teas 7 practice test free science - Nurselytic

Correct Answer: A

Rationale: The vas deferens is the correct answer. It is the tube that carries sperm from the testes to the urethra during ejaculation. The vas deferens plays a crucial role in transporting mature sperm for ejaculation. The epididymis is responsible for sperm maturation and storage, not the direct passage of sperm to the urethra. The seminal vesicle produces fluid that combines with sperm to form semen but is not the tube for sperm transport. The urethra serves as the passageway for both urine and semen out of the body but is not the specific tube that transports sperm from the testes to the urethra.

Correct Answer: B

Rationale: Estuaries are coastal areas where freshwater from rivers and streams mixes with saltwater from the ocean. They serve as important habitats for a variety of marine life, including fish, birds, and other wildlife. Estuaries provide shelter, breeding grounds, and food sources for many species, making them crucial for the overall health of marine ecosystems. While estuaries can help filter pollutants to some extent, their primary function is to support and sustain diverse populations of plants and animals. Storing carbon dioxide and generating wind power are not main functions of estuaries.

Correct Answer: C

Rationale: Vaccines primarily function by stimulating the immune system to develop immunological memory to a specific pathogen. When a vaccine is administered, it exposes the immune system to a harmless version of a pathogen or a piece of it. This exposure triggers the immune response, leading to the production of antibodies and memory cells specific to that pathogen.
Choice A is incorrect because vaccines do not create a physical barrier; rather, they prepare the immune system to recognize and fight specific pathogens.
Choice B is incorrect as vaccines do trigger an immune response, but the primary goal is to create memory rather than inflammation.
Choice D is incorrect as vaccines do not directly activate phagocytes; instead, they stimulate the immune system to generate a targeted response against a particular pathogen.

Correct Answer: A

Rationale: The unit of force in the SI system is the Newton (N). It is defined as the amount of force required to accelerate a mass of one kilogram at a rate of one meter per second squared. In the SI system, force is measured in Newtons, not in kilograms, meters, or seconds.
Choice B, Kilogram (kg), is incorrect because kilograms are units of mass, not force.
Choice C, Meter (m), is incorrect because meters are units of length, not force.
Choice D, Second (s), is incorrect because seconds are units of time, not force.

Correct Answer: A

Rationale: The complete combustion of propane (C3H8) results in the production of carbon dioxide (CO2) and water. When a hydrocarbon such as propane undergoes complete combustion, the carbon atoms combine with oxygen to form CO2. This makes choice A, CO2, the correct answer.

Choices B, C, and D are incorrect as CO is carbon monoxide, CH4 is methane, and C is elemental carbon, none of which are the primary product of the complete combustion of propane.