ATI TEAS Practice Science Test

Correct Answer: C

Rationale: The correct order of airflow in the lungs is Trachea, Bronchi, Bronchioles, Alveoli (Option C). The rationale is: 1. Air enters through the trachea. 2. Trachea branches into bronchi. 3. Bronchi further divide into bronchioles. 4. Bronchioles lead to the alveoli where gas exchange occurs. Summary: Option A is incorrect as it starts with bronchi before the trachea. Option B is incorrect as it reverses the order of bronchioles and bronchi. Option D is incorrect as it places alveoli before bronchioles and trachea before bronchi.

Correct Answer: C

Rationale: The correct answer is C because fetal waste is passed down the umbilical cord to the mother's circulatory system. The developing fetus eliminates metabolic wastes primarily through the placenta, which acts as a filter between the fetal and maternal circulatory systems. Metabolic wastes from the fetus, such as carbon dioxide and urea, diffuse through the placenta into the mother's bloodstream for elimination by her kidneys and lungs. This process ensures that the fetus's metabolic wastes are effectively removed without burdening its own developing organs. Choices A, B, and D are incorrect: A: The developing fetus does produce metabolic wastes, which need to be eliminated for proper development. B: Fetal waste does not pass through the mother's digestive system; it would be harmful to both the mother and fetus. D: Fetal waste does not exit the mother's body via the vagina; this is not a mechanism for waste elimination in utero.

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: Paracrine. This is because somatostatin is a chemical signal that acts locally on neighboring cells within the pancreas to inhibit insulin secretion. Paracrine signals are released by one cell and act on nearby cells of the same tissue. Autocrine signals act on the same cell that produced them, which is not the case here. Neuromodulators modulate the activity of neurons, not endocrine cells like in this scenario. Pheromones are chemical signals that are used for communication between individuals of the same species, not within the same organism like in this case.

Correct Answer: A

Rationale: The correct answer is A: Uterus, cervix, vagina. During childbirth, the fetus travels from the uterus through the cervix and then out through the vagina. The uterus is where the fetus develops, the cervix dilates to allow passage, and the vagina is the birth canal. The other choices are incorrect because they do not follow the correct route of the fetus during childbirth. Choice B (Cervix, uterus, vagina) is incorrect as the fetus does not move from the cervix to the uterus during childbirth. Choice C (Uterus, vas deferens, vagina) is incorrect as the vas deferens is part of the male reproductive system and not involved in childbirth. Choice D (Ovary, fallopian tube, uterus) is incorrect as this represents the path of the egg during fertilization, not the route of the fetus during childbirth.