TEAS Practice Test Science

Correct Answer: B

Rationale: The correct answer is B: Liver. The liver produces bile, a greenish-yellow fluid that aids in digestion by breaking down fats. The pancreas (choice A) produces digestive enzymes, not bile. The gallbladder (choice C) stores and concentrates bile produced by the liver, but it does not produce bile itself. The stomach (choice D) produces gastric juices to break down food, but it does not produce bile. Therefore, the liver is the organ responsible for producing bile to aid in digestion.

Correct Answer: B

Rationale: The correct answer is B: Dendrite. Dendrites are the part of the neuron that receives signals from other neurons, allowing for communication between neurons. They contain receptors that bind to neurotransmitters released by neighboring neurons. The axon (A) is responsible for transmitting signals away from the cell body. The synapse (C) is the junction between two neurons where neurotransmitters are released. The myelin sheath (D) is a protective covering that insulates the axon and speeds up signal transmission but does not receive signals from other neurons.

Correct Answer: C

Rationale: The correct answer is C: Thymus. The thymus is responsible for maturing T cells, a type of white blood cell crucial for immune responses. The thymus is where immature T cells develop into functional T cells through a process called thymic education. The other choices are incorrect because the hypothalamus (A) is involved in regulating hormones, the pineal gland (B) regulates sleep-wake cycles, and the thyroid (D) produces hormones that regulate metabolism. These structures do not have a direct role in maturing T cells.

Correct Answer: B

Rationale: The correct answer is B: Nephron. The nephron is the basic structural and functional unit of the kidney because it is responsible for filtering blood, regulating fluid balance, and producing urine. It consists of the glomerulus, tubules, and collecting ducts. The other choices, A: Neuron, C: Glomerulus, and D: Axon, are not correct as they do not perform the specific functions related to kidney physiology. Neurons are nerve cells, glomerulus is a part of the nephron, and axon is a part of a neuron.

Correct Answer: A

Rationale: The correct answer is A: Left atrium. The left atrium receives oxygenated blood from the lungs via the pulmonary veins. This oxygenated blood is then pumped into the left ventricle and circulated to the rest of the body. The right atrium receives deoxygenated blood from the body via the vena cava. Choices B, C, and D are incorrect because the right atrium receives deoxygenated blood from the body, the left ventricle pumps oxygenated blood to the body, and the right ventricle pumps deoxygenated blood to the lungs for oxygenation, respectively.