HESI A2
HESI A2 Version 1 Biology Questions
Question 1 of 5
The cellular membrane consists of a bilayer of which substances?
Correct Answer: B
Rationale: The cellular membrane is primarily composed of a phospholipid bilayer, forming the structure that regulates entry and exit.
Question 2 of 5
What does the mitochondrion produce that causes it to often be called the powerhouse of the cell?
Correct Answer: A
Rationale: The mitochondrion produces ATP (adenosine triphosphate), which is the primary energy currency of the cell. This energy production is why mitochondria are referred to as the powerhouse of the cell. ATP generated by mitochondria is essential for various cellular processes, such as muscle contraction, cell division, and macromolecule synthesis, making it a crucial organelle for cell function.
Question 3 of 5
What is the first step in the process of respiration?
Correct Answer: D
Rationale: The correct answer is Glycolysis. Glycolysis is the initial step in cellular respiration where glucose is broken down into pyruvate, producing a small amount of ATP and NADH in the cytoplasm. This step is crucial as it initiates the breakdown of glucose, setting the stage for further energy production in subsequent stages like the Krebs cycle and electron transport chain.
Question 4 of 5
Which set is correctly listed for characteristic chromosome number, and most of their cells have a complete set of these chromosomes?
Correct Answer: D
Rationale: The correct order from largest to smallest is Phylum, Order, Genus, Species. In biological classification, the hierarchy of taxonomic ranks is structured such that phylum is the broadest category, followed by order, genus, and species, which is the most specific. When looking at the characteristic chromosome number, most cells have a complete set of chromosomes, and this order aligns with the genetic similarity and differences observed in organisms.
Question 5 of 5
In the presence of which molecule does aerobic respiration occur?
Correct Answer: A
Rationale: Aerobic respiration is a process that requires oxygen to efficiently convert glucose into carbon dioxide, water, and ATP. Oxygen plays a critical role in this metabolic pathway by acting as the final electron acceptor in the electron transport chain, allowing the production of ATP through oxidative phosphorylation. Therefore, oxygen is the essential molecule for aerobic respiration to take place.