ATI TEAS Science Test

Correct Answer: A

Rationale: A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. It works by providing an alternate pathway for the reaction to occur, lowering the activation energy needed for the reaction to proceed. As a result, more reactant molecules can overcome this energy barrier and participate in the reaction, leading to a faster overall reaction rate. This explanation contradicts choices B, C, and D as a catalyst does not slow down, reverse, or prevent a reaction; instead, it accelerates the reaction by facilitating a more efficient route for the reaction to take place. Therefore, the correct answer is that a catalyst speeds up the reaction.

Correct Answer: D

Rationale: The correct answer is D: Somatic. The somatic nervous system is responsible for controlling voluntary motor movements. It includes the motor neurons that innervate skeletal muscles and allows us to consciously control our movements. The parasympathetic and sympathetic nervous systems are part of the autonomic nervous system, which controls involuntary functions such as heart rate and digestion. Therefore, choices A, B, and C are incorrect as they are components of the autonomic nervous system and are not primarily responsible for voluntary motor movements.

Correct Answer: B

Rationale: The possible conclusion that can be drawn from every child in a certain family suffering from autism is that autism may be genetic. The fact that every child in the family has autism suggests a strong genetic influence on the condition within this particular family. This does not necessarily mean that autism is solely genetic in all cases, but in this specific family, the pattern of all children being affected points towards a genetic connection. Choice A is incorrect as the information provided does not suggest that autism is lethal. Choice C is incorrect as there is no evidence to support a relationship between autism and traditional nuclear family structures. Choice D is incorrect because a conclusion can be drawn from the given evidence, indicating a potential genetic link within this specific family.

Correct Answer: B

Rationale: The correct answer is B. The process of coagulation, also known as blood clotting, begins instantly after a blood vessel has been damaged. When a blood vessel is injured, the body quickly responds by initiating a cascade of reactions to form a blood clot, which helps to stop bleeding and promote healing. Choices A, C, and D are incorrect because coagulation does not occur just when blood changes from a gel to liquid form, it is not a response of blood drying upon contact with air, and it is not simply the formation of fibrin. The primary trigger for coagulation is vascular injury.

Correct Answer: B

Rationale: The circulatory system is the correct answer as it plays a crucial role in maintaining control of body temperature through a process called thermoregulation. Blood vessels near the skin surface dilate to dissipate heat when the body is too warm and constrict to reduce heat loss when it's too cold. Additionally, the circulatory system helps distribute heat produced from metabolic processes throughout the body to keep a stable internal temperature. The skeletal system provides structural support, the immune system defends against pathogens, and the muscular system is responsible for movement, but they are not primarily involved in regulating body temperature.