Science TEAS Practice Test

Correct Answer: D

Rationale: The correct answer is D: Veins. Veins have the lowest blood pressure among the structures listed. This is because veins have thinner walls and larger lumens compared to arteries and arterioles, which results in less resistance to blood flow and lower pressure. Venules are small vessels that connect capillaries to veins and have slightly higher pressure than veins. Arteries and arterioles have thicker walls and smaller lumens to withstand the higher pressure of blood ejected by the heart. Therefore, veins have the lowest blood pressure due to their structural characteristics.

Correct Answer: D

Rationale: The correct answer is D because the immune system is responsible for protecting the body from infections by identifying and eliminating harmful pathogens. It helps the body recognize and respond to foreign invaders such as bacteria and viruses. The hypothalamus (Choice A) is not directly involved in immune system function. While the immune system can help remove toxins, its primary role is to combat infections, not filter toxins from the blood (Choice B). Although infections can sometimes trigger the production of more white blood cells, the immune system's primary function is not to stimulate blood cell production (Choice C).

Correct Answer: B

Rationale: The correct answer is B. If an organism is AB, it means they have alleles A and B. In gametes, each gamete carries only one allele. Therefore, gametes with AA are not possible as they lack the B allele. Gametes with AB are possible since they can carry either A or B allele. Gametes with BB are not possible as they lack the A allele. Gametes with AB are possible as they can carry either A or B allele.

Correct Answer: B

Rationale: The correct answer is B: Secondary structure. Secondary structure refers to the local folding patterns of the polypeptide backbone, mainly involving alpha helices and beta sheets. This level of protein structure is determined by hydrogen bonding between amino acids along the backbone. Primary structure (A) is the linear sequence of amino acids, tertiary structure (C) refers to the overall 3D shape of a protein, and quaternary structure (D) involves the arrangement of multiple protein subunits. In this case, the question specifically asks about the folds and coils of the polypeptide backbone, which align with the characteristics of secondary structure.

Correct Answer: D

Rationale: The correct answer is D: Help red blood cells transport oxygen. Hemoglobin is a protein in red blood cells that binds to oxygen in the lungs and releases it in tissues. It does not transport oxygen itself, but it aids red blood cells in carrying oxygen. Choice A is incorrect because hemoglobin carries oxygen, not transports it. Choice B is incorrect because hemoglobin binds to oxygen, not to red blood cells. Choice C is incorrect because hemoglobin primarily transports oxygen, not carbon dioxide.