Practice TEAS Science Test

Correct Answer: B

Rationale: Cystic fibrosis is the correct answer because it is a genetic condition that primarily affects the respiratory system by causing mucus buildup in the lungs, leading to breathing difficulties and recurrent lung infections. This condition is caused by mutations in the CFTR gene. Asthma (A) is a chronic respiratory condition characterized by inflammation and narrowing of the airways but is not a genetic disorder. Mycosis (C) refers to fungal infections and does not specifically affect the respiratory system. Surfactant Deficiency (D) is a condition where insufficient surfactant is produced in the lungs, leading to respiratory distress in newborns, but it is not primarily a genetic condition affecting the respiratory system.

Correct Answer: A

Rationale: The correct answer is A: To transport oxygen and nutrients. The cardiovascular system is responsible for circulating blood throughout the body to deliver oxygen and nutrients to tissues and organs. This function supports cell metabolism and overall body function. Choice B is incorrect because while the cardiovascular system does play a role in blood pressure regulation, it is not its primary function. Choice C is incorrect as digestion is primarily carried out by the digestive system. Choice D is incorrect as waste filtration is mainly performed by the excretory system.

Correct Answer: A

Rationale: The correct answer is A: Ectoderm. During embryonic development, the nervous system originates from the ectoderm layer. The neural plate forms from the ectoderm, which further develops into the neural tube and neural crest cells, giving rise to the brain, spinal cord, and peripheral nervous system. The other choices, B: Endoderm, C: Gastroderm, and D: Mesoderm, do not give rise to the nervous system. Endoderm forms the innermost layer of organs like the gut, Gastroderm is not a recognized germ layer, and Mesoderm gives rise to structures like muscles, bones, and connective tissues, not the nervous system.

Correct Answer: A

Rationale: Insulin is the correct answer as it helps regulate blood sugar levels by facilitating the uptake of glucose into cells. Adrenaline, cortisol, and melatonin do not directly regulate blood sugar levels like insulin does. Adrenaline primarily affects the fight-or-flight response, cortisol is involved in stress response and metabolism, and melatonin regulates sleep-wake cycles. Insulin's role in blood sugar regulation is crucial for maintaining proper glucose levels in the body.

Correct Answer: B

Rationale: The correct answer is B: Protein. Proteins are macromolecules composed of amino acids, which always contain nitrogen in their structure. Amino acids have an amine group (-NH2), which is where the nitrogen is found. Fatty acids (choice A) do not contain nitrogen in their structure. Lipids (choice C) and carbohydrates (choice D) also do not contain nitrogen in their basic structure. Therefore, protein is the only macromolecule among the choices that will always contain nitrogen.