ATI TEAS 7 Science

Correct Answer: C

Rationale: The correct answer is C: GABA. GABA is an inhibitory neurotransmitter that slows down neuron activity by binding to GABA receptors, leading to hyperpolarization of the neuron and reducing the likelihood of firing an action potential. This process helps to prevent overexcitation in the nervous system. A: Acetylcholine is primarily an excitatory neurotransmitter involved in muscle control and cognitive function. B: Dopamine plays a role in reward-motivated behavior and movement, but it is not primarily responsible for slowing down neuron activity. D: Serotonin is involved in regulating mood, appetite, and sleep, but it does not directly slow down neuron activity to prevent overexcitation.

Correct Answer: B

Rationale: The primary function of red blood cells is to transport oxygen. They contain hemoglobin, which binds to oxygen in the lungs and delivers it to tissues throughout the body. This process is essential for cellular respiration and energy production. Choice A is incorrect because while red blood cells do transport nutrients, their main role is oxygen transport. Choice C is incorrect because fighting infection is primarily the role of white blood cells. Choice D is incorrect as red blood cells do not produce antibodies; that is the function of specialized white blood cells called B cells.

Correct Answer: B

Rationale: The correct answer is B: Liver. The liver is responsible for detoxifying chemicals and metabolizing drugs due to its enzymes that break down substances. It also helps in excreting waste products. The kidneys (A) filter blood and regulate fluid balance. The heart (C) pumps blood throughout the body. The pancreas (D) produces digestive enzymes and insulin. Thus, the liver is the primary organ involved in detoxification and drug metabolism.

Correct Answer: A

Rationale: The correct answer is A: Solid. Solids have both a definite volume and a definite shape because the particles are tightly packed and vibrate in fixed positions. This leads to a rigid structure and minimal movement, maintaining the shape and volume. In contrast, liquids (B) have a definite volume but take the shape of their container, gases (C) have neither a definite shape nor volume as they expand to fill the container, and plasmas (D) have no definite shape or volume due to their high energy state.

Correct Answer: A

Rationale: The correct answer is A: Hydrogen bonding. Water molecules exhibit hydrogen bonding, where the partially positive hydrogen of one water molecule is attracted to the partially negative oxygen of another water molecule. This strong intermolecular force leads to the cohesive forces that create high surface tension in water. B: London dispersion forces are weaker and do not contribute significantly to water's high surface tension. C: Ionic bonding involves the transfer of electrons between atoms, not relevant to water's surface tension. D: Metallic bonding occurs in metals and is not related to the surface tension of water.