ATI TEAS Practice Science Test

Correct Answer: B

Rationale: The correct answer is B because endocrine glands release hormones directly into the bloodstream. Therefore, an extensive network of blood vessels is necessary to facilitate the direct release of hormones into the blood for systemic circulation. The other choices are incorrect because: A: Filtering waste from the blood is the function of the kidneys, not the endocrine glands. C: Blood does not "empty" into the endocrine system; rather, hormones are released into the bloodstream. D: Endocrine glands do not filter waste; instead, they produce and release hormones into the blood for various physiological functions.

Correct Answer: A

Rationale: The correct answer is A: Diffusion. Gas exchange in the respiratory system occurs through diffusion, where oxygen moves from the alveoli in the lungs to the blood and carbon dioxide moves from the blood to the alveoli. This process is driven by a concentration gradient, allowing for the exchange of gases between the air and blood. Exhalation (choice B) is the process of expelling air from the lungs, not the mechanism of gas exchange. Inspiration (choice C) is the process of inhaling air into the lungs, but it is not directly involved in gas exchange. Ventilation (choice D) refers to the movement of air into and out of the lungs and is necessary for gas exchange to occur but is not the actual mechanism of gas exchange itself.

Correct Answer: C

Rationale: The correct answer is C: Flexor. Flexor muscles are responsible for bending a joint by decreasing the angle between the bones they act upon. They contract to bring two body parts closer together. Cardiac muscles (A) are found in the heart and control its pumping action. Extension (B) refers to the straightening of a joint, not bending. Smooth muscles (D) are found in various organs and are not directly involved in joint movement. Therefore, the flexor muscle (C) is the correct choice for causing a joint to bend.

Correct Answer: B

Rationale: To convert grams to kilograms, we divide by 1000 since there are 1000 grams in a kilogram. Therefore, 1800 grams divided by 1000 equals 1.8 kilograms. Choice B is correct. Choice A is incorrect because 0.18 is the result of dividing by 10, not 1000. Choice C is incorrect as it is 10 times the correct answer. Choice D is incorrect as it is 100 times the correct answer.

Correct Answer: B

Rationale: The correct answer is B because rugae increase the surface area of the stomach, allowing for better absorption of nutrients and more efficient digestion. This increased surface area facilitates the breakdown of food particles and enhances the absorption of nutrients into the bloodstream. The other choices are incorrect because rugae do not directly impact the output of gastric juices (A), permeability of stomach walls (C), or types of nutrients that can diffuse (D).