Practice TEAS Science Test

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: 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).

Correct Answer: B

Rationale: The correct answer is B: 12 NADPH and 18 ATP. In the Calvin cycle of photosynthesis, each molecule of CO2 requires 2 NADPH and 3 ATP for reduction to glucose. Therefore, to reduce 6 molecules of CO2, you would need 6 x 2 = 12 NADPH and 6 x 3 = 18 ATP. This is why choice B is the correct answer. Choices A, C, and D have incorrect combinations of NADPH and ATP that do not match the stoichiometry of the Calvin cycle for the reduction of CO2 to glucose.

Correct Answer: C

Rationale: Natural Killer Cells produce Perforin to create pores in the target cell membrane, leading to target cell rupture. Perforin forms channels in the cell membrane, allowing for the entry of granzymes that induce apoptosis in the target cell. Interferon is produced by infected cells to inhibit viral replication. Apoptosis is a programmed cell death process. Antibodies are produced by B cells in response to antigens but are not involved in the direct lysis of target cells by Natural Killer Cells.