Practice TEAS Science Test

Correct Answer: C

Rationale: The correct answer is C: Lymphatic System. The lymphatic system drains clear fluid called lymph throughout the body to protect it from infection by filtering out harmful pathogens and waste products. The lymphatic system plays a crucial role in the body's immune response. A: Pulmonary Loop is related to the circulation of blood between the heart and lungs for oxygenation, not draining clear fluid for immune protection. B: Systemic Loop pertains to the circulation of oxygenated blood from the heart to the body's tissues and back, not draining clear fluid for immune protection. D: Immune System is responsible for defending the body against infections and diseases but does not specifically focus on draining clear fluid throughout the body.

Correct Answer: B

Rationale: The correct answer is B: ATP energy. Cellular respiration is the process by which cells convert glucose into ATP, the primary energy source for cellular activities. During cellular respiration, glucose is broken down in the presence of oxygen to produce ATP through a series of metabolic reactions. Oxygen (choice A) is required for cellular respiration but is not an end product. Carbon dioxide (choice C) is a byproduct of cellular respiration, not an end product. Water (choice D) is not directly produced as an end product of cellular respiration. Thus, choice B is the correct answer as ATP energy is the main end product generated from cellular respiration.

Correct Answer: B

Rationale: The correct answer is B: Vitamin D. When skin is exposed to sunlight, it triggers the production of Vitamin D in the body. Sunlight activates a form of cholesterol in the skin, which then converts to Vitamin D through a series of chemical reactions. Vitamin A (Choice A) is not produced by sunlight but is found in foods like carrots. Vitamin K (Choice C) is involved in blood clotting and bone health but is not produced by sunlight. Vitamin E (Choice D) is an antioxidant found in foods like nuts and seeds, not produced through sun exposure.

Correct Answer: B

Rationale: The correct answer is B: Medulla oblongata. This part of the brain is located in the brainstem and is responsible for controlling vital involuntary functions like breathing, heart rate, and blood pressure. It contains nuclei that regulate these activities and plays a crucial role in maintaining homeostasis. The cerebellum (A) is involved in coordinating movement and balance, the cerebrum (C) is responsible for higher brain functions like thinking and decision-making, and the thalamus (D) acts as a relay center for sensory information. However, they are not directly involved in controlling involuntary actions like breathing and heart rate.

Correct Answer: A

Rationale: The correct answer is A: Ectoderm. During embryonic development, the nervous system originates from the ectoderm layer. The neural plate forms from the ectoderm, which further develops into the neural tube and neural crest cells, giving rise to the brain, spinal cord, and peripheral nervous system. The other choices, B: Endoderm, C: Gastroderm, and D: Mesoderm, do not give rise to the nervous system. Endoderm forms the innermost layer of organs like the gut, Gastroderm is not a recognized germ layer, and Mesoderm gives rise to structures like muscles, bones, and connective tissues, not the nervous system.