Practice TEAS Science Test

Correct Answer: B

Rationale: Iron is the correct answer because it is an essential component of hemoglobin, the protein in red blood cells responsible for transporting oxygen throughout the body. Without iron, the body cannot produce enough hemoglobin, leading to anemia. Calcium, potassium, and sodium do not play a direct role in hemoglobin synthesis. Calcium is important for bone health, potassium is crucial for nerve and muscle function, and sodium helps regulate fluid balance. Iron is the only element among the choices that is directly involved in hemoglobin formation.

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: C

Rationale: The correct answer is C: Pyruvic acid. In glycolysis, glucose is broken down into pyruvic acid. This process involves a series of enzymatic reactions that result in the production of pyruvic acid, which is a crucial intermediate in cellular respiration. Pyruvic acid can then enter the citric acid cycle to further extract energy in the form of ATP. Rationale for other choices: A: ATP is produced during glycolysis, but it is not the end product. B: NADPH is not the end product of glucose breakdown in glycolysis; it is a reducing agent used in various metabolic pathways. D: Oxygen is not directly produced as a result of glucose breakdown in glycolysis; oxygen is utilized in later stages of cellular respiration.

Correct Answer: B

Rationale: The correct answer is B: To fight infection. White blood cells are a vital part of the immune system and are responsible for identifying and destroying pathogens like bacteria and viruses. They play a crucial role in defending the body against infections. A: White blood cells do not transport oxygen. That is the role of red blood cells. C: Red blood cells, not white blood cells, carry oxygen throughout the body. D: While white blood cells can produce antibodies as part of the immune response, their primary function is to directly combat infections.

Correct Answer: B

Rationale: The correct answer is B: Medulla oblongata. The medulla oblongata, located in the brainstem, controls essential functions like breathing and heart rate. It contains centers that regulate these automatic processes. The cerebrum (A) is responsible for higher brain functions, not controlling basic physiological functions. The thalamus (C) serves as a relay station for sensory information, not for regulating breathing and heart rate. The cerebellum (D) plays a role in coordination and movement, not in controlling vital functions like breathing and heart rate.