Practice TEAS Science Test

Correct Answer: B

Rationale: The correct answer is B: Protein. Proteins are macromolecules composed of amino acids, which always contain nitrogen in their structure. Amino acids have an amine group (-NH2), which is where the nitrogen is found. Fatty acids (choice A) do not contain nitrogen in their structure. Lipids (choice C) and carbohydrates (choice D) also do not contain nitrogen in their basic structure. Therefore, protein is the only macromolecule among the choices that will always contain nitrogen.

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.

Correct Answer: D

Rationale: The correct answer is D: All of the above. The large intestine plays a crucial role in absorbing water to form solid waste (A). It also houses beneficial bacteria that produce vitamin K, essential for blood clotting and bone health (B). Additionally, the large intestine is involved in the absorption of some vitamin B compounds produced by gut bacteria (C). Thus, all the functions listed (A, B, C) are carried out by the large intestine. Other choices are incorrect because they do not encompass all the functions performed by the large intestine.

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: B

Rationale: The correct answer is B: Lymph nodes. Lymph nodes are responsible for filtering lymph, which carries waste products and pathogens, supporting the immune system by trapping and destroying harmful substances. Lymph nodes contain immune cells that help fight infections. The other choices are incorrect because: A: Kidneys filter blood and regulate fluid balance. C: Pancreas produces digestive enzymes and insulin. D: Liver detoxifies harmful substances and processes nutrients.