Practice Science TEAS Test

Correct Answer: D

Rationale: Step-by-step rationale: 1. A: The atrioventricular valves lie between the atria and the ventricles - This is true for both the tricuspid valve (right side) and the mitral valve (left side). 2. B: The pulmonary semilunar valve lies between the right ventricle and the pulmonary trunk - This is accurate, as the pulmonary semilunar valve separates the right ventricle from the pulmonary artery. 3. C: The atrioventricular valves prevent backflow into the atria when the ventricles contract - This is true as the AV valves close to prevent backflow during ventricular contraction. 4. Therefore, the correct answer is D, as all the statements are correct and accurately describe heart valve anatomy and function.

Correct Answer: B

Rationale: Cytokinesis refers to the division of the cytoplasm during cell division, specifically following the separation of chromosomes. This process results in two daughter cells being formed. The correct answer is B because it accurately describes the final step in cell division where the cytoplasm is divided to complete the formation of two separate daughter cells. Choices A, C, and D are incorrect as they do not specifically pertain to the process of cytokinesis. Choice A refers to the division of the nucleus, which is known as mitosis. Choice C refers to the separation of chromosomes, which is part of the earlier stages of cell division. Choice D refers to the formation of spindle fibers, which are involved in chromosome movement during mitosis but not directly related to cytokinesis.

Correct Answer: B

Rationale: The correct answer is B: Luteinizing Hormone. The pituitary gland secretes luteinizing hormone, which plays a crucial role in the reproductive system by stimulating ovulation in females and testosterone production in males. Estrogen, progesterone, and testosterone are not directly released by the pituitary gland but are instead produced by other glands such as the ovaries, testes, and adrenal glands. Therefore, B is the correct choice as it is the hormone directly released by the pituitary gland.

Correct Answer: B

Rationale: The correct answer is B: Hypothalamus. The hypothalamus regulates body temperature, hunger, and thirst through its control of the autonomic nervous system and hormonal systems. It plays a crucial role in maintaining homeostasis. The cerebellum (A) is responsible for coordination and balance, the thalamus (C) acts as a relay station for sensory information, and the medulla oblongata (D) regulates vital functions such as breathing and heart rate, but not body temperature, hunger, or thirst.

Correct Answer: C

Rationale: The correct answer is C: Spleen. The spleen filters pathogens from the blood through its white pulp, which contains immune cells that detect and destroy harmful microorganisms. The spleen also removes old or damaged red blood cells. A: Lymph nodes filter lymph, not blood. B: Kidneys filter waste from the blood but not pathogens. D: Pancreas is primarily involved in digestion and hormone regulation, not blood filtration.