Science TEAS Practice Test

Correct Answer: B

Rationale: The correct answer is B: A gene. A gene is the smallest unit that can encode for a trait because it is a specific sequence of nucleotides in the DNA that provides instructions for a particular trait or function. Genes determine our physical characteristics and traits. A codon (choice A) is a sequence of three nucleotides that code for a specific amino acid in protein synthesis, not a complete trait. A nucleotide (choice C) is the basic building block of DNA, but it is not capable of encoding for a trait on its own. A chromosome (choice D) is made up of DNA and contains multiple genes, so it is not the smallest unit that can encode for a trait.

Correct Answer: B

Rationale: The correct answer is B: A model. A model is a representation of a natural pattern or occurrence that simplifies complex systems to make them easier to understand and study. Models can simulate natural phenomena that are difficult or impossible to experience directly, allowing scientists to make predictions and test hypotheses. The other choices are incorrect because: A: A theory is an explanation based on evidence and reasoning, not necessarily something difficult to experience directly. C: A law describes a recurring phenomenon but may not involve a representation or simulation of the phenomenon. D: An observation is a direct act of seeing or noting something, not a representation of a complex natural pattern.

Correct Answer: C

Rationale: The correct answer is C: An inference. This is because the statement "someone must have forgotten to water it" is not a direct observation but a conclusion drawn based on the observed condition of the dead flower. In making this statement, the speaker is connecting the lack of water to the flower being dead, which requires logical reasoning. A: A classification - This choice does not apply as the statement does not categorize or group anything. B: An observation - While the initial part of the statement is an observation (the flower is dead), the second part goes beyond just stating what is observed to drawing a conclusion based on that observation. D: A collection - This choice does not make sense in this context as the statement does not involve gathering or assembling items.

Correct Answer: D

Rationale: The correct answer is D: Veins. Veins have the lowest blood pressure among the structures listed. This is because veins have thinner walls and larger lumens compared to arteries and arterioles, which results in less resistance to blood flow and lower pressure. Venules are small vessels that connect capillaries to veins and have slightly higher pressure than veins. Arteries and arterioles have thicker walls and smaller lumens to withstand the higher pressure of blood ejected by the heart. Therefore, veins have the lowest blood pressure due to their structural characteristics.

Correct Answer: B

Rationale: The correct answer is B. If an organism is AB, it means they have alleles A and B. In gametes, each gamete carries only one allele. Therefore, gametes with AA are not possible as they lack the B allele. Gametes with AB are possible since they can carry either A or B allele. Gametes with BB are not possible as they lack the A allele. Gametes with AB are possible as they can carry either A or B allele.