperature (20 o C) for 8 minutes and then 2000 µl of Dinitrosalicylate reagent was added to the tubes before incubation at 100 o C for 5 minutes. The absorbance was then measured using a spectrophotometer as before. The results for the experiment are shown in Table 2 below: Substrate Conc (M) (in final reaction) Absorbance 540nm Table 2. Substrate Conc and absorbance (c) Using your standard curve, determine the concentration of glucose/galactose is present in each of the sample tubes after incubation with lactase. [5 marks] Write your answers in your booklet, DO NOT write on the exam paper. ` Lactose Conc (M) (in final reaction) Example table. Glucose/galactose M (d) Looking at the data from the experiment, what observations can be made? (e) The highest absorbance reading was for the reaction containing an initial lactose concentration of 0.05 M. Calculate the lactase rate of reaction in the sample tube containing 0.05 M lactose. Your answer should be given in the correct scientific notation and be expressed in mm min -1. [5 marks] Section B Q29 continues on next page/... TURN OVER

10 10 Section B Q29 continued... (f) The lactase enzyme present in humans has an optimal temperature of 37 o C. If the same experiment was repeated, but the samples were incubated at 37 o C and at 50 o C, how would this affect the lactase rate of reaction compared to the experiment carried out at room temperature (20 o C)? [3 marks] END OF SECTION B START YOUR ANSWER TO THE NEXT SECTION IN A NEW BOOKLET Section C begins on next page/...

11 11 SECTION C: ESSAY QUESTION ANSWER THIS SECTION IN A NEW BOOKLET Answer ONE question [30 marks] 30. With reference to its structure, describe the role of haemoglobin in the transportation of blood gases. 31. Discuss how species may respond to competition for resources within a named habitat. Give at least two examples to support your answer. 32. Discuss how muscles contract and explain the process whereby a nerve impulse causes muscle contraction. END OF PAPER

Organic Compounds. Compounds that contain CARBON are called organic. Macromolecules are large organic molecules.

Organic Compounds. Compounds that contain CARBON are called organic. Macromolecules are large organic molecules. Macromolecules 1 Organic Compounds Compounds that contain CARBON are called organic. Macromolecules are large organic molecules. 2 Carbon (C) Carbon has 4 electrons in outer shell. Carbon can form covalent