TEAS 7 Science Practice Test

Correct Answer: C

Rationale: The correct answer is C: Antibodies. Adaptive immunity involves the body's ability to recognize and remember specific pathogens, such as viruses or bacteria. Antibodies are proteins produced by the immune system in response to these specific pathogens, providing targeted defense. In contrast, choices A and B (inflammation and fever) are examples of innate immunity, which are non-specific responses to pathogens. Choice D, phagocytosis, is a component of both innate and adaptive immunity, involving the engulfment and destruction of pathogens by immune cells. However, antibodies represent a key feature of adaptive immunity by specifically targeting and neutralizing pathogens.

Correct Answer: A

Rationale: The correct answer is A because cytokines are signaling molecules that facilitate communication between immune cells to regulate the immune response. They help coordinate the immune system's actions by promoting inflammation, activating immune cells, and regulating immune responses. Choice B is incorrect because cytokines do not inhibit blood clotting but may actually play a role in promoting clotting during inflammation. Choice C is incorrect because cytokines do not bind to specific pathogens to increase their mass; rather, they regulate immune responses against pathogens. Choice D is incorrect because cytokines do not transport pathogens trapped in mucus to the stomach for destruction; this function is typically carried out by other components of the immune system such as phagocytes.

Correct Answer: A

Rationale: The correct answer is A: capillaries. Capillaries are tiny blood vessels where the exchange of oxygen and nutrients occurs between the blood and tissues through diffusion. Capillaries have thin walls to facilitate the exchange process efficiently. Veins carry blood back to the heart, ventricles are chambers of the heart, and arteries carry blood away from the heart. Thus, they are not sites for oxygen exchange between blood and tissues.

Correct Answer: D

Rationale: The correct answer is D: high polarity. Water molecules are polar, with a slightly positive end (hydrogen) and a slightly negative end (oxygen). This polarity allows water to form hydrogen bonds with other polar molecules, like ionic salt compounds, facilitating their dissolution. Adhesion (A) is the ability of water to stick to other substances, cohesion (B) is the ability of water molecules to stick to each other, and high specific heat (C) is the ability of water to resist temperature changes. These properties are not directly related to water's ability to dissolve ionic salt compounds.

Correct Answer: A

Rationale: The correct answer is A: mRNA. mRNA (messenger RNA) contains the code for making a protein through a process called translation. mRNA is transcribed from DNA in the nucleus and carries the genetic information to the ribosomes where protein synthesis occurs. tRNA (choice B) brings amino acids to the ribosome, rRNA (choice C) is a component of the ribosome, and DNA polymerase (choice D) is involved in DNA replication, not protein synthesis.