Science TEAS Practice Test

Correct Answer: C

Rationale: The correct answer is C: Repeat the experiment several more times and apply a statistical analysis to the data. This is the most appropriate next step because it allows the researcher to gather more data to ensure the results are consistent. By repeating the experiment multiple times, the researcher can determine if the observed behavior of the bacteria is reliable and not just due to chance. Additionally, applying statistical analysis will help in drawing meaningful conclusions from the data and identifying any patterns or trends. Choice A is incorrect because it overlooks the contradictory result from the fourth experiment, which is crucial information that should not be ignored in scientific reporting. Choice B is also incorrect as it does not address the need for further investigation to validate the results. Choice D is not the best next step as it introduces a new variable (chemical), which could complicate the analysis and may not directly address the observed behavior of the bacteria in response to the initial chemical.

Correct Answer: B

Rationale: To be included in the formation of a scientific conclusion, evidence must be reproducible. This means that the findings can be repeated by other researchers to ensure the validity and reliability of the results. Reproducibility is essential in scientific research to confirm the accuracy of the findings and allow for independent verification. Quantitative evidence, while important in providing numerical data, is not always necessary for forming a scientific conclusion. Qualitative evidence, which describes qualities or characteristics, can also contribute to scientific conclusions. The choice "C: Obvious" is incorrect because scientific evidence may not always be obvious and often requires careful analysis and interpretation. Choice "D: All of the above" is incorrect because not all scientific evidence needs to be quantitative, and while reproducibility is crucial, it is not necessary for evidence to be obvious to be included in forming a scientific conclusion.

Correct Answer: B

Rationale: To calculate the grams of CaCO3 needed, we first find the molar mass of CaCO3: 40.07 (Ca) + 12.01 (C) + (15.99 x 3) (O) = 100.08 g/mol. Next, use the formula: grams = moles x molar mass. Moles = 0.35 M x 0.6 L = 0.21 moles. Therefore, grams = 0.21 moles x 100.08 g/mol = 21.02 g. Hence, the correct answer is B: 19.7 g. Other choices are incorrect due to miscalculation or incorrect conversion.

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: D

Rationale: The correct answer is D: Plasma cells. Plasma cells are a type of white blood cell that produces and secretes antibodies, which are essential for the immune response. Plasma cells are specifically designed to produce antibodies to fight off infections. Bacterial cells (choice A) and viral cells (choice B) do not secrete antibodies as they are pathogens. Lymph cells (choice C) are a general term for various types of white blood cells, including plasma cells, but not all lymph cells secrete antibodies. Plasma cells, on the other hand, are specialized for antibody production, making choice D the correct answer.