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: 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: A

Rationale: Beeswax is a lipid because it is a natural substance primarily composed of esters of fatty acids and long-chain alcohols. Lipids are hydrophobic molecules that include fats, oils, and waxes. Beeswax fits this description due to its insolubility in water and its role in providing a protective barrier for bees' hives. Carbohydrates are composed of sugars, proteins are made up of amino acids, and nucleic acids are the building blocks of DNA and RNA. Therefore, choices B, C, and D are incorrect as they do not align with the chemical composition and characteristics of beeswax.

Correct Answer: A

Rationale: The correct answer is A because chlorophyll appears green due to its absorption spectrum. It absorbs light most efficiently in the blue and red regions of the spectrum, while reflecting or transmitting green light. This selective absorption of light wavelengths results in chlorophyll appearing green to our eyes. Choice B is incorrect because chlorophyll does not primarily absorb green light. Choice C is incorrect as chlorophyll actually does absorb green light, just not as efficiently as blue and red light. Choice D is incorrect because chlorophyll primarily absorbs red and blue light, not red light alone.

Correct Answer: D

Rationale: The correct answer is D: genus; species. "Felis" is the genus and "catus" is the species in the scientific name Felis catus. Genus is a broader classification that includes closely related species, while species is the most specific classification level. Kingdom (choice A) is too broad, family (choice A) is at a higher level than species, order (choice B) is too specific, subspecies (choice B) is not part of the scientific name, phylum (choice C) is too broad, and class (choice C) is a higher classification level than species.