ATI TEAS Science Questions

Correct Answer: C

Rationale: To balance the combustion equation CxHy + O2 → xCO2 + y/2 H2O, we need to balance the carbon and hydrogen atoms. The balanced equation for the given combustion is: 2C H4 + 9O2 → 2CO2 + 4H2O. This means that the correct coefficients are 2:9:10:4, which corresponds to choice C. Choice A (1:5:5:2) does not balance the equation correctly, choice B (4:10:20:8) has excessive oxygen and does not balance the equation, and choice D (2:5:10:4) does not provide the correct ratio of oxygen to balance the equation.

Correct Answer: A

Rationale: Synergists are muscles that assist the primary movers (agonists) in completing specific movements (I). Additionally, they stabilize the point of origin and provide extra pull near the insertion, aiding in movement efficiency (II). While synergists may contribute to stability, their primary role is to assist in movement rather than prevent unwanted movement at a joint; hence, options I and II offer the most accurate descriptions of their function. Choice B is incorrect because synergists do not primarily help prevent unwanted movement at a joint (III). Choice C is incorrect as it combines stabilization of the point of origin and preventing unwanted movement, which is not the primary function of synergists.

Correct Answer: B

Rationale: The correct answer is the Integumentary system (Option B). The integumentary system, which includes the skin, hair, nails, and glands, serves various functions such as providing protection against external factors, sensory reception, regulating body temperature (thermoregulation), maintaining water balance (osmoregulation), insulating the body, and absorbing vitamin D from sunlight. The nervous system (Option A) is responsible for transmitting signals throughout the body. The endocrine system (Option C) produces and secretes hormones to regulate bodily functions. The digestive system (Option D) is involved in breaking down food for nutrient absorption. Therefore, the primary functions described in the question align with those of the integumentary system, making it the correct choice.

Correct Answer: B

Rationale: The recessive phenotype appears when an individual has two copies of the recessive allele. In this case, the recessive allele is marked with 'a.' Therefore, the genotype 'aa' would display the recessive phenotype as both alleles are recessive. Choice A (AA) has two dominant alleles, choice C (Aa) has one dominant and one recessive allele, and choice D (aA) represents the same genotype as Aa due to the principle of allele dominance.

Correct Answer: B

Rationale: Adrenaline, also known as epinephrine, is produced by the adrenal glands in response to stress. It helps prepare the body for the 'fight or flight' response by increasing heart rate, dilating airways, and mobilizing energy sources. Choice A, Insulin, is incorrect as it is produced by the pancreas and regulates blood sugar levels. Choice C, Glucagon, is also produced by the pancreas and functions to increase blood glucose levels. Choice D, Thyroxine, is produced by the thyroid gland and regulates metabolism, not specifically in response to stress.