what are the differences between rna and dna

ATI TEAS 7

TEAS 7 science practice

1. What are the differences between RNA and DNA?

A. Both have the same structure and function.
B. RNA is single-stranded, while DNA is double-stranded.
C. RNA contains ribose sugar, while DNA contains deoxyribose sugar.
D. RNA has adenine and guanine, while DNA has thymine and cytosine.

Correct answer: B

Rationale: A) This statement is incorrect. RNA and DNA have different structures and functions. RNA is involved in protein synthesis and other cellular processes, while DNA stores genetic information. B) This statement is correct. RNA is typically single-stranded, while DNA is double-stranded, forming a double helix structure. C) This statement is correct. RNA contains ribose sugar in its backbone, while DNA contains deoxyribose sugar. D) This statement is incorrect. RNA contains adenine, guanine, cytosine, and uracil, while DNA contains adenine, guanine, cytosine, and thymine. Choice B is the correct answer as it accurately describes one of the key differences between RNA and DNA, emphasizing their structural disparity in terms of single-strandedness for RNA and double-strandedness for DNA. Choices A, C, and D contain inaccuracies regarding the structural and compositional distinctions between RNA and DNA, making them incorrect choices.

2. Which structure, located between the pons and the spinal cord, plays a crucial role in coordinating movements, maintaining balance, and posture?

A. Thalamus
B. Medulla oblongata
C. Cerebellum
D. Hypothalamus

Correct answer: C

Rationale: The correct answer is the cerebellum. The cerebellum, located between the pons and the spinal cord, is responsible for coordinating movements, maintaining balance, and posture. The thalamus functions in relaying sensory and motor signals to the cerebral cortex, the medulla oblongata controls vital autonomic functions such as breathing and heart rate, and the hypothalamus regulates various bodily functions like temperature and hunger. Therefore, the cerebellum is the structure that specifically handles coordination, balance, and posture.

3. Which of the following is NOT a risk factor for developing atherosclerosis?

A. High blood pressure
B. High levels of LDL cholesterol
C. Regular physical activity
D. Smoking

Correct answer: C

Rationale: Regular physical activity is not a risk factor for developing atherosclerosis; in fact, it is associated with a reduced risk. High blood pressure, high levels of LDL cholesterol, and smoking are all known risk factors for atherosclerosis. Regular physical activity plays a crucial role in improving cardiovascular health, reducing the risk of atherosclerosis, and maintaining overall well-being. Therefore, the correct answer is regular physical activity (choice C).

4. What is the term for a solution that has a lower concentration of solute compared to another solution?

A. Saturated solution
B. Unsaturated solution
C. Dilute solution
D. Concentrated solution

Correct answer: B

Rationale: An unsaturated solution is the term used for a solution that has a lower concentration of solute compared to another solution. In an unsaturated solution, more solute could still be dissolved. The other options are incorrect. A saturated solution (A) contains the maximum amount of solute that can be dissolved and is in equilibrium with undissolved solute. A dilute solution (C) has a low concentration of solute, but it does not imply a comparison to another solution. A concentrated solution (D) has a high concentration of solute compared to the solvent, which is opposite to what is described in the question.

5. Which type of energy is possessed by an object due to its position or configuration?

A. Kinetic energy
B. Thermal energy
C. Potential energy
D. Electrical energy

Correct answer: C

Rationale: Potential energy is the energy that an object possesses due to its position or configuration. It is considered stored energy that can be converted into other forms of energy to do work. When an object is lifted against gravity or compressed, it gains potential energy. Kinetic energy, the incorrect choice A, is the energy of motion possessed by an object. Thermal energy, the incorrect choice B, is related to the temperature of an object due to the motion of its particles. Electrical energy, the incorrect choice D, is related to the flow of electric charge in a circuit or system. Therefore, the correct answer is potential energy as it is associated with an object's position or configuration.