Practice TEAS Science Test

Correct Answer: B

Rationale: The correct answer is B: Medulla oblongata. This part of the brain is located in the brainstem and is responsible for controlling vital involuntary functions like breathing, heart rate, and blood pressure. It contains nuclei that regulate these activities and plays a crucial role in maintaining homeostasis. The cerebellum (A) is involved in coordinating movement and balance, the cerebrum (C) is responsible for higher brain functions like thinking and decision-making, and the thalamus (D) acts as a relay center for sensory information. However, they are not directly involved in controlling involuntary actions like breathing and heart rate.

Correct Answer: B

Rationale: The correct answer is B: Lymph nodes. Lymph nodes are responsible for filtering lymph, which carries waste products and pathogens, supporting the immune system by trapping and destroying harmful substances. Lymph nodes contain immune cells that help fight infections. The other choices are incorrect because: A: Kidneys filter blood and regulate fluid balance. C: Pancreas produces digestive enzymes and insulin. D: Liver detoxifies harmful substances and processes nutrients.

Correct Answer: B

Rationale: The correct answer is B: To filter waste from the blood. The kidneys play a crucial role in filtering waste products, excess substances, and toxins from the blood to form urine. This process helps maintain the body's overall balance of fluids and electrolytes. Choices A, C, and D are incorrect as the kidneys do not produce digestive enzymes (A), white blood cells (C), or red blood cells (D). The primary function of the kidneys is to regulate fluid and electrolyte balance, remove waste products, and help control blood pressure.

Correct Answer: D

Rationale: The correct answer is D: Pia mater. Pia mater is the innermost meningeal layer that is a thin membrane containing nerves and blood vessels. It directly covers the brain and spinal cord, supplying nourishment to the underlying cells. Arachnoid mater (A) is the middle meningeal layer that does not contain nerves and blood vessels. Dura mater (B) is the tough outermost layer that does not supply nourishment. Periosteum (C) is a connective tissue covering bones, not the meninges.

Correct Answer: B

Rationale: The correct answer is B (2 ATP molecules produced per FADH2 molecule) in aerobic respiration. FADH2 enters the electron transport chain at a later stage compared to NADH, leading to the production of 2 ATP through oxidative phosphorylation. FADH2 donates electrons to Complex II, bypassing Complex I, resulting in a lower energy yield compared to NADH which donates electrons to Complex I. Choice A (1 ATP) is incorrect as FADH2 produces more ATP than that. Choice C (3 ATP) is incorrect as FADH2 produces 2 ATP, not 3. Choice D (4 ATP) is incorrect as FADH2 produces 2 ATP, not 4.