Practice TEAS Science Test

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: To fight infection. White blood cells are a vital part of the immune system and are responsible for identifying and destroying pathogens like bacteria and viruses. They play a crucial role in defending the body against infections. A: White blood cells do not transport oxygen. That is the role of red blood cells. C: Red blood cells, not white blood cells, carry oxygen throughout the body. D: While white blood cells can produce antibodies as part of the immune response, their primary function is to directly combat infections.

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: A

Rationale: The correct answer is A: Mediastinum. The mediastinum is the space between the lungs that contains vital structures such as the heart, major blood vessels, esophagus, and trachea. It separates the lungs into right and left compartments. The pericardial cavity (B) is the space that surrounds the heart within the mediastinum. The pleural cavity (C) is the space between the lungs and the chest wall, not between the lungs themselves. Thoracic space (D) is a vague term and does not specifically refer to the space between the lungs.

Correct Answer: D

Rationale: The correct answer is D because the Vas Deferens connects each testis to the urethra, allowing sperm to travel from the testes to the urethra during ejaculation. This tube plays a crucial role in the male reproductive system by transporting sperm for ejaculation. A is incorrect because the production of fluid to increase sperm mobility is carried out by the seminal vesicles and prostate gland. B is incorrect because the site where the egg matures is the fallopian tubes in females. C is incorrect because controlling urine flow is the function of the urethra and muscles in the bladder, not the Vas Deferens.