HESI A2
Biology HESI A2 Practice Test Questions
Question 1 of 5
Muscles are connected to bones by ______, and bones are connected to each other by ______.
Correct Answer: B
Rationale: Muscles are connected to bones by tendons, which allow the muscle to exert force on the bone for movement. Bones are connected to each other by ligaments, which provide stability and support to the joints between bones. This relationship between muscles, tendons, bones, and ligaments is essential for proper movement and function of the musculoskeletal system.
Choice A is incorrect because muscles are not directly connected to bones; tendons serve as the connection between muscles and bones.
Choice D is incorrect because ligaments connect bones to each other, not muscles to bones.
Question 2 of 5
The force per unit area exerted against a surface by the weight of air above that surface in the Earth's atmosphere is the ______.
Correct Answer: A
Rationale: Atmospheric pressure is the correct term for the force per unit area exerted against a surface by the weight of air above that surface in the Earth's atmosphere. It is commonly measured in units such as pascals, millibars, or inches of mercury. Barometric density and aneroid pressure are not accurate descriptions for this phenomenon. Barometric density refers to the density of the atmosphere at a particular location, while aneroid pressure is linked to a type of barometer but not a comprehensive term for the force exerted by the weight of air.
Question 3 of 5
In a phospholipid molecule, the head:
Correct Answer: D
Rationale: The head of a phospholipid is hydrophilic (water-loving) and is located on the outer side of the lipid bilayer, interacting with water molecules. This arrangement positions the hydrophobic tails inward, away from water.
Therefore, the correct answer is D.
Choice A is incorrect because the head is hydrophilic, not hydrophobic.
Choice B is incorrect as the head is on the outer side, not the inner side of the layer.
Question 4 of 5
The phases of mitosis include:
Correct Answer: C
Rationale: The correct phases of mitosis are prophase, prometaphase, metaphase, anaphase, and telophase. Prophase is the first phase where chromatin condenses into chromosomes, the nuclear envelope breaks down, and the mitotic spindle forms. Prometaphase follows prophase, involving the full disintegration of the nuclear envelope and the attachment of spindle fibers to the kinetochores of the chromosomes. Metaphase is where chromosomes align along the metaphase plate. Anaphase is the phase where sister chromatids separate and move towards opposite poles. Telophase marks the final stage of mitosis, involving the decondensation of chromosomes and the reformation of the nuclear envelope.
Choice A is incorrect because it includes interphase, which is not a phase of mitosis.
Choice B is incorrect as it repeats prophase, which is the initial phase.
Choice D is incorrect because it includes interphase and repeats prophase.
Question 5 of 5
A cell that does not contain membrane-bound organelles or a defined nucleus would be classified as:
Correct Answer: C
Rationale: A cell that does not contain membrane-bound organelles or a defined nucleus is classified as prokaryotic. Prokaryotic cells lack a true nucleus, and their genetic material is typically found in a region called the nucleoid. Examples of prokaryotic organisms include bacteria and archaea. Eukaryotic cells, on the other hand, contain membrane-bound organelles and a true nucleus, distinguishing them from prokaryotic cells. Embryonic and symbiotic classifications are not directly related to the presence of organelles or a nucleus in cells.