which of the following is not true about dna

ATI TEAS 7

Practice Science TEAS Test

1. Which of the following statements is NOT true about DNA?

A. DNA contains the nucleotides A, T, C, G and is read 5' to 3'.
B. DNA contains genetic information and is tightly coiled with proteins to form chromosomes.
C. DNA contains the nucleotides A, T, C, G and is read 3' to 5'.
D. DNA is a double-stranded molecule connected by hydrogen bonds.

Correct answer: C

Rationale: The correct answer is C because DNA is typically read from the 5' end to the 3' end, not from 3' to 5'. Choices A, B, and D are all true statements about DNA. DNA contains the nucleotides A, T, C, G and is read in a 5' to 3' direction. DNA also contains genetic information and is tightly coiled with proteins to form chromosomes. Additionally, DNA is a double-stranded molecule connected by hydrogen bonds.

2. Which of the following describes an experiment?

A. The final math grades for a group of students passing through each year of elementary school are examined.
B. The health trends of smokers in a small random sample are examined.
C. Citizens in a local community are surveyed to determine concerns related to the next election.
D. The effects of a new drug are tested on a group of participants.

Correct answer: D

Rationale: Option D describes an experiment because it involves testing the effects of a new drug on a group of participants. In an experiment, researchers intentionally manipulate an independent variable (in this case, the new drug) to observe its effects on a dependent variable (the participants' health outcomes). This method allows for establishing cause-and-effect relationships between variables, which is a key characteristic of experimental research design. Choices A, B, and C do not represent experiments. Choice A involves observational analysis of math grades, choice B involves observational analysis of health trends, and choice C involves a survey, none of which involve manipulating variables to establish cause-and-effect relationships.

3. Which of the following is NOT a common symptom of pregnancy?

A. Fatigue
B. Nausea
C. Increased urination
D. Loss of appetite

Correct answer: D

Rationale: The correct answer is D, 'Loss of appetite.' Loss of appetite is not a common symptom of pregnancy. In fact, many pregnant individuals experience an increase in appetite due to hormonal changes and increased energy needs during pregnancy. Fatigue, nausea, and increased urination are more commonly reported symptoms during pregnancy. Fatigue is often experienced due to hormonal changes and the body's increased metabolic demands during pregnancy. Nausea, commonly known as morning sickness, is a well-known symptom experienced by many pregnant individuals. Increased urination is a common symptom in pregnancy due to hormonal changes leading to increased blood flow to the kidneys and increased fluid processing by the body.

4. In the human skeleton, which of the following lists some of the vertebrae in descending order?

A. Atlas, axis, thoracic, lumbar, sacral, coccyx.
B. Axis, sacral, coccyx, atlas, lumbar, thoracic.
C. Thoracic, sacral, lumbar, axis, coccyx, atlas.
D. Coccyx, lumbar, axis, sacral, thoracic, atlas.

Correct answer: A

Rationale: The correct order of some of the vertebrae in the human skeleton in descending order is Atlas, Axis, Thoracic, Lumbar, Sacral, Coccyx. This sequence follows the typical arrangement from the top of the spine down towards the pelvis. Choice B is incorrect as it does not follow the descending order of vertebrae. Choice C is incorrect as it starts with Thoracic which is not the first vertebra in the descending order. Choice D is incorrect as it starts with Coccyx which is the last vertebra in the descending order.

5. How many moles of oxygen are required to completely react with 5 moles of propane (C3H8) in the combustion reaction?

A. 5 moles
B. 10 moles
C. 15 moles
D. 20 moles

Correct answer: C

Rationale: In the balanced chemical equation for the combustion of propane (C3H8): C3H8 + 5O2 â†’ 3CO2 + 4H2O, 1 mole of propane (C3H8) reacts with 5 moles of oxygen (O2). To determine the moles of oxygen required to react with 5 moles of propane, we use the molar ratio: 5 moles propane x 5 moles oxygen / 1 mole propane = 25 moles oxygen. However, since the question specifically asks for the moles of oxygen needed to react with 5 moles of propane, the correct answer is 15 moles of oxygen. Choice A, 5 moles, is incorrect because this is the amount of propane provided, not the oxygen required. Choice B, 10 moles, is incorrect as it does not correspond to the molar ratio in the balanced equation. Choice D, 20 moles, is incorrect as it is not in line with the stoichiometry of the reaction.