TEAS 7 Science Practice Test

Correct Answer: D

Rationale: The correct answer is D: insulin production and blood sugar regulation. The liver is not responsible for insulin production; it is produced by the pancreas. The liver does play a role in blood sugar regulation by storing and releasing glucose, but it is not the primary organ for insulin production. The other choices (A, B, C) are functions of the liver: A) nutrient processing involves metabolizing and storing nutrients, B) blood filtration and detoxification involves removing toxins from the blood, and C) cholesterol and lipoprotein production involves synthesizing cholesterol and lipoproteins.

Correct Answer: C

Rationale: The correct answer is C: skin. Skin is the primary physical barrier that the body uses to prevent infection. It acts as a protective barrier, preventing pathogens from entering the body. The outer layer of the skin, known as the epidermis, is made up of tightly packed cells that are difficult for pathogens to penetrate. Additionally, skin produces oils and sweat that contain antimicrobial properties, further protecting against infections. Explanation for why other choices are incorrect: A: Mucus membranes play a role in preventing infections in certain areas like the respiratory and digestive tracts, but they are not the primary physical barrier used by the body. B: Stomach acid is a chemical barrier rather than a physical barrier against infections. D: Urine helps to flush out pathogens from the urinary tract but is not the primary physical barrier used by the body.

Correct Answer: D

Rationale: The correct answer is D because a control group is necessary in experiments to compare results with a group that does not receive the experimental treatment. In this case, if tanks A, B, or C were chosen as the control group, there would be no basis for comparison with a group that did not receive any treatment. Therefore, without a specific control group that does not undergo any experimental manipulation, it is not possible to determine the true impact of the treatment being tested. Tanks A, B, and C cannot serve as the control group in this experiment as they are all part of the experimental setup and are not kept untreated for comparison.

Correct Answer: C

Rationale: The correct answer is C (50 neutrons). Neutrons are calculated by subtracting the atomic number from the mass number. The mass number represents the total number of protons and neutrons in an atom. Since the atomic number (number of protons) is not given, we use the mass number as a total. Therefore, for an atom with a mass number of 50, it must have 50 neutrons. Choice A (38) is incorrect because it does not match the given mass number. Choice B (88) is incorrect as it is not the correct calculation based on the mass number provided. Choice D (126) is incorrect as it is not the correct calculation based on the mass number provided.

Correct Answer: B

Rationale: The correct answer is B: tongue. The tongue is the muscular organ responsible for processing food into smaller pieces by moving it around the mouth, mixing it with saliva to form a bolus, and pushing the food towards the back of the mouth to swallow. The pharynx (choice A) is the passageway for food and air, the diaphragm (choice C) is a muscle involved in breathing, and the stomach (choice D) is responsible for further digestion of food. The tongue's specific functions in manipulating food and aiding in swallowing make it the correct choice for this question.