Practice TEAS Science Test

Correct Answer: B

Rationale: The correct answer is B: To filter waste from the blood. The lymphatic system includes lymph nodes and vessels that help filter out waste, toxins, and pathogens from the blood. Lymphocytes in the lymph nodes also play a key role in immune responses. The other choices (A, C, D) are incorrect because the lymphatic system is not responsible for transporting oxygen (A), producing red blood cells (C), or regulating body temperature (D).

Correct Answer: B

Rationale: The correct answer is B: Alveoli. Alveoli are tiny air sacs in the lungs where gas exchange occurs. Oxygen from the air we breathe passes into the blood vessels surrounding the alveoli, while carbon dioxide from the blood moves into the alveoli to be exhaled. The other choices are incorrect because: A: Trachea is the windpipe that carries air to and from the lungs, but gas exchange does not occur there. C: Bronchioles are small air passages that branch off the bronchi, leading air to the alveoli, but they are not the site of gas exchange. D: Diaphragm is a muscle that helps with breathing by expanding and contracting the chest cavity, but it is not directly involved in gas exchange.

Correct Answer: B

Rationale: The correct answer is B: Jejunum. The jejunum is the primary site of absorption in the small intestine due to its extensive surface area, presence of villi and microvilli that increase absorption capacity, and higher blood supply compared to other regions. It is where most nutrients such as carbohydrates, proteins, and fats are absorbed. The duodenum (A) is mainly responsible for initial digestion, the ileum (C) absorbs bile salts, vitamin B12, and some nutrients, and the cecum (D) is part of the large intestine and is not involved in nutrient absorption.

Correct Answer: D

Rationale: Platelets play a crucial role in clotting blood. When a blood vessel is damaged, platelets rush to the site to form a plug, preventing excessive bleeding. This process, known as hemostasis, involves platelets adhering to the damaged vessel wall, releasing chemicals to attract more platelets, and forming a clot to stop bleeding. Platelets do not transport oxygen (choice A), fight infection (choice B), or produce antibodies (choice C). Thus, the correct answer is D - Clot blood.

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.