1. Muscle soreness after exercise is often caused by microscopic tears in muscle fibers. This is called

A. Atrophy
B. Hypertrophy
C. Dom (Delayed Onset Muscle Soreness)
D. Spasm

Correct answer: C

Rationale: Muscle soreness after exercise is commonly caused by microscopic tears in muscle fibers, leading to a condition known as Delayed Onset Muscle Soreness (DOMS). Atrophy refers to the shrinking of muscle due to inactivity or lack of use, which is not the cause of muscle soreness after exercise. Hypertrophy is the increase in muscle size through exercise, not related to muscle soreness. Spasm is a sudden, involuntary muscle contraction unrelated to the micro-tears that cause muscle soreness. Therefore, the correct answer is C, DOMS, as it specifically addresses the micro-tears in muscle fibers that result in post-exercise soreness.

2. Which structure surrounds individual muscle fibers, providing support and aiding in the transmission of force generated during muscle contraction?

A. Tendon
B. Endomysium
C. Perimysium
D. Epimysium

Correct answer: b

Rationale: The correct answer is B: Endomysium. Endomysium is the connective tissue layer that surrounds individual muscle fibers within a muscle. It plays a crucial role in supporting the muscle fibers and aiding in the transmission of force generated during muscle contraction. Tendons (option A) connect muscle to bone and do not surround individual muscle fibers. Perimysium (option C) surrounds bundles of muscle fibers, while epimysium (option D) envelops the entire muscle. Therefore, endomysium is specifically responsible for surrounding and supporting individual muscle fibers, making it the most fitting answer.

3. What is the protective fluid that surrounds the brain and spinal cord?

A. Blood
B. Cerebrospinal fluid
C. Myelin sheath
D. Insulin

Correct answer: B

Rationale: The correct answer is B: Cerebrospinal fluid. This fluid acts as a cushion for the brain and spinal cord, providing protection from impacts. Blood is essential for transporting nutrients and oxygen, but it does not directly surround or protect these vital nervous system structures. Myelin sheath is a fatty substance that insulates nerve fibers, not the fluid surrounding the nervous system. Insulin is a hormone involved in regulating blood sugar levels and is not related to protecting the brain and spinal cord.

4. What is the primary hormone released by the parathyroid glands?

A. Insulin
B. Calcitonin
C. Parathyroid hormone (PTH)
D. Thyroxine

Correct answer: C

Rationale: The primary hormone released by the parathyroid glands is Parathyroid hormone (PTH), which plays a crucial role in regulating calcium levels in the body. Insulin is produced by the pancreas to regulate blood sugar levels and is unrelated to the parathyroid glands. Calcitonin is produced by the thyroid gland and helps regulate calcium levels but is not the primary hormone released by the parathyroid glands. Thyroxine is a hormone produced by the thyroid gland that regulates metabolism and is also not released by the parathyroid glands. Therefore, the correct answer is C: Parathyroid hormone (PTH).

5. Newton's rings are a visual demonstration of:

A. Diffraction
B. Doppler effect
C. Polarization
D. Thin-film interference

Correct answer: D

Rationale: Newton's rings are a series of concentric colored rings observed when light is reflected between a spherical surface and a flat surface. This phenomenon is a result of thin-film interference, which occurs due to the varying thickness of the air gap between the surfaces. The interference of light waves results in constructive and destructive interference, leading to the formation of the rings. Diffraction, the bending of light around obstacles, is not the cause of Newton's rings. The Doppler effect involves the change in frequency of waves due to motion and is not relevant in this context. Polarization refers to the orientation of electromagnetic waves, which is not the primary factor in the formation of Newton's rings. Therefore, the correct answer is D: Thin-film interference.

6. A lampshade is shaped like a frustum of a cone, with base diameters of 20cm and 10cm and a height of 15cm. What is its volume?

A. 625 cu cm
B. 1250 cu cm
C. 1875 cu cm
D. 2500 cu cm

Correct answer: C

Rationale: This requires dividing the frustum into two cones and calculating their individual volumes before subtracting them. The formula for a cone frustum involves the radii of both bases and the height.