1. Which of the following is the primary excretory organ in humans?
Answer:
Explanation:
Kidneys are the primary excretory organs in humans responsible for filtering and eliminating waste products.
2. Urea is produced in the:
Answer:
Explanation:
Urea is produced in the liver from the breakdown of amino acids.
3. The functional unit of the kidney is called:
Answer:
Explanation:
Nephrons are the functional units of kidneys responsible for filtering blood and forming urine.
4. Which of the following is NOT a method of excretion in plants?
Answer:
Explanation:
Photosynthesis is a process of producing food, not excretion. Guttation, respiration, and transpiration are methods plants use to excrete waste.
5. Which part of the nephron is involved in the selective reabsorption of filtered substances?
Answer:
Explanation:
The proximal convoluted tubule is responsible for the reabsorption of vital substances from the filtrate.
6. The removal of metabolic wastes from the body is termed:
Answer:
Explanation:
Excretion refers to the removal of metabolic wastes from the body.
7. Uric acid is the chief nitrogenous waste of:
Answer:
Explanation:
Birds excrete uric acid as their primary nitrogenous waste, which conserves water.
8. Which blood vessel brings impure blood to the kidneys?
Answer:
Explanation:
The renal artery carries impure blood to the kidneys for filtration.
9. In which part of the kidney is urine collected before it enters the ureters?
Answer:
Explanation:
The renal pelvis collects urine from the renal pyramids before it enters the ureters.
10. Excessive sweating can lead to a decrease in the body's level of:
Answer:
Explanation:
Sweating leads to a loss of salt and water from the body.
11. Which of the following helps in osmoregulation?
Answer:
Explanation:
Kidneys play a vital role in osmoregulation, maintaining the body's internal salt and water balance.
12. Which of the following animals excrete ammonia?
Answer:
Explanation:
Many aquatic animals, like fish, excrete ammonia, which is highly soluble in water.
13. Dialysis is a method used to assist in kidney function for patients with:
Answer:
Explanation:
Dialysis is a treatment used to mimic kidney function in patients with renal (kidney) failure.
14. The yellowish color of urine is due to a pigment called:
Answer:
Explanation:
Urochrome is the pigment responsible for giving urine its characteristic yellow color.
15. The urine of a diabetic patient may contain:
Answer:
Explanation:
Diabetic patients may have glucose in their urine due to their body's inability to regulate blood sugar levels effectively.
16. Which of the following is NOT a function of the kidney?
Answer:
Explanation:
Kidneys do not play a role in the digestion of food.
17. The majority of water reabsorption in the nephron occurs in the:
Answer:
Explanation:
The proximal convoluted tubule is where most of the water reabsorption occurs.
18. Malpighian tubules are excretory organs in:
Answer:
Explanation:
Malpighian tubules are excretory organs found in insects.
19. Which of the following processes in the nephron is an active process requiring energy?
Answer:
Explanation:
Reabsorption in the nephron is an active process that requires energy to transport substances against their concentration gradients.
20. The hormone that increases the reabsorption of water in the collecting ducts of the nephron is:
Answer:
Explanation:
Vasopressin or Antidiuretic Hormone (ADH) acts on the collecting ducts, leading to the reabsorption of water and concentration of urine.