Practice Science TEAS Test

Correct Answer: B

Rationale: The correct answer is B: Vein. Veins carry blood back to the heart, while arteries carry blood away from the heart. Capillaries are tiny blood vessels where exchange of nutrients and waste occurs. Lymphatic vessels carry lymph fluid, not blood. Veins have valves to prevent backflow and low pressure due to distance from the heart.

Correct Answer: B

Rationale: The correct answer is B: Glycolysis. Glycolysis is the process where glucose is broken down into pyruvic acid through a series of enzymatic reactions in the cytoplasm. This process involves multiple steps including phosphorylation, isomerization, cleavage, and oxidation. Glycogenesis (choice A) is the synthesis of glycogen from glucose, not the breakdown. Glycogenolysis (choice C) is the breakdown of glycogen into glucose, not the conversion of glucose to pyruvic acid. Gluconeogenesis (choice D) is the synthesis of glucose from non-carbohydrate precursors, not the conversion of glucose to pyruvic acid.

Correct Answer: B

Rationale: The correct answer is B: Glucose. Glucose is a monosaccharide because it is a single sugar molecule, the simplest form of carbohydrates. Starch (A) is a polysaccharide made up of multiple glucose units. Cellulose (C) is also a polysaccharide, not a monosaccharide. Sucrose (D) is a disaccharide composed of glucose and fructose molecules. So, only glucose (B) fits the definition of a monosaccharide in this question.

Correct Answer: B

Rationale: The correct answer is B: Pineal gland. The pineal gland secretes the hormone melatonin, which plays a crucial role in regulating the body's circadian rhythm. Melatonin helps control the sleep-wake cycle, making it responsible for maintaining the body's internal clock. The other choices are incorrect because the thyroid gland regulates metabolism (A), the pancreas regulates blood sugar levels (C), and the hypothalamus controls various bodily functions but is not directly responsible for maintaining the circadian rhythm (D).

Correct Answer: B

Rationale: The correct answer is B: Retina. The retina is a layer of light-sensitive cells located at the back of the eye that detects light and converts it into signals for the brain through the optic nerve. The iris (A) controls the amount of light entering the eye, the lens (C) helps to focus light onto the retina, and the pupil (D) regulates the amount of light entering the eye, but they do not convert light into signals for the brain like the retina does.