MPHY202P 2017-18 main 1 TURN OVER Answer ALL THREE questions in Section A and All TWO questions in section B The numbers in the right-hand margin indicate the provisional allocation of maximum marks per sub-section of a question. SECTION A 1) Identify which of the tissue samples in Figure 1 shows: a) muscle b) connective tissue c) Nervous d) Epithelial In each case state its main function/role. [7 marks] Figure 1 4 tissue types (http://www.nlm.nih.gov/medlineplus/ency/imagepages/8682.htm [Public domain] (modified) 2) Sketch the Urinary system, labelling its main parts [6 marks] 3) State the function of the following parts of a joint (Figure 2): a) Bone b) Muscle c) Synovial fluid d) Tendon e) Cartilage f) Ligament g) Joint capsule Figure 2 generic joint By Madhero88 (Own work Info sites 1 2 3) [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons) [7 marks] MPHY202P 2017-18 main 2 CONTINUED SECTION B 4) Osteoporosis An elderly woman trips whilst out shopping and has a suspected fracture to her wrist. X-rays taken at hospital confirm that one of the long bones is broken, but also indicate that she has Osteoporosis. Osteoporosis is a condition characterised by an excessive loss of bone density. Some loss is a normal part of aging, but it occurs faster in some people than others. a) Name the two long bones in her lower arm. [1 marks] Figure 3 shows cross sectional images (plane not specified, probably anterior coronal) of vertebrae, from two subjects. Figure 3 By Turner Biomechanics Laboratory (http://www.osseon.com/osteoporosis-overview/) [CC0], via Wikimedia Commons (modified) b) Identify which image (Figure 3 i or ii) is of healthy bone, and which shows signs of osteoporosis. Explain your reasoning. [1 marks] c) Describe, using standard anatomical language, where vertebra are found, relative to: i) Other vertebra ii) The whole body iii) The Cranium iv) The Scapulars [4 marks] d) Sketch the shape of one vertebra, showing transverse and sagittal planes, through the mid line. [3 Marks] e) Describe the function(s) of the vertebrae (as a combined system) and relate these to their shape and composition. [4 marks] f) Consider the likely impact of everyday forces and stresses on vertebrae and thus deduce the direct physical consequences of an accumulation of vertebral micro fractures. MPHY202P 2017-18 main 3 TURN OVER [4 marks] Research shows that people with reduced levels of oestrogen or testosterone, relative to peers of the same gender, are at greater risk of osteoporosis. g) What are oestrogen and testosterone are examples of Generically, where are they found in the body and what types of role do they have. [3 marks] h) Deduce a plausible mechanism for the link between oestrogen/testosterone levels and osteoporosis. Explain your logic. [1 marks] On discovering that the woman probably tripped because she did not see the raised paving slab, she was advised to have her eyes tested. She was found to have age related macular degeneration. The macular is the central region of the retina. i) Describe, with aid of labelled diagrams i) The function and structure of the macular. [3 marks] ii) The location of the macular within the eye. [3 marks] j) Deduce the visual symptoms associated with macular degeneration. Explain your reasoning. [3 marks] 5) Sickle cell disease (SCD) is a recessive inherited condition, which affects red blood cells. It is most common among people of African or Caribbean origin, indeed of the ~40000 infants annually who are born with this condition, three quarters live in sub-Saharan Africa (SSA). Carriers of SCD are described as having sickle cell trait (SCT). Various population studies have shown that, in SSA 50-90% of children with SCD die before they are 5. However, there is evidence that having SCT confers increased survival with respect to the most serious form of malaria. The mechanisms behind this have not yet been confirmed. In people with SCD, some of their blood cells are miss-shaped. Figure 3Figure 4 shows a cross- section through a typical sickle cell, and a number of them in a blood vessel. Part of the role of the spleen is to filter the blood, removing abnormal shaped cells. This can damage the spleen reducing its ability to carry out its other functions. Figure 4 Derived from image by Diana grib (Own work) [CC BY-SA 4.0 (http://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons MPHY202P 2017-18 main 4 CONTINUED Figure 5 By Cancer Research UK (Original email from CRUK) [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons a) Name parts i-v on Figure 5. What body system are they a part of (note: iii is inside another body structure, and just one example of that structure has been drawn). [3 Marks] b) Describe the function of normal red blood cells and with the aid of a labelled diagram, describe how the structure of normal red blood cells is well suited to this. [3 Marks] c) Deduce the symptoms a patient is likely to exhibit if a high proportion of blood cells are removed by the spleen Describe the physiological basis for these symptoms. [2 Marks] d) Describe how the abnormal cells differ from normal cells and deduce the other likely functional consequences and resultant symptoms (i.e. unrelated to the spleen). Explain you reasoning. [3 Marks] e) Describe, with reference to DNA and Meiosis (Figure 6), how conditions are inherited, naming the relevant cellular structures. [6 Marks] Figure 6 Meiosis (Ali Zifan [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons) f) Calculate the probability that a child born to patients who both have sickle cell trait will: i) inherit sickle cell disease ii) inherit sickle cell trait iii) be completely free from the condition. In each case show your logic/workings. [3 Marks] Malaria is a disease characterised by cycles of high grade fevers and chills with shivering, but severe and life threatening complications can occur. It is caused by a parasite that lives in the blood, and is transmitted between humans by a type of mosquito which can only breed in hot countries. MPHY202P 2017-18 main 5 END of PAPER Figure 7 Comparison of the distribution of malaria (left) and sickle-cell trait (right). By Anthony Allison (Original work by Anthony Allison) [CC0], via Wikimedia Commons g) Using the information above, deduce a plausible explanation for the distribution of SCT seen in the right hand map of Figure 3. [2 marks] h) Mosquitoes feed on human blood, to do so undisturbed they inject a local anaesthetic in the area. Describe the mechanism by which we would otherwise detect their presence. [2 marks] i) ě ∥ ě ě [2 marks] j) Occasionally a blood transfusion is necessary to treat SCD. People with blood group O have no A or B antigens and so are sometimes cal ě ě t are antigens and why do they need to be considered before administering a blood transfusion [4marks]
