1. Which hormone stimulates the release of calcium from bones and increases blood calcium levels?

A. Parathyroid hormone (PTH)
B. Calcitonin
C. Growth hormone
D. Testosterone

Correct answer: A

Rationale: The correct answer is A: Parathyroid hormone (PTH). PTH is produced by the parathyroid glands and plays a crucial role in regulating calcium levels in the blood. When blood calcium levels are low, PTH is released to stimulate the release of calcium from bones, increase calcium absorption in the intestines, and reduce calcium loss in the kidneys. This process helps to maintain the necessary balance of calcium in the body. Calcitonin, on the other hand, works in opposition to PTH by decreasing blood calcium levels. Growth hormone primarily stimulates growth and development of tissues, while testosterone is a male sex hormone and does not directly impact calcium regulation.

2. What is the main component of bile, a substance that aids in fat digestion?

A. Proteins
B. Carbohydrates
C. Bile salts
D. Vitamins

Correct answer: C

Rationale: Rationale: Bile is a digestive fluid produced by the liver and stored in the gallbladder. Bile salts are the main component of bile that aid in the digestion and absorption of fats in the small intestine. Bile salts help emulsify fats, breaking them down into smaller droplets that can be more easily digested by enzymes. Proteins, carbohydrates, and vitamins are not the main components of bile and do not play a significant role in fat digestion.

3. The primary function of the placenta during pregnancy is to:

A. Produce insulin
B. Facilitate gas exchange between mother and fetus
C. Excrete waste products from the fetus
D. All of the above

Correct answer: D

Rationale: The correct answer is D, 'All of the above.' The placenta serves multiple crucial functions during pregnancy. It facilitates gas exchange between the mother and fetus, ensuring the transfer of oxygen and nutrients while removing carbon dioxide and waste products. Additionally, the placenta produces hormones like insulin that help regulate the mother's metabolism and support the development of the fetus. Therefore, the placenta plays a vital role in maintaining a healthy environment for the growing fetus by providing essential nutrients, removing waste, and regulating hormonal balance.

4. What does the term "net force" refer to in physics?

A. Total force acting on an object
B. Force due to gravity
C. Force in motion
D. Force of friction

Correct answer: a

Rationale: Net force is the vector sum of all forces acting on an object.

5. Cartilage is a flexible connective tissue found in the:

A. Center of long bones
B. Joints between bones
C. Muscle tissue
D. Walls of blood vessels

Correct answer: A

Rationale: Cartilage is a flexible connective tissue that is found in the joints between bones. It is a strong yet flexible tissue that cushions and supports the joints, allowing for smooth movement and reducing friction between bones. Cartilage is not typically found in the center of long bones, muscle tissue, or walls of blood vessels. Therefore, the correct answer is B: 'Joints between bones.'

6. The Minimum Inhibitory Concentration (MIC) of an antibiotic refers to:

A. The lowest concentration that kills bacteria
B. The dose required for 50% bacterial inhibition
C. The time it takes for an antibiotic to work
D. The spectrum of bacteria the antibiotic targets

Correct answer: B

Rationale: Rationale: A) The lowest concentration that kills bacteria is known as the Minimum Bactericidal Concentration (MBC), not the Minimum Inhibitory Concentration (MIC). MIC is the lowest concentration of an antibiotic that inhibits visible growth of bacteria. B) The MIC of an antibiotic is the concentration at which bacterial growth is inhibited by 50%. This concentration is used to determine the effectiveness of an antibiotic against a specific bacterium. C) The time it takes for an antibiotic to work is not described by the MIC. MIC is a measure of concentration, not time. D) The spectrum of bacteria the antibiotic targets is not defined by the MIC. The MIC value is specific to a particular antibiotic and bacterium, regardless of the spectrum of activity of the antibiotic.