TEAS Practice Test Science

Correct Answer: B

Rationale: The pancreas produces insulin to lower blood sugar levels and glucagon to raise them. Insulin helps cells take in glucose for energy or storage. Glucagon signals the liver to release stored glucose. Storing glucose (option C) is not the primary function of the pancreas. Adrenaline (option D) is produced by the adrenal glands, not the pancreas.

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: Mitochondria. Mitochondria are known as the powerhouse of the cell because they are responsible for producing ATP through cellular respiration. This process involves the breakdown of glucose to generate energy in the form of ATP. Ribosomes (A) are responsible for protein synthesis, the nucleus (B) houses the cell's genetic material, and the endoplasmic reticulum (D) is involved in protein synthesis and lipid metabolism, but not ATP production. Mitochondria's unique structure and enzymes make them the primary site for ATP production in the cell.

Correct Answer: D

Rationale: The correct answer is D: Vacuole. Vacuoles are responsible for storing food, water, and other materials in the cell. They help maintain turgor pressure and regulate the cell's internal environment. Centrioles are involved in cell division, lysosomes contain digestive enzymes, and ribosomes are responsible for protein synthesis. So, A, B, and C are incorrect choices for food and water storage in the cell.

Correct Answer: B

Rationale: The correct answer is B: To exchange gases. The main function of the respiratory system is to facilitate the exchange of oxygen and carbon dioxide between the body and the external environment. This process occurs in the lungs through breathing, where oxygen is taken in and carbon dioxide is expelled. Absorbing nutrients (A) is the function of the digestive system, transporting oxygen (C) is part of the circulatory system's role, and regulating blood pressure (D) is primarily controlled by the cardiovascular system.