1. Saliva contains an enzyme that breaks down carbohydrates. What is the name of this enzyme?

A. Pepsin
B. Amylase
C. Lipase
D. Trypsin

Correct answer: B

Rationale: The correct answer is B: Amylase. Saliva contains the enzyme amylase, which is responsible for breaking down carbohydrates into simpler sugars like maltose and glucose. Pepsin (A) is an enzyme found in the stomach that breaks down proteins. Lipase (C) is an enzyme that breaks down fats, and trypsin (D) is another enzyme that breaks down proteins, but both of these are not found in saliva. Knowing the function of amylase in saliva helps in the digestion of carbohydrates, making it the correct answer.

2. Diabetic nephropathy, a complication of diabetes, affects the:

A. Ureters
B. Bladder
C. Urethra
D. Nephrons

Correct answer: D

Rationale: The correct answer is D: Nephrons. Diabetic nephropathy is a type of kidney disease that occurs as a complication of diabetes. It specifically affects the nephrons, which are the functional units of the kidneys responsible for filtering waste and excess fluids from the blood to produce urine. Damage to the nephrons can lead to kidney failure and other serious complications in individuals with diabetes. Therefore, understanding the impact of diabetes on the nephrons is crucial for managing diabetic nephropathy effectively.

3. The main function of the nephrons is to:

A. Store urine
B. Filter blood and remove waste products
C. Produce hormones
D. Control blood pressure

Correct answer: B

Rationale: The correct answer is B: 'Filter blood and remove waste products.' Nephrons are the functional units of the kidneys responsible for filtering blood to remove waste products, excess ions, and water, while reabsorbing essential substances like glucose and amino acids. This process forms urine, which is stored in the bladder before being excreted. Options A, C, and D are incorrect because nephrons do not store urine, produce hormones, or directly control blood pressure; although the kidneys do play a role in long-term blood pressure regulation through mechanisms like the renin-angiotensin-aldosterone system.

4. Which factor affects the kinetic energy of an object the most?

A. The object's mass
B. The object's velocity
C. The object's displacement
D. The object's potential energy

Correct answer:

Rationale: Kinetic energy is directly proportional to the square of an object's velocity.

5. Which type of glial cell provides structural support and insulation for neurons in the central nervous system?

A. Schwann cells
B. Astrocytes
C. Oligodendrocytes
D. Microglia

Correct answer: C

Rationale: The correct answer is C: Oligodendrocytes. Oligodendrocytes are a type of glial cell found in the central nervous system that provide structural support and insulation for neurons by forming myelin sheaths around axons. Schwann cells, on the other hand, are found in the peripheral nervous system. Astrocytes play a role in nutrient transfer and maintaining the blood-brain barrier. Microglia are responsible for immune defense and clearing debris in the CNS. Therefore, oligodendrocytes are specifically responsible for providing structural support and insulation for neurons in the central nervous system.

6. Which of the following is the main function of the liver?

A. To produce bile, which helps digest fats
B. To store energy in the form of glycogen
C. To produce proteins that help to clot blood
D. To detoxify harmful substances in the body

Correct answer: D

Rationale: Rationale: A) The liver does produce bile, which helps in the digestion of fats, but this is not its main function. Bile is stored in the gallbladder and released into the small intestine to aid in the digestion and absorption of fats. B) While the liver does store energy in the form of glycogen, this is not its main function. Glycogen is a form of glucose storage that can be broken down into glucose when the body needs energy. C) The liver does produce proteins that help to clot blood, such as fibrinogen and prothrombin, but this is not its main function. These proteins are essential for the blood clotting process to prevent excessive bleeding. D) The main function of the liver is to detoxify harmful substances in the body. The liver processes and removes toxins, drugs, alcohol, and other harmful substances from the bloodstream, making them less harmful and