Biological Science Revision Questions

1. What are the advantages of live attenuated vaccines? - response very strong - very efficient vaccine - long-lasting immunity (few doses required) 2. What are the disadvantages of live attenuated vaccines? - not suitable for immunocompromised patient - virus still alive can replicate - mutation = regain pathogenicity - alive = difficult to store 3. What are the ad- - suitable for immunocompromised patient vantages of inac- - can't mutate/regain pathogenicity tivated vaccines? - dead = so easier to store (opposite) 4. What are the disadvantages of inactivated vaccines? - not similiar to natural infections - not long lasting - more dosing required - usually induce humoral - not very efficient 5. Describe steps of the 'experiment' carried out by Edward Jenner that result in a vaccine against smallpox: - milkmade infected with cow pox - cow pus introduced to james - he contracts cow pox - scabs gained from smallpox patient - james inoculated with small pox scabs - does not suffer any symptoms, he's now protected he was protected from smallpox because his body triggered an immune from cowpox. this causes B cells to differentiate into plasma cells + memory cells - plasma cells produce antibodies - when he got smallpox, antigen similar to cowpox, body respond quickly 6. A patient that has - the kidneys are located in the abdominal cavity, behind suffered a car ac- the peritoneum, with the right kidney slightly lower than cident has an in- the left due to the presence of the liver. 1/4 jury in the kidneys caused by a rib. Could you please describe to a junior doctor the anatomical location of the kidney + potential caused of the kidney injury by the car crash: 7. A patient presents a problem of micturition incontinency. What are the physiological pathways that regulate the micturition reflex? - floating ribs are the last 2 pairs of ribs that are not attached to the sternum + can snap in a car accident (structural fat = protects the kidney, but not have functional fat) - may cause rib fracture that may lead to kidney injuries due to their close proximity. The force from the car crash can lead to ruptures of the kidneys - the micturition reflex is regulated by both sympathetic + parasympathetic pathways - when the bladder fills, stretch receptors send signals via afferent fibers to the sacral spinal cord - Parasympathetic fibers from the sacral spinal cord stimulate the detrusor muscle to contract + internal urethral sphincter to relax, allowing for voiding - Sympathetic fibers inhibit the detrusor muscle + stimulate the external urethral sphincter to maintain continence 8. Patient has suffered a severe cut in a blood vessel and is losing a lot of blood. How does this affect to his blood pressure? relationship between blood pressure + renin-angiotensin-aldosterone system - when a patient suffers a severe cut in a blood vessel, their blood pressure will drop due to decrease in blood volume - Juxtaglomerular cells are specialised cells located in the afferent arteriole near the glomerulus - When juxtaglomerular cells sense a decrease in blood pressure, they release renin, initiating the renin-angiotensin-aldosterone system - The kidneys release renin, which initiates the conversion of angiotensinogen to angiotensin I, which is then converted into angiotensin II - leading to vasoconstriction to help raise blood pressure back to normal levels. - Additionally, angiotensin II stimulates the release of 2/4 aldosterone, which promotes sodium and water retention to increase blood volume and pressure - BP = HR X SV BP = HR X SV X PR - an increase in peripheral resistance can increase blood pressure 9. A male patient - condoms = barrier method, prevent sperm from reaching the egg (reduces chance of fertilisation) comes to your pharmacy asking - vasectomy = surgical procedure, that prevents sperm advice about from reaching the semen what > By blocking the vas deferens, sperm are unable to mix with seminal fluid during ejaculation, this prevents sperm contraceptive methods he can from being ejaculated. use. Describe male contraceptive methods, explaining in detail the anatomy/physiology underlying your answer: 10. A pregnant mother comes to your pharmacy and tells you that she is being treated with 0.4mg/day of folic acid + she wants to know why this is happening. She is very worried that the folic acid could cause damage to the baby. - during pregnancy, folic acid is crucial for fetal development - it helps prevent neural tube defects like spina bifida - W3/4 of pregnancy, the neural tube forms in the embryo from the ectoderm - in the early stages, the ectoderm forms the neural plate, which then folds into the neural groove + eventually closes to create the neural tube - folic acid ensures proper neural tube formation + reducing the risk of birth defects 3/4 11. A patient with hypothyroidism is prescribed levothyroxine (T4) replacement therapy. Explain how levothyroxine functions in the body to manage hypothyroidism. Discuss the mechanism of action of levothyroxine at the cellular level + how it restores thyroid hormone level in patient with hypothyroidism - Levothyroxine is taken orally + is converted to the active form T3 in peripheral tissues - once inside the cell, T3 binds to thyroid hormone receptors in the nucleus, regulating gene expression + protein synthesis - this restores thyroid hormone level in the patient, improve metabolism etc. 4/4