Which part of the spinal cord is responsible for transmitting sensory information from the body to the brain?

Correct Answer: A

Rationale: The correct answer is the dorsal root. The dorsal root of the spinal cord contains sensory nerve fibers that transmit sensory information from the body to the brain. This information includes touch, pain, temperature, and proprioception. The ventral root, on the other hand, contains motor nerve fibers responsible for carrying signals from the brain to the muscles and glands, controlling movement and glandular functions. Gray matter, consisting mainly of cell bodies, is involved in processing and integrating sensory and motor information within the spinal cord. White matter is primarily composed of myelinated axons that facilitate communication between different regions of the nervous system, allowing signals to travel efficiently within the spinal cord and between the brain and other parts of the body. Therefore, the dorsal root is specifically associated with transmitting sensory information, making it the correct answer in this context.

Correct Answer: A

Rationale: The correct answer is Growth hormone (GH). GH, produced by the pituitary gland, is responsible for stimulating the growth and development of bones, muscles, and organs. It plays a critical role in regulating growth during childhood and adolescence by promoting cell division, protein synthesis, and tissue growth. Thyroid-stimulating hormone (TSH) functions to stimulate the thyroid gland to produce thyroid hormones, while prolactin is involved in milk production. Follicle-stimulating hormone (FSH) is primarily responsible for reproductive functions like egg development in females and sperm production in males.

Correct Answer: D

Rationale: The Sinoatrial (SA) node is responsible for generating the electrical impulses that regulate the heartbeat. It is often referred to as the heart's natural pacemaker because it initiates the electrical signals that coordinate the heart's contractions. The other options listed (Aorta, Pulmonary veins, Coronary arteries) do not play a direct role in generating the electrical impulses for the heartbeat. The Aorta is a large artery that carries oxygen-rich blood away from the heart, the Pulmonary veins carry oxygen-rich blood from the lungs to the heart, and the Coronary arteries supply blood to the heart muscle itself, but none of them are involved in generating the electrical impulses that regulate the heartbeat.

Correct Answer: C

Rationale: The primary function of the epiglottis in the respiratory system is to prevent food from entering the trachea. During swallowing, the epiglottis covers the opening of the trachea, guiding food down the esophagus to the stomach and preventing it from entering the airway. This mechanism safeguards the respiratory system from foreign objects, ensuring proper air passage and avoiding potential choking hazards. Choices A, B, and D are incorrect: A) Filtration of air is mainly performed by the nasal hairs and the mucous membranes of the respiratory tract. B) Production of mucus is primarily carried out by the mucous glands in the respiratory system to trap particles and humidify the air. D) Oxygen exchange in the alveoli occurs in the lungs and is related to the process of respiration, not the function of the epiglottis.

Correct Answer: B

Rationale: The nucleus is the organelle that contains the genetic material (DNA) of the cell. It acts as the control center of the cell, regulating gene expression and coordinating cellular activities. The cytoplasm is the fluid-filled space within the cell where organelles are suspended, but it does not contain the genetic material. The cell wall is a rigid structure found in plant cells that provides support and protection, but it does not house the DNA. The Golgi apparatus is involved in processing and packaging proteins for secretion, but it does not contain the genetic material of the cell.