ATI TEAS 7 Science

Correct Answer: B

Rationale: The primary function of the small intestine is to absorb nutrients from digested food. This process involves breaking down food into smaller molecules that can be absorbed into the bloodstream for energy and growth. The small intestine has villi and microvilli that increase its surface area for efficient nutrient absorption. Choice A is incorrect because the large intestine, not the small intestine, primarily absorbs water. Choice C is incorrect as the large intestine, not the small intestine, stores waste. Choice D is incorrect because while the small intestine does produce some enzymes, its primary role is nutrient absorption.

Correct Answer: C

Rationale: The correct answer is C: Nephron. The nephron is the functional unit of the kidney responsible for filtering blood and reabsorbing essential substances like water, salts, and nutrients back into the body. It consists of various components like the glomerulus, proximal tubule, loop of Henle, and distal tubule, each playing a specific role in the reabsorption process. The renal artery brings blood to the kidney for filtration by the nephron, while the renal vein carries filtered blood away from the kidney. The glomerulus is a part of the nephron responsible for initial filtration of blood. Thus, the nephron is the correct structure for reabsorption, making choices A, B, and D incorrect.

Correct Answer: D

Rationale: The correct answer is D: tRNA. Transfer RNA (tRNA) carries amino acids to ribosomes during protein synthesis. tRNA has an anticodon that pairs with the mRNA codon, ensuring the correct amino acid is added to the growing polypeptide chain. A: DNA carries genetic information but does not directly participate in protein synthesis. B: mRNA carries the genetic information from DNA to the ribosomes but does not carry amino acids. C: rRNA is a structural component of ribosomes and helps in protein synthesis but does not carry amino acids to the ribosomes.

Correct Answer: D

Rationale: Certainly! The correct answer is D because saltatory conduction is faster than normal nerve conduction (A), occurs from one node of Ranvier to the next (B), and only occurs in myelinated neurons (C). This process involves the rapid transmission of action potentials in myelinated axons, where the impulse "jumps" from one node of Ranvier to the next, skipping the myelinated regions in between. This allows for faster conduction speeds compared to continuous conduction in unmyelinated neurons. Therefore, all of the statements in options A, B, and C are accurate descriptions of saltatory conduction, making option D the correct choice.

Correct Answer: D

Rationale: The correct answer is D, Collagen. Collagen is a fibrous protein known for its structural role in connective tissues. It has a triple helix structure, providing strength and support to tissues. Insulin (A) is a hormone, not a fibrous protein. Keratin (B) is a structural protein found in hair and nails. Hemoglobin (C) is a globular protein responsible for oxygen transport in red blood cells. Therefore, collagen is the only fibrous protein among the choices.