ATI TEAS Practice Science Test

Correct Answer: C

Rationale: The correct answer is C: Chromosome. A chromosome is a rod-shaped structure formed when a single DNA molecule and its associated proteins coil tightly before cell division. This coiling helps to compact the DNA and ensure it is evenly distributed to daughter cells during cell division. Centromere (A) is a specific region of a chromosome where sister chromatids are joined. Chromatid (B) refers to one of the two identical copies of a chromosome that are joined at the centromere. Gene (D) is a segment of DNA that carries the genetic information for a specific trait. Therefore, the correct answer is chromosome as it specifically describes the rod-shaped structure formed during cell division due to the coiling of DNA and proteins.

Correct Answer: A

Rationale: The correct answer is A: ATP. ATP (adenosine triphosphate) is required to drive the sliding filament process during muscle contraction by providing energy for the myosin heads to bind to actin and generate movement. ATP is directly involved in the process of cross-bridge formation and power stroke. Hormones (B) do not directly drive muscle contraction. Potassium (C) is involved in muscle cell excitability but not in the sliding filament process. Water (D) is not directly involved in muscle contraction.

Correct Answer: C

Rationale: To calculate the mass of the atom, we add the number of protons and neutrons since electrons have negligible mass. In this case, 17 protons + 20 neutrons = 37. Therefore, the correct answer is C. Choice A is incorrect because it only considers the number of protons. Choice B is incorrect because it only considers the number of neutrons. Choice D is incorrect because it does not take into account the total number of protons and neutrons in the atom.

Correct Answer: C

Rationale: The correct order is C: Thrombocytes, erythrocytes, and leukocytes. Thrombocytes (platelets) are the smallest, followed by erythrocytes (red blood cells), then leukocytes (white blood cells). This order is based on the size of these blood cell types, with thrombocytes being the smallest and leukocytes being the largest. Thrombocytes play a crucial role in blood clotting, erythrocytes are responsible for oxygen transport, and leukocytes are essential for immune function. Incorrect choices: A: Incorrect order; leukocytes are the largest, not the smallest. B: Incorrect order; thrombocytes are the smallest, not the largest. D: Incorrect order; leukocytes are larger than erythrocytes, so the order is incorrect.

Correct Answer: D

Rationale: The impaired posterior pituitary gland leads to decreased production of antidiuretic hormone (ADH), resulting in the inability to concentrate urine. This causes the patient to excrete large volumes of dilute urine. Thirst (choice A) is a symptom of diabetes insipidus, a condition related to ADH deficiency. Tiredness (choice B) and weight gain (choice C) are not directly associated with impaired posterior pituitary function. Thus, choice D, concentrated urine, is the correct symptom related to kidney function in this scenario.