Biology HESI A2 2024

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.

Correct Answer: B

Rationale: The correct answer is B because meiosis creates cells with half the chromosomes of the parent cell through two rounds of cell division. This results in gametes with a haploid number of chromosomes. In contrast, mitosis produces identical diploid cells for growth and repair. Choices A, C, and D are incorrect because mitosis forms body cells, telophase occurs in both processes, and spermatogenesis and oogenesis specifically involve meiosis, respectively.

Correct Answer: C

Rationale: The formula represents the process of photosynthesis where carbon dioxide (CO₂) and water (H₂O) are converted into glucose (C₆H₁₂O₆) and oxygen (O₂) in the presence of sunlight. Step 1: 6CO₂ + 6H₂O represent the reactants involved in photosynthesis. Step 2: C₆H₁₂O₆ + 6O₂ represent the products formed during photosynthesis. Therefore, the correct answer is C: Photosynthesis. Other choices are incorrect because: A: Glycolysis involves the breakdown of glucose into pyruvate. B: Cellular respiration involves the breakdown of glucose to produce energy. D: Electronic transport is related to the movement of electrons in cellular respiration, not photosynthesis.

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: D

Rationale: The correct answer is D: Carbohydrates. Glucose is a type of simple sugar and a carbohydrate. Carbohydrates are composed of carbon, hydrogen, and oxygen in a 1:2:1 ratio, which is the molecular formula of glucose (C6H12O6). Proteins (choice A) are composed of amino acids, lipids (choice B) are composed of fatty acids and glycerol, and nucleic acids (choice C) are composed of nucleotides. Therefore, only carbohydrates, specifically glucose, contain the specific molecular structure that characterizes glucose.