Correct Answer: A

Rationale: The correct answer is A: Somatic. The femoral, radial, and ulnar nerves are all part of the somatic nervous system, responsible for controlling voluntary movements and sensory input. These nerves innervate muscles and skin throughout the body, allowing conscious control of movements and sensations. The somatic nervous system is distinct from the autonomic nervous system, which regulates involuntary bodily functions. Choices B, C, and D are incorrect because the autonomic nervous system (B) is responsible for involuntary functions, while the sympathetic (C) and parasympathetic (D) divisions are subdivisions of the autonomic nervous system, not the somatic nervous system.

Correct Answer: B

Rationale: The correct answer is B because the nervous system communicates with the muscular system to control voluntary and involuntary muscle movements. The nervous system sends signals to the muscles, instructing them on how to respond to various stimuli in the environment. This communication allows for coordinated movement and responses to external and internal changes. Choice A is incorrect because muscles do not produce chemicals to feed the nerves. Choice C is incorrect because the nervous system does not release chemicals to remove waste from the muscles. Choice D is incorrect because the muscular system does not provide input for the nerves to make decisions.

Correct Answer: B

Rationale: The correct answer is B. Femur. The femur, also known as the thigh bone, is located in the human thigh. It is the longest and strongest bone in the human body, extending from the hip to the knee. The ulna, radius, and humerus, on the other hand, are bones found in the arm. Therefore, choices A, C, and D are incorrect as they are bones of the arm, not the thigh.

Correct Answer: B

Rationale: Schwann cells are a type of neuroglia found in the peripheral nervous system. They are responsible for producing the myelin sheath around axons of neurons, which helps with the conduction of nerve impulses. Therefore, Schwann cells are typically found in the nervous system. Choices A, C, and D are incorrect because Schwann cells are specifically associated with the nervous system and are not found in the digestive, skeletal, or muscular systems.

Correct Answer: A

Rationale: The correct answer is A. Vitamins are essential nutrients that the body needs in small amounts but do not provide energy like carbohydrates, fats, and proteins do. Carbohydrates, fats, and proteins are macronutrients that supply energy to the body when broken down during metabolism. Vitamins, on the other hand, play crucial roles in various bodily functions but are not a source of energy. They are essential for supporting growth, immune function, and overall health, but do not contribute directly to energy production. Choices B, C, and D are incorrect because carbohydrates, fats, and proteins are macronutrients that provide energy to the body when metabolized.