NUMS — Medical & Dental Entry Test
Take the NUMS Biology — Homeostasis, Support and Movement (Set 2): 30 multiple-choice questions (40 minutes) with instant scoring and a full answer…
What this test covers
The first 5 questions of this test, with the correct answer and explanation.
Q1. Marine bony fish live in water saltier than their body fluids. To osmoregulate they:
Answer: B. Drink seawater, excrete salts through gills and produce little urine
Explanation: Marine teleosts lose water by osmosis, so they drink seawater, actively secrete excess salt from gill chloride cells, and make small amounts of concentrated urine.
Q2. Freshwater fish face the problem of water entering their bodies by osmosis. They respond by:
Answer: D. Producing large volumes of dilute urine and actively absorbing salts at the gills
Explanation: Freshwater is hypotonic to the fish, so they remove excess water as copious dilute urine and take up ions actively at the gills.
Q3. The functional unit of the kidney is the:
Answer: A. Nephron
Explanation: Each kidney contains about a million nephrons, each performing filtration, reabsorption and secretion.
Q4. The efferent arteriole leaving the glomerulus is narrower than the afferent arteriole entering it. This arrangement:
Answer: B. Raises the hydrostatic pressure in the glomerulus, driving ultrafiltration
Explanation: Blood enters faster than it can leave, so pressure builds up in glomerular capillaries and forces fluid into Bowman's capsule.
Q5. About 65–80% of the filtered water and Na⁺, and nearly all of the filtered glucose and amino acids, are reabsorbed in the:
Answer: C. Proximal convoluted tubule
Explanation: The PCT, with microvilli and many mitochondria, reabsorbs all glucose and amino acids and most of the water and salts.
Take the timed test (free, no sign-up) to see your score and the answer and explanation for every question.
Q6. The glomerular filtration rate is 125 cm³ per minute and urine is produced at 1 cm³ per minute. What percentage of the filtrate is reabsorbed?
Q7. Aldosterone acts on the distal tubule and collecting duct. A patient with an adrenal tumour secreting excess aldosterone would most likely show:
Q8. ADH increases water reabsorption in the collecting duct by:
Q9. Drinking alcohol causes increased urine output because alcohol:
Q10. In the loop of Henle, the descending limb is permeable to water. As filtrate moves down it into the medulla, the filtrate becomes:
Q11. Urea is produced in the liver from:
Q12. Freshwater fish and tadpoles can excrete nitrogenous waste as ammonia because:
Q13. In kidney transplantation, the recipient is given immunosuppressant drugs for life. This is because:
Q14. A person enters a very hot room. Which combination of responses would the hypothalamus bring about?
Q15. Animals such as lizards that regulate body temperature mainly by behaviour (basking or seeking shade) are called:
Q16. Fever during infection is caused by chemicals called pyrogens which:
Q17. Which of the following is an example of negative feedback?
Q18. Under the microscope, the dark A-band of a skeletal muscle sarcomere corresponds to the:
Q19. During contraction of a skeletal muscle sarcomere, which pair of measurements both decrease?
Q20. In the cross-bridge cycle, ATP is needed for:
Q21. When calcium binds to troponin, contraction can begin because:
Q22. Smooth muscle differs from skeletal muscle because it is:
Q23. During prolonged vigorous exercise, muscles fatigue. One main cause is:
Q24. Tendons connect:
Q25. The elbow and knee are examples of hinge joints. The joint between the atlas and the axis vertebrae that allows the head to turn side to side is a:
Q26. In osteoarthritis, the joint becomes painful and stiff mainly because:
Q27. Bone-forming cells that secrete the matrix of bone are called:
Q28. A broken bone heals faster in a child than in an elderly person. Which is the best explanation?
Q29. Wood is strong and rigid mainly because xylem vessels and fibres have walls thickened with:
Q30. When a plant is not watered for several days, its leaves wilt because: