BIOL121-Human Biological Science
Case Study
Gustav is a 50yo male who has made an appointment to see his GP for his biannual health check. He tells the doctor that he has been feeling “a bit puffed” walking around the course during his weekly game of golf. Gustav has gained nine kilos since his 40th birthday, and his waist measurement has expanded. He laughs this off as “middle aged spread”, and says his wife tells him he needs to watch what he eats and drink less alcohol. He works as a journalist for a local paper, which he has been finding very stressful of late, and spends a lot of his time in the office sitting in front of a computer, snacking.
Gustav has recently decided to give up smoking, and wonders if this has contributed to his weight gain. He regularly chews nicotine gum when he craves a cigarette.
Physical examination:
Urinalysis:
Question 1
A. Gustav is late for work and the lift is broken; he must run up 6 flights of stairs to make it on time. Describe the changes in volume and pressure that will be occurring in Gustav’s chest cavity to achieve inhalation during his run. Explain why these changes are occurring, and the effects upon airflow.
B. Describe the gas exchange occurring between Gustav’s blood and the skeletal muscle in his legs. Will the rate of gas exchange change during exercise? Explain your answer.
Question 2
A. Which ANS response would you expect to dominate during Gustav’s run up the stairs? Explain your answer.
B. Considering Gustav’s prolonged psychological stress, explain the role of cortisol and the hypothalamic-pituitary axis in his body’s likely response to these stresses.
Question 3
A. Describe the role of the kidneys in maintaining fluid balance with reference to the role of antidiuretic hormone (ADH). Is Gustav at risk of not maintaining homeostatic fluid mechanisms? Why/why not?
B. What is a urinalysis and what is its significance for this case? With respect to the blood component of Gustav’s urinalysis result, and using your knowledge of normal kidney function, would you expect this result? Why/why not?
Question 4
A. Consider Gustav’s blood pressure result and discuss whether the mean arterial pressure is likely to be varied from normal. In your answer you must include reference to a change in vessel length with his increasing weight and briefly mention the consequences of any change in BP upon kidney function.
B. In this circumstance, do you think the renin-angiotensin-aldosterone system or natriuretic peptides will dominate in the maintenance of Gustav’s blood pressure. Discuss the role of your chosen system in blood pressure homeostasis to explain your answer
Question 5
A. Gustav suffered a significant haemorrhage during his appendectomy and required a blood transfusion. Which blood type(s) could have been safely administered to Gustav? Explain the potential consequences if Gustav had been administered B- blood.
B. Gustav has been found to have low platelet levels. How would this effect the ability of his blood to clot? Explain your answer.