Biology HESI A2 2024

Correct Answer: C

Rationale: The correct answer is C: 1 female : 2 males. In this scenario, the male offspring have a 50% chance of inheriting the hemophilia gene from the carrier mother, resulting in a 1:1 ratio of affected males to unaffected males. The female offspring will inherit one normal X chromosome from the father and one affected X chromosome from the mother, making them carriers but not affected. Therefore, the predicted ratio of offspring with the disease is 1 female carrier to 2 affected males. Choices A, B, and D are incorrect because they do not reflect the actual inheritance pattern of hemophilia in this scenario.

Correct Answer: B

Rationale: The correct answer is B: Both are prokaryotes. Rationale: 1. Bacteria and blue-green algae lack a true nucleus, membrane-bound organelles, and have a simpler cellular structure, indicating they are prokaryotes. 2. Prokaryotes are distinct from eukaryotes, which have a true nucleus and membrane-bound organelles. 3. Gymnosperms (choice A) are seed-producing plants, not related to bacteria or blue-green algae. 4. Autotrophs (choice C) can include plants, algae, and some bacteria, but not all bacteria are autotrophs. 5. Pathogens (choice D) are disease-causing agents, not a characteristic that defines the classification of bacteria and blue-green algae.

Correct Answer: C

Rationale: The purpose of phloem tissue in plant stems is to conduct food throughout the plant. Phloem is responsible for transporting sugars, amino acids, and other organic compounds produced through photosynthesis from the leaves to other parts of the plant for growth and energy. This process is known as translocation. Choice A is incorrect because water is transported by xylem tissue, not phloem. Choice B is incorrect as phloem does not conduct light energy. Choice D is incorrect as carbon dioxide is absorbed by the plant through stomata and transported through the plant via diffusion, not through phloem tissue.

Correct Answer: C

Rationale: The correct answer is C because yeast carries out fermentation, producing ethanol and carbon dioxide. During fermentation, yeast breaks down sugars in the dough into ethanol and carbon dioxide gas. The carbon dioxide gas gets trapped in the dough, causing it to rise. Choice A is incorrect because yeast does not engage in photosynthesis. Choice B is incorrect because yeast does not carry out photosynthesis at all. Choice D is incorrect because yeast primarily produces carbon dioxide through fermentation, not aerobic respiration.

Correct Answer: A

Rationale: The correct answer is A: Stamen. The stamen is the male reproductive organ of a flower, producing pollen containing male gametes. The pistil, stigma, and style are all parts of the female reproductive system, involved in receiving pollen and supporting the development of seeds. Therefore, the stamen is of a different "gender" than the others, making it the correct choice. Stigma and style are specifically part of the pistil, which is the female organ of the flower.