Science TEAS Practice Test

Correct Answer: A

Rationale: The correct answer is A: Condensation is the process of changing from a gas to a liquid. This is because condensation occurs when a gas loses heat energy and transitions into a liquid state. The gas molecules slow down and come closer together, forming liquid droplets. Explanation: 1. In condensation, gas molecules lose energy and move closer together. 2. This causes the gas to transition into a liquid state. 3. The process of condensation is commonly observed in everyday situations like when water vapor in the air cools and forms dew on a cold surface. Summary: B: Changing from a liquid to a gas is called evaporation, not condensation. C: Changing from a solid to a liquid is called melting, not condensation. D: Changing from a solid to a gas is called sublimation, not condensation.

Correct Answer: D

Rationale: The correct answer is D because all the statements provide reasonable explanations for the decrease in mortality during childbirth in the 21st century. A: Cesarean sections can be life-saving in cases of complications like prolonged labor or fetal distress. B: Monitoring tools help detect issues early, allowing for timely interventions and prevention of complications. C: Good hand hygiene reduces the risk of infections that could lead to maternal mortality. Therefore, by combining the advancements in cesarean sections, monitoring tools, and infection prevention practices, modern healthcare has significantly reduced maternal mortality rates compared to the 18th century.

Correct Answer: B

Rationale: The correct answer is B: Liver. The liver is primarily responsible for detoxification in the body as it processes and removes toxins, drugs, and other harmful substances from the bloodstream. It metabolizes these toxins into less harmful compounds that can be excreted from the body. The kidney, although important for filtering waste and regulating electrolytes, is not primarily responsible for detoxification. The lung primarily functions in gas exchange, and the heart is responsible for pumping blood throughout the body, not for detoxification. Therefore, the liver is the correct choice for the organ primarily responsible for detoxification.

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: A

Rationale: The correct answer is A: The sinoatrial node. The SA node is known as the heart's natural pacemaker as it initiates electrical impulses that regulate the heart rate. It is located in the right atrium and generates rhythmic electrical signals that stimulate the cardiac muscle to contract. The left ventricle (B), aorta (C), and tricuspid valve (D) do not serve as electrical stimulators of the cardiac muscle. The left ventricle is a chamber that pumps oxygenated blood, the aorta is the largest artery that carries blood away from the heart, and the tricuspid valve controls blood flow between the right atrium and right ventricle.