Practice TEAS Science Test

Correct Answer: A

Rationale: Insulin is the correct answer as it helps regulate blood sugar levels by facilitating the uptake of glucose into cells. Adrenaline, cortisol, and melatonin do not directly regulate blood sugar levels like insulin does. Adrenaline primarily affects the fight-or-flight response, cortisol is involved in stress response and metabolism, and melatonin regulates sleep-wake cycles. Insulin's role in blood sugar regulation is crucial for maintaining proper glucose levels in the body.

Correct Answer: C

Rationale: The correct answer is C: Large intestine. The large intestine is responsible for absorbing water and forming feces as it reabsorbs water from the indigestible food particles that pass through it, leading to the formation of solid waste (feces). The stomach (A) primarily breaks down food with gastric juices. The small intestine (B) is where most nutrient absorption occurs, not water absorption for feces formation. The esophagus (D) is a muscular tube that carries food from the mouth to the stomach, with no role in water absorption or feces formation.

Correct Answer: B

Rationale: The correct answer is B: Jejunum. The jejunum is the primary site of absorption in the small intestine due to its extensive surface area, presence of villi and microvilli that increase absorption capacity, and higher blood supply compared to other regions. It is where most nutrients such as carbohydrates, proteins, and fats are absorbed. The duodenum (A) is mainly responsible for initial digestion, the ileum (C) absorbs bile salts, vitamin B12, and some nutrients, and the cecum (D) is part of the large intestine and is not involved in nutrient absorption.

Correct Answer: D

Rationale: The correct answer is D: Sympathetic nervous system. This system is responsible for activating the 'fight or flight' response in situations of stress or danger. It triggers physiological changes such as increased heart rate, dilation of pupils, and release of adrenaline. The central nervous system (A) includes the brain and spinal cord but doesn't directly control this response. The peripheral nervous system (B) includes nerves outside the brain and spinal cord but doesn't specifically regulate 'fight or flight'. The autonomic nervous system (C) includes both sympathetic and parasympathetic divisions, with the sympathetic division being the one involved in the 'fight or flight' response.

Correct Answer: B

Rationale: The correct answer is B: To filter waste from the blood. The kidneys are responsible for filtering waste products and excess fluids from the bloodstream to form urine. This process helps maintain the body's overall balance of fluids and electrolytes. Regulating body temperature is primarily controlled by the skin and sweat glands, not the kidneys (choice A). While the kidneys do produce hormones like erythropoietin and renin, their primary function is waste filtration, not hormone production (choice C). Transporting oxygen is primarily the role of the respiratory and circulatory systems, not the kidneys (choice D).