what is the process by which rna molecules are modified after transcription but before translation

ATI TEAS 7

TEAS 7 science practice

1. What is the process by which RNA molecules are modified after transcription but before translation?

A. Replication
B. Splicing
C. Editing
D. Packaging

Correct answer: B

Rationale: B) Splicing is the correct answer. Splicing is the process by which non-coding regions (introns) are removed from pre-mRNA, and the remaining coding regions (exons) are joined together to form mature mRNA. This modification occurs after transcription but before translation. A) Replication is incorrect as replication is the process by which DNA is copied to produce a new DNA molecule, not RNA modifications. C) Editing may involve RNA editing, but it is not commonly used to describe the modification of RNA molecules after transcription. D) Packaging is not the correct term as it refers to the condensation and organization of DNA into chromatin in eukaryotic cells, not the modification of RNA molecules.

2. Which of the following is NOT a major component of a healthy blood pressure reading?

A. Systolic pressure (peak pressure during ventricular contraction)
B. Diastolic pressure (pressure within arteries during ventricular relaxation)
C. Pulse pressure (difference between systolic and diastolic pressure)
D. Blood oxygen saturation levels. While blood oxygen levels are crucial for overall health, they are not directly reflected in a blood pressure reading.

Correct answer: D

Rationale: Blood oxygen saturation levels are essential for overall health but are not directly part of a blood pressure reading. A healthy blood pressure reading consists of systolic pressure, diastolic pressure, and pulse pressure. Systolic pressure represents the peak pressure during ventricular contraction, diastolic pressure reflects the pressure within arteries during ventricular relaxation, and pulse pressure is the difference between systolic and diastolic pressure. These components collectively provide information about the pressure variations within the arteries throughout the cardiac cycle phases, contributing to the assessment of cardiovascular health. Therefore, choice D, blood oxygen saturation levels, is not a major component of a healthy blood pressure reading and is the correct answer. Choices A, B, and C are major components of a healthy blood pressure reading and directly relate to the pressure variations within the arteries during different phases of the cardiac cycle.

3. The spleen, a large lymphatic organ, is located in the:

A. Chest
B. Abdomen
C. Pelvis
D. Head and neck

Correct answer: B

Rationale: The spleen is located in the abdomen, specifically in the upper left part of the abdomen, under the ribcage and above the stomach. It is an important organ in the lymphatic system responsible for filtering blood, storing blood cells, and fighting infection. It is not located in the chest, pelvis, or head and neck regions. Therefore, the correct answer is 'B: Abdomen.' Choices 'A: Chest,' 'C: Pelvis,' and 'D: Head and neck' are incorrect as the spleen is not situated in these anatomical areas.

4. What is the main difference between a telescope and a microscope?

A. Telescopes magnify distant objects, while microscopes magnify small objects.
B. Telescopes use lenses, while microscopes use mirrors.
C. Telescopes collect light, while microscopes emit light.
D. They both magnify objects but serve different purposes.

Correct answer: A

Rationale: The main difference between a telescope and a microscope lies in their primary functions. Telescopes are specifically designed to magnify and observe distant objects like stars, planets, and galaxies, making them essential tools for astronomy. In contrast, microscopes are utilized to magnify and study small objects such as cells, bacteria, and other microscopic organisms in fields like biology and medicine. Therefore, the key distinction is that telescopes focus on magnifying distant objects, while microscopes are tailored for magnifying small objects. Choice B is incorrect because while some microscopes may use mirrors in certain designs, the primary component is typically lenses. Choice C is incorrect as telescopes collect and focus light for observation, while microscopes use light to illuminate and magnify objects. Choice D is incorrect because while both instruments magnify objects, their main purposes and the types of objects they focus on are distinctly different.

5. What is the cycle of infection?

A. Reservoir host, means of exit, means of transmission, means of entrance, susceptible host
B. Entry point, transmission, replication, exit, susceptible host
C. Susceptible host, replication, transmission, entry, exit
D. Transmission, replication, entry, exit, susceptible host

Correct answer: A

Rationale: The correct answer is A: 'Reservoir host, means of exit, means of transmission, means of entrance, susceptible host.' This cycle of infection involves the pathogen starting in a reservoir host, exiting through a means, being transmitted to another host, entering the new host through a means, and ultimately infecting the susceptible host. Choices B, C, and D are incorrect because they do not follow the correct sequence of events in the cycle of infection.