HESI A2
Biology HESI A2 Practice Exam Questions
Question 1 of 5
Which of these is not an example of a lipid?
Correct Answer: D
Rationale: Honey is not an example of a lipid because lipids are fat-related molecules that are insoluble in water, while honey is a natural sweet substance made by bees and primarily consists of sugars such as glucose and fructose. Butter, wax, and canola oil are examples of lipids as they are all composed of fat-related molecules that do not dissolve in water.
Question 2 of 5
If a test has poor internal consistency, which statement is true?
Correct Answer: B
Rationale: Correct answer: If a test has poor internal consistency, it means that the items do not correlate or measure similar things. This lack of correlation indicates that the items in the test are not measuring the same underlying construct or concept, leading to unreliable results.
Choice A is incorrect because poor internal consistency is not about producing different results at different times but rather about the lack of correlation among items.
Choice C is incorrect because the issue lies within the test itself, not with different researchers.
Choice D is incorrect because poor internal consistency implies that the items do vary in their measurement, contributing to the unreliability of the test.
Question 3 of 5
RNA is made from DNA through a process called ___________.
Correct Answer: A
Rationale: RNA is made from DNA through a process called transcription. During transcription, an enzyme called RNA polymerase reads the DNA template and synthesizes a complementary RNA molecule. This process is essential for gene expression and allows the information encoded in DNA to be converted into functional RNA molecules.
Choice B, 'synthesis,' is incorrect as it is a general term and does not specifically describe the process of RNA formation from DNA.
Choice C, 'translation,' is incorrect as it refers to the process where the mRNA is used to assemble amino acids during protein synthesis, not the conversion of DNA to RNA.
Choice D, 'replication,' is incorrect as it is the process of making an identical copy of DNA, not converting DNA into RNA.
Question 4 of 5
Most enzymes are made up of what?
Correct Answer: A
Rationale: Most enzymes are made up of proteins. Proteins are large biomolecules composed of amino acids that are vital for the structure and function of enzymes. Enzymes act as catalysts in biochemical reactions, speeding up the rate of chemical reactions in living organisms. They exhibit high specificity and efficiency due to their unique protein structures. Lipids, starches, and simple sugars are not typically the primary components of enzymes, making them incorrect choices.
Question 5 of 5
Which cellular structure is largely protective in function?
Correct Answer: C
Rationale: The correct answer is C: Cell membrane. The cell membrane, also known as the plasma membrane, is largely protective in function as it serves as a selectively permeable barrier that surrounds the cell, providing structural support and helping to maintain cell integrity. It regulates the movement of substances in and out of the cell, thus protecting the cell from harmful external factors while allowing essential nutrients to enter. Mitochondrion (choice
A) is responsible for energy production, not primarily protective. Vacuole (choice
B) is mainly involved in storage and transport. Ribosome (choice
D) is involved in protein synthesis, not protective functions.