QUESTION 1
Fill in the blank boxes to complete TWO rows of your choice in the following table, which summarises the name, location and function of a variety of cells throughout the body. The first line is completed as an example of the level of detail required. (1 mark/line; 2 marks total) Cell name Where would you usually expect to find this cell type? (be specific) What is its job? (or primary role) Parietal cell Gastric glands in the stomach. Secrete intrinsic factor and HCl Production of melanin to protect underlying tissue from harmful UV radiation. Spontaneously depolarise to trigger contraction of cardiac muscle. Establishes the heart rate. Osteocyte Contains large quantities of haemoglobin, enabling it to bind and transport respiratory gases. Chief cells 2
QUESTION 2 Complete each of these sentences with a word or phrase that best describes the outlined scenario. Write the word or phrase in the blank column. (0.5 mark each – total 3 marks) The pressure driven movement of water and solutes from the glomerulus into the Bowman’s capsule is best-described as ________________. The movement of glucose into cells via glucose transporter proteins is an example of ________________. Cells lining the small intestine continue to absorb glucose, even when glucose concentrations are much higher in the cells compared to the intestinal contents. This is because the glucose is entering the cell via the process of ________________. When a micelle contacts the intestinal epithelium, the fatty acids move into the cells via ________________. In the thick ascending limb of the nephron loop, Na+ and Clare removed from the tubular fluid via ________________. ADH facilitates the insertion of aquaporins into the apical plasma membranes of the distal convoluted tubules and collecting system. These channel proteins allow water to move out of the tubular fluid via ________.
QUESTION 3 The following paragraph refers to muscle contraction. Fill in each of the blanks to complete the paragraph using terms from the list provided. More words than necessary are provided, and terms may be used more than once. (0.5 mark each – total 3 marks) The action potential spreads along the _______________, until it reaches a T-tubule. The action potential continues down the T-tubule where it triggers the release of __________ from the ________________. This exposes binding sites on __________. __________ heads bind to the exposed sites on __________ to form cross-bridges. • Na+ • sarcoplasm • mitochondria • K+ • sarcolemma • Golgi apparatus • Ca2+ • Mg2+ • sarcoplasmic reticulum • sarcomere • myofibril • myosin • actin • nucleus • myofilament 3
QUESTION 4 Which type of immunity is expressed in the following scenarios? Choose between: • Non-specific (first line defence) • Specific (antibody-mediated) • Specific (cell-mediated immunity) (0.5 mark each – total 2 marks) Scenario Type of immunity Bacterial septicaemia (bacterial contamination in systemic circulation) The pH of hydrochloric acid in the stomach acts to destroy ingested bacteria A liver cell mutates and becomes cancerous A virus multiplies inside the epithelial cells in your throat.
QUESTION 5 Antidiuretic hormone and aldosterone are both hormones that act to conserve water in the body. Fill in the following table for each of these hormones. (0.5 mark each – total 4 marks) Antidiuretic hormone Aldosterone Where is this hormone synthesized? Which gland secretes this hormone? Facultative or obligatory reabsorption? Mechanism of action (how does it work?) 4
QUESTION 6 The results of dipstick urinalysis of two urine samples are listed below. Sample 1 belongs to a 16-year-old male ‘gamer’ who has locked himself in his room all weekend to play computer games (he didn’t really even come out to eat or drink). Sample 2 belongs to a 22-year-old female triathlete who is careful with her diet, hydration, and almost exercises to excess. For each parameter, fill in the normal values. (Hint: Refer to the Week 10 laboratory activity to get you started). Parameter Normal values Sample 1 Sample 2 Colour Dark yellow Reddish tinge Glucose – – Bilirubin – Ketones ++ – Specific gravity 1.039 1.010 Blood – ++ pH 5.5 6.0 Protein – ++ Nitrite – – Leukocytes – – A. What personal protective equipment should be worn when handling someone else’s urine? Explain. (1 mark) 5 Choose ONE of the samples above and answer the following questions in the space below. B. Compare the normal and sample values. List any abnormalities you observe in the section below. Are they higher or lower than normal? (1 mark) C. Give a situation in which you might expect to see these changes in an otherwise healthy individual. (1 mark) D. What might have been happening in the nephron to cause these abnormal results? Explain your observed abnormalities by linking them with the part of the nephron involved and the process involved (ie filtration, secretion or reabsorption). Ensure that any relationships between the abnormal readings are made clear in your response. (2 marks) Chosen sample: B C D
QUESTION 7 Why is injury to the medulla oblongata frequently fatal? (2 marks) 6
QUESTION 8 A. Indicate which phase of haemostasis is depicted in each of the pictures below. (1.5 marks total) B. Provide a brief description of each phase, using the diagrams to help explain your answer. (3 marks total) Picture Name of phase Description of phase 7
QUESTION 9 1. Write the name of each vessel type pictured in the table below in the corresponding box. 2. For TWO of the vessels, complete the row to include: a. the key identifying feature of that vessel type b. the layer in which this key identifying feature is found c. indicate whether the key identifying feature is notable because it is present in large amounts OR present in small amounts OR absent d. how this key identifying feature relates to the function of that vessel. (0.5 marks for a-c and 1 mark for d; total 5 marks) Picture Vessel type? (a) Identifying feature? (b) Layer of vessel? (c) Notable because… (d) Relates to vessel function because… Name: Student number: 8
QUESTION 10 Complete the table below to outline TWO feedback mechanisms (blood pressure and another of your choice). Your second mechanism must be one that is mediated by a hormone of the hypothalamuspituitary axis; record both the mechanism and the hormone in the table below. For both blood pressure and your chosen mechanism, you will need to (a) describe the main role of each feedback mechanism, (b) identify the receptor, control centre and effector and (c) specify whether this is a positive or negative feedback mechanism. Body temperature is provided as an example of the level of detail required. (0.5 marks each – 5 marks total) Mechanism: Body temperature Blood pressure Mechanism: Hormone: Role: Maintaining body temperature within narrow, optimal limits Receptor: Thermoreceptor in skin Control centre: Brain (hypothalamus) Effector: Sweat glands and arterioles near the skin. (NB This is one of a number of possible answers.) Positive or negative feedback? Negative 9
QUESTION 11 Duchenne muscular dystrophy (DMD) is recessive sex-linked disorder, which causes muscle degeneration and premature death. A couple is pregnant with a boy and neither have DMD. The father’s family has no history of DMD, but the mother is unsure of her genetic family history as she was adopted. The mother decides to take advantage of some of the new genomic screening tests and learns information about a large number of her genes. She finds that she is a carrier of the DMD affected allele. (3 marks total) A. What is the mother’s genotype? Explain your reasoning. (1 mark) B. What is the father’s genotype? Explain your reasoning. (1 mark) C. What is the likelihood of the male foetus having DMD? Use a punnet square to explain your answer. (1 mark) 10
QUESTION 12 Insert the correct term in the summary about digestion using the suggested labels below. Not all terms are suitable and may be used only once. (0.5 marks each – 6 marks total) Proteins are digested by ______________ at an _____________ pH in the stomach. Further protein digestion is achieved by pancreatic _______________ in the duodenum and completed at the microvilli by brush border enzymes to liberate ________________ for absorption. Digestion in the small intestine requires a pH that is _____________. Intestinal pH is adjusted by secretion of _______________ produced by the liver and _______________ produced by the pancreas. Pancreatic enzymes show specificity for their substrates. Pancreatic ______________ digests carbohydrates to __________________ and trisaccharides. Brush border enzymes complete carbohydrate digestion to __________________ for absorption. Pancreatic ______________, together with bile salts acting as an emulsifying agent, digest fats to monoglycerides and free fatty acids. Monosaccharides and amino acids are absorbed into the intestinal capillaries. Monoglycerides and free fatty acids are absorbed into the ____________________. o Acidic o Cellulose o Lymphatic vessels o Neutral o Starch o Lipase o Alkaline o Dissacharides o Pepsin o Amylase o Monosaccharides o Peptidase o Carbonic anhydrase o Insulin o Bile salts o Permease o Hepatic portal vein o Bicarbonate
QUESTION 13 Describe the changes in volume and pressure inside the chest cavity during a normal exhalation. Explain why these changes are occurring, and the effect upon airflow. (2 marks) 11
QUESTION 14 The figure below illustrates inspiration and expiration. Refer to this figure to answer the following questions. (0.5 marks each – 3 marks total) Question Answer Contraction of which muscle/s produces the movement labelled “1”? Contraction of which muscle/s produces the movement labelled “2”? At label “3”, is pressure outside greater than or less than pressure inside the lungs? Is the pressure in the space labelled “4”, higher or lower compared to the atmospheric pressure? At label “8”, is pressure outside greater than or less than pressure inside the lungs? Name any ONE muscle that contracts to cause the extra movement required when you need to expire forcefully (indicated by the arrows labelled “6” and “7”).
QUESTION 15 Regarding ventilation, which process is active – inhalation or exhalation? Explain your answer. (1 mark) 12
QUESTION 16 A young child presents at the hospital with watery and explosive diarrhoea. Her father explains that they have just arrived home from India. Although the family were careful to consume well-cooked food and bottled water, the toddler was given an icy slushie at Delhi airport. Stool samples were collected and lab cultures were completed. The bacteria, Salmonella typhi was shown to be present. Consider this story in relation to microbiology principles, and complete the circle of infection by identifying the infectious agent, the reservoir, the mode of transmission and the portal of entry. (0.5 marks each – 2 marks total) Infectious agent ____________________ Reservoir _________________ Mode of transmission _________________________ Portal of entry ___________________________ Susceptible host young child – immature immune system 13
QUESTION 17 Relate tissue structure to function. A. Describe the type of epithelium you would expect to find in each of the locations listed below. (0.5 marks each – total 1.5 marks) B. How does the structure of this epithelium enable it to best perform its function (ie its ‘job’)? The first line is completed as an example. (1 mark each – total 3 marks) Location Type of epithelium Relate structure to function Bladder Transitional epithelium Permits repeated cycles of stretching and recoiling. This allows the bladder to cope with large changes in volume (ie stretch as it fills with urine, and recoil upon micturition). Alveoli Trachea Jejunum 14
QUESTION 18 The paragraph below relates to this graph, which describes changes in membrane potential over time. Fill in each of the blanks to complete the paragraph using terms from the list provided. More words than necessary are provided, and terms may be used more than once. (0.5 marks each – 4 marks total) During _________________________, the __________________of the cell is 70 mV more negative than the ___________________of the cell. When a stimulus is applied, the membrane potential must reach __________________ in order for an Action Potential to be fired. At the start of an Action Potential, Na+ channels open and Na+ ion __________________the cell. This phase is called ___________________. Which number indicates the point where a stimulus is applied? _________________ The ____________________ is the period of time in which the nerve membrane can start another action potential only if a much greater stimulus than usual is applied. • Na+ • negatively • peak action potential • K+ • positively • absolute refractory period • Ca+ • repolarisation • relative refractory period • inside • depolarisation • +35 mV • outside • enter • exit • hyperpolarisation • resting membrane potential • -70 mV • -55 mV