which of the following best describes one of the roles of rna

ATI TEAS 7

ATI TEAS 7 Science Practice Test

1. Which of the following best describes one of the roles of RNA?

A. Manufacturing the proteins needed from DNA
B. Creating the bonds between the elements that make up DNA
C. Sending messages about the correct sequence of proteins in DNA
D. Forming the identifiable double helix shape of DNA

Correct answer: C

Rationale: The correct answer is C. RNA serves as a messenger that carries instructions from DNA for protein synthesis. It does not manufacture proteins directly from DNA (choice A), create bonds within DNA (choice B), or form the double helix structure of DNA (choice D). Therefore, the primary role of RNA is to convey information about the correct sequence of proteins to be synthesized based on the DNA sequences it receives.

2. Which of the following nucleobases does not exist in RNA?

A. Uracil
B. Thymine
C. Cytosine
D. Guanine

Correct answer: B

Rationale: The correct answer is 'B: Thymine'. Thymine is a nucleobase found in DNA but is replaced by uracil in RNA. RNA contains Uracil, Cytosine, and Guanine as its nucleobases. Cytosine and Guanine are present in both DNA and RNA, while Thymine is exclusive to DNA and Uracil is specific to RNA.

3. Which part of the brain is responsible for coordinating various sensory inputs, regulating sleep, and maintaining wakefulness?

A. Cerebrum
B. Hypothalamus
C. Medulla oblongata
D. Reticular formation

Correct answer: D

Rationale: The reticular formation is a network of neurons located in the brainstem that plays a crucial role in regulating sleep-wake cycles, coordinating various sensory inputs, and maintaining wakefulness. It acts as a filter for incoming sensory information and helps in directing attention to important stimuli. The other options, the cerebrum, hypothalamus, and medulla oblongata, are important structures in the brain but are not primarily responsible for the specific functions mentioned in the question. The cerebrum is mainly involved in higher brain functions such as thinking and voluntary movements. The hypothalamus is responsible for regulating body temperature, hunger, and thirst, among other functions. The medulla oblongata is essential for controlling vital autonomic functions like breathing and heart rate.

4. What is the balanced chemical equation for the reaction between sulfuric acid (H2SO4) and potassium hydroxide (KOH)?

A. H2SO4 + KOH → K2SO4 + H2O
B. 2H2SO4 + 2KOH → 2K2SO4 + 2H2O
C. H2SO4 + 2KOH → K2SO4 + 2H2O
D. H2SO4 + 2KOH → K2SO4 + H2O

Correct answer: C

Rationale: When sulfuric acid (H2SO4) reacts with potassium hydroxide (KOH), it forms potassium sulfate (K2SO4) and water (H2O). To balance the equation, 2 KOH molecules are required to react with 1 H2SO4 molecule, resulting in 1 K2SO4 molecule and 2 H2O molecules. Therefore, the balanced chemical equation is H2SO4 + 2KOH → K2SO4 + 2H2O, which corresponds to option C. Choice A is incorrect because it does not account for the correct stoichiometry between the reactants and products. Choice B incorrectly doubles all the molecules in the reaction, leading to an unbalanced equation. Choice D incorrectly balances the equation with 1 KOH molecule instead of the required 2 KOH molecules, making it unbalanced. Thus, option C is the correct balanced chemical equation for the reaction between sulfuric acid and potassium hydroxide.

5. Which of the following is NOT a function of the forebrain?

A. To regulate blood pressure and heart rate
B. To perceive and interpret emotional responses like fear and anger
C. To perceive and interpret visual input from the eyes
D. To integrate voluntary movement

Correct answer: A

Rationale: The correct answer is A. The forebrain is primarily responsible for higher cognitive functions such as perception, interpretation, and integration of sensory information, emotional responses, and voluntary movements. Functions like regulating blood pressure and heart rate are mainly controlled by various structures in the brainstem, such as the medulla oblongata and the pons. Choices B, C, and D are all functions associated with the forebrain. Choice B relates to the limbic system, which is part of the forebrain responsible for emotional responses. Choice C corresponds to the occipital lobe in the forebrain, involved in processing visual information. Choice D involves the motor cortex and other areas in the forebrain that coordinate voluntary movements.