What is the primary function of the lymphatic system?

Correct Answer: B

Rationale: The correct answer is B: Remove carbon dioxide from the body. The primary function of the lymphatic system is to return excess tissue fluid to the bloodstream and assist in the body's defense against infections by filtering out harmful pathogens and foreign particles. Choices A, C, and D are incorrect because transporting oxygen to cells is mainly done by the circulatory system, hormone production is primarily carried out by endocrine glands, and nutrient transport is also a function of the circulatory system and the digestive system, not the lymphatic system.

Correct Answer: B

Rationale: The small intestine is the primary site for nutrient absorption in the digestive system. It is responsible for absorbing nutrients from the digested food into the bloodstream for distribution throughout the body. Therefore, the correct function of the small intestine is to absorb nutrients. Choice A is incorrect because the gallbladder stores bile, not the small intestine. Choice C is incorrect because the digestion process primarily occurs in the stomach and small intestine. Choice D is incorrect because while the small intestine does play a role in enzyme production, its primary function is nutrient absorption.

Correct Answer: C

Rationale: The correct answer is the Appendix. The appendix is now known to play a role in the immune system by housing beneficial bacteria that aid in maintaining gut health and supporting immune responses. This organ contributes to overall immune function. Choices A, B, and D are incorrect as the heart, bronchi, and esophagus are not primarily associated with the immune system.

Correct Answer: B

Rationale: The adrenal glands function to produce hormones such as adrenaline and cortisol. These hormones play essential roles in regulating metabolism, immune response, and the body's response to stress. Therefore, the correct answer is that the adrenal glands produce hormones. Choices A, C, and D are incorrect as regulating blood sugar is primarily done by the pancreas, producing red blood cells is the function of the bone marrow, and filtering blood is carried out by the kidneys, not the adrenal glands.

Correct Answer: A

Rationale: The correct answer is A: To secrete digestive enzymes. The pancreas is responsible for secreting digestive enzymes that aid in breaking down carbohydrates, fats, and proteins in the small intestine, facilitating the process of digestion. Choice B is incorrect because the pancreas does not store bile; that is primarily the function of the gallbladder. Choice C is incorrect as the absorption of nutrients mainly occurs in the small intestine, not the pancreas. Choice D is incorrect as the transport of glucose is primarily regulated by insulin produced in the pancreas, but this is not the main role of the pancreas in digestion.

Correct Answer: A

Rationale: The primary function of the nervous system is to transmit signals and coordinate body activities. It controls and regulates body functions by sending and receiving signals between different parts of the body, enabling responses to internal and external stimuli. This intricate network allows for communication between the brain, spinal cord, and the rest of the body, ultimately facilitating movement, sensation, thoughts, and various bodily functions. Choices B, C, and D are incorrect as they do not represent the primary function of the nervous system. Fighting infections is primarily the role of the immune system, producing hormones is the function of the endocrine system, and regulating body temperature involves mechanisms of thermoregulation within the body, not directly controlled by the nervous system.

Correct Answer: B

Rationale: The primary function of the digestive system is to break down food into smaller molecules and absorb nutrients such as vitamins, minerals, carbohydrates, proteins, and fats. These nutrients are then utilized by the body for energy, growth, and repair. The digestive system plays a crucial role in the process of extracting essential components from food and distributing them to the body's cells through the bloodstream. Choices A, C, and D are incorrect because transporting oxygen, producing hormones, and transporting blood are functions associated with other body systems like the respiratory system, endocrine system, and circulatory system, respectively, not the digestive system.

Correct Answer: B

Rationale: The pharynx is indeed a structure located in the upper respiratory tract. It acts as a common passageway for both air heading to the lungs and food traveling to the esophagus, making it a vital structure for breathing and swallowing functions. The larynx, trachea, and esophagus are also part of the respiratory and digestive systems but are not specifically located in the upper respiratory tract. The larynx is situated below the pharynx, while the trachea is found below the larynx, and the esophagus is part of the digestive system, not the respiratory tract.

Correct Answer: A

Rationale: The correct answer is A: "To transport oxygen and nutrients." The primary function of the cardiovascular system is to transport oxygen, nutrients, and hormones to cells throughout the body and remove waste products. This system plays a crucial role in maintaining homeostasis by delivering essential substances to tissues and organs while eliminating metabolic waste. Choices B, C, and D are incorrect because although the cardiovascular system indirectly helps in removing waste products through circulation, its primary function is focused on transporting essential substances and not on regulating body temperature or fighting infections.