How is the muscular system benefited by regular exercise?

Correct Answer: B

Rationale: Regular exercise is beneficial for the muscular system by improving muscle strength and endurance. Exercise helps to build and maintain muscle mass, increase muscle strength, and enhance muscle endurance. It does not decrease muscle mass, make muscles less flexible, or increase the risk of muscle tears when done properly. Therefore, the correct answer is improving muscle strength and endurance, as it aligns with the positive effects of regular exercise on the muscular system.

Correct Answer: C

Rationale: Estrogen is the hormone responsible for the characteristic changes experienced during puberty in females, such as breast development and menstruation. Estrogen plays a crucial role in the development of secondary sexual characteristics and the regulation of the menstrual cycle. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are primarily involved in the regulation of the menstrual cycle and ovulation. Progesterone, on the other hand, is important for preparing the uterus for pregnancy and maintaining pregnancy, but it is not the primary hormone responsible for the changes seen during puberty in females.

Correct Answer: C

Rationale: The correct answer is C: Skeletal muscle. Skeletal muscle is attached to bones and allows for voluntary movement, such as walking, running, and lifting objects. Smooth muscle, found in the walls of internal organs and blood vessels, is responsible for involuntary movements. Cardiac muscle is specific to the heart and controls involuntary contraction. Connective tissue, on the other hand, provides support and connects different structures in the body, but it is not responsible for voluntary movement like skeletal muscle.

Correct Answer: A

Rationale: Aerobic respiration is the process by which cells use oxygen to convert glucose into energy. This process occurs in the mitochondria of cells and is the most efficient way to produce energy during exercise. Anaerobic respiration and glycolysis are alternative pathways for energy production when oxygen is limited, typically occurring during high-intensity exercise. Lactic acid fermentation, on the other hand, occurs in the absence of oxygen and leads to the production of lactic acid, causing muscle fatigue and soreness.

Correct Answer: B

Rationale: Serotonin is a neurotransmitter that is associated with regulating mood, sleep, and memory. It plays a crucial role in maintaining emotional balance and is often a target in treating mood disorders like depression and anxiety. Serotonin also helps regulate sleep patterns and is connected to memory function. Dopamine (choice A) is more commonly linked to reward, motivation, and movement. Acetylcholine (choice C) is involved in muscle control and memory. Glutamate (choice D) is a major excitatory neurotransmitter in the brain but is not primarily associated with mood, sleep, and memory.