What is the function of white blood cells?

Correct Answer: B

Rationale: White blood cells are a vital part of the immune system. Their primary function is to fight infections by attacking bacteria, viruses, and other pathogens that enter the body. They play a crucial role in protecting the body against illnesses and maintaining overall health. Choice A is incorrect because the role of carrying oxygen to cells is primarily performed by red blood cells. Choice C is incorrect as the transportation of nutrients is mainly carried out by the bloodstream and specialized cells. Choice D is incorrect as the process of clotting blood is primarily mediated by platelets.

Correct Answer: C

Rationale: Mitochondria are commonly referred to as the powerhouses of the cell as they are primarily responsible for generating energy through cellular respiration. This process involves converting nutrients into adenosine triphosphate (ATP), which is the main energy currency of the cell. The nucleus is responsible for storing the cell's genetic material, the ribosome is involved in protein synthesis, and the Golgi apparatus is responsible for packaging and distributing molecules produced by the cell; therefore, they are not directly involved in energy generation.

Correct Answer: B

Rationale: The parietal lobe of the brain is responsible for processing sensory information such as touch, temperature, and pain. It integrates sensory information from various parts of the body, allowing an individual to perceive and respond to different stimuli. Functions like spatial awareness and perception of the body's position in space are also associated with the parietal lobe. The frontal lobe is responsible for functions like decision-making and personality. The occipital lobe is primarily involved in visual processing, and the temporal lobe plays a role in memory and auditory processing.

Correct Answer: B

Rationale: The correct answer is B: Pivot joint. A pivot joint, like the one found in the neck, allows for rotational movement, enabling the head to turn from side to side. Hinge joints (Choice A) allow movement in one plane like a door hinge and are not found in the neck. Ball and socket joints (Choice C) allow for a wide range of motion in multiple directions and are typically found in the hip and shoulder. Saddle joints (Choice D) allow for movement back and forth and side to side, like the thumb joint, but are not found in the neck.

Correct Answer: A

Rationale: The hippocampus is the correct answer. It plays a crucial role in memory formation, particularly in the creation of new memories and their association with learning and emotions. Damage to the hippocampus can result in memory impairments, highlighting its significance in cognitive functions. The amygdala (Choice B) is involved in the processing of emotions, while the cerebellum (Choice C) is primarily associated with motor control and coordination. The medulla oblongata (Choice D) is responsible for vital autonomic functions like breathing and heart rate regulation, not memory formation.

Correct Answer: C

Rationale: The correct answer is C: Pancreas. The pancreas is responsible for producing insulin, a hormone that regulates blood glucose levels by facilitating the uptake of glucose into cells. Insulin is crucial for maintaining proper blood sugar levels and is produced by specialized cells within the pancreas known as beta cells. Choices A, B, and D are incorrect because the thyroid gland, pituitary gland, and adrenal gland do not produce insulin. The thyroid gland produces hormones that regulate metabolism, the pituitary gland releases various hormones that control other glands, and the adrenal gland produces hormones like cortisol and adrenaline.

Correct Answer: B

Rationale: Adrenaline, also known as epinephrine, is the correct hormone produced by the adrenal medulla. It plays a crucial role in the body's fight-or-flight response, increasing heart rate, dilating airways, and mobilizing energy stores to prepare the body for perceived threats. Insulin (Choice A) is produced by the pancreas and regulates blood sugar levels, not by the adrenal medulla. Cortisol (Choice C) is produced by the adrenal cortex and is involved in regulating metabolism, immune response, and stress. Melatonin (Choice D) is produced by the pineal gland and regulates the sleep-wake cycle.

Correct Answer: B

Rationale: Arteries are blood vessels that carry oxygenated blood away from the heart to the rest of the body. They have thick, muscular walls to withstand the high pressure generated by the heart's contractions, ensuring efficient transport of blood throughout the body. Veins, on the other hand, carry deoxygenated blood back to the heart, while capillaries facilitate the exchange of nutrients, oxygen, and waste products between the blood and tissues. Nerves are not involved in the transport of blood.

Correct Answer: B

Rationale: The pituitary gland, often referred to as the 'master gland,' is the correct answer. It is responsible for regulating the release of hormones from other endocrine glands in the body. The pituitary gland controls various bodily functions and plays a crucial role in maintaining hormonal balance, making it a central and vital component of the endocrine system. The other options, such as the thyroid gland (A), adrenal gland (C), and pineal gland (D), have important functions in the endocrine system but are not specifically known as the 'master gland.'