Biology HESI A2 Practice Exam

Correct Answer: C

Rationale: The correct answer is C: rod-shaped. Bacillus subtilis is a type of bacteria known for its rod-shaped morphology. This shape is characteristic of this specific bacterium and distinguishes it from other bacterial shapes such as spiral (A), globular (B), and grape-like clusters (D). The rod shape of Bacillus subtilis allows it to efficiently reproduce and adapt to various environments. This morphology also plays a role in its motility and survival strategies. By understanding the distinct rod-shaped morphology of Bacillus subtilis, one can accurately identify and differentiate it from other bacterial species.

Correct Answer: A

Rationale: The correct answer is A: proteins. Enzymes are biological catalysts that facilitate chemical reactions in living organisms. Proteins are made up of amino acids, which are essential for the structure and function of enzymes. Enzymes have specific 3D structures that allow them to interact with substrates and speed up reactions. Lipids (B), starches (C), and simple sugars (D) are not typically components of enzymes. Lipids are fats, starches are carbohydrates, and simple sugars are monosaccharides, none of which provide the structural and functional properties required for enzyme activity.

Correct Answer: C

Rationale: The correct answer is C: Glucose. In photosynthesis, glucose is not a reactant but a product synthesized as a result of the process. Water (A), light energy (B), and carbon dioxide (D) are all reactants in photosynthesis. Water is split into oxygen and hydrogen ions, light energy is absorbed by chlorophyll to initiate the process, and carbon dioxide is converted into glucose through a series of biochemical reactions. Therefore, glucose is the only option that is not a reactant in photosynthesis.

Correct Answer: A

Rationale: The correct answer is A: Anther. The anther is the part of the plant responsible for producing pollen. It is located at the top of the stamen, one of the male reproductive parts of a flower. Pollen contains the male gametes necessary for fertilization. The other choices, B: Style, C: Stigma, and D: Pistil, are all parts of the female reproductive system of a flower. The style is the tube connecting the stigma to the ovary, the stigma is the sticky part that receives pollen, and the pistil is the entire female reproductive structure. Therefore, they are not involved in the production of pollen.

Correct Answer: A

Rationale: The correct answer is A: Shelf fungus. Shelf fungi reproduce via spore formation, a process where specialized reproductive cells are released into the environment to germinate and grow into new individuals. This method is characteristic of fungi and some plants. The other choices, B: Lemon tree, C: Smallmouth bass, and D: Staphylococcus, reproduce through different mechanisms such as seeds, spawning, and binary fission, respectively. Spore formation is unique to certain organisms like fungi, making option A the correct answer.