which of the following statements best defines an 1627799

ATI TEAS 7

ATI TEAS Science Test

1. Which of the following statements best defines an organelle?

A. Layer of polysaccharides outside the plasma membrane of cells.
B. Abnormal infectious proteins.
C. Specialized structures within a cell.
D. Collection of tissues used to serve a specific function.

Correct answer: C

Rationale: The correct answer is C: 'Specialized structures within a cell.' An organelle is a specialized subunit within a cell that has a specific function. Organelles are membrane-bound structures found within the cytoplasm of eukaryotic cells, each performing distinct roles that contribute to the overall functioning of the cell. Choices A, B, and D are incorrect. Option A describes the glycocalyx, which is a layer of polysaccharides outside the plasma membrane of cells. Option B refers to prions, abnormal infectious proteins. Option D defines an organ, a collection of tissues used to serve a specific function, rather than an organelle within a cell.

2. What is the perimeter of a rectangle with a length of 7 cm and a width of 3 cm?

A. 21 cm
B. 10 cm
C. 14 cm
D. 20 cm

Correct answer: D

Rationale: To find the perimeter of a rectangle, you add the lengths of all its sides. In this case, the formula for the perimeter of a rectangle is 2*(length + width). Substituting the given values, we get: 2*(7 cm + 3 cm) = 2*(10 cm) = 20 cm. Therefore, the correct answer is 20 cm. Choice A (21 cm) is incorrect because it is the sum of the individual sides rather than the perimeter. Choice B (10 cm) is incorrect because it only represents one side of the rectangle. Choice C (14 cm) is incorrect as it is not the total perimeter of the rectangle.

3. What is the importance of RNA splicing?

A. Removes introns from the mRNA molecule
B. Adds the poly-A tail to the mRNA molecule
C. Activates the mRNA molecule for translation
D. Modifies the structure of the protein

Correct answer: A

Rationale: RNA splicing is a crucial process in gene expression where non-coding regions called introns are removed from the pre-mRNA molecule, and the remaining coding regions called exons are joined together to form the mature mRNA molecule. This process ensures that only the protein-coding sequences are retained in the mRNA for translation, allowing for the production of functional proteins. Therefore, option A is the correct answer as it accurately describes the importance of RNA splicing in generating mature mRNA molecules for protein synthesis. B) Adding the poly-A tail to the mRNA molecule is a post-transcriptional modification that occurs after RNA splicing and is not directly related to the process of removing introns. C) Activating the mRNA molecule for translation is typically achieved through the addition of a 5' cap and the poly-A tail, rather than through RNA splicing. D) Modifying the structure of the protein is not directly related to the process of RNA splicing, which primarily focuses on mRNA maturation by removing non-coding introns.

4. What unit is used to measure density in the metric system?

A. grams per cubic meter (g/mÂ³)
B. grams per liter (g/L)
C. grams per cubic centimeter (g/cmÂ³)
D. grams per square meter (g/mÂ²)

Correct answer: A

Rationale: Density is measured in grams per cubic meter (g/mÂ³) in the metric system. This unit represents the amount of mass (in grams) per unit volume (cubic meter). Choice B, grams per liter (g/L), is incorrect as density is not typically measured in liters. Choice C, grams per cubic centimeter (g/cmÂ³), is a common unit for density but not the standard SI unit. Choice D, grams per square meter (g/mÂ²), is a unit for surface density, not volumetric density. Therefore, the correct unit for measuring density in the metric system is grams per cubic meter (g/mÂ³).

5. Based on the language in the passage, which one of the following scenarios is correct?

A. The writer is a professional in a business environment.
B. The writer is a researcher writing for a scientific journal.
C. The writer is a student writing a first draft of a paper.
D. The writer is an author of literature.

Correct answer: D

Rationale: The correct answer is D. The passage's descriptive and narrative style, focusing on character and setting details, suggests that the writer is an author of literature. Choice A is incorrect because there is no indication of a business environment or professional context in the passage. Choice B is incorrect as the passage does not align with the technical or formal language typical of scientific journals. Choice C is incorrect as the passage does not reflect the style or content common in student papers, which are usually more structured and formal.