Biology HESI A2 Practice Test

Correct Answer: C

Rationale: Correct Answer: C Rationale: 1. Sexual reproduction involves two cells (sperm and egg) contributing genetic material to offspring, leading to genetic variation. 2. Greater genetic variation in offspring helps in adapting to changing environments and enhances species survival. 3. Asexual reproduction involves a single parent cell dividing to produce genetically identical offspring. 4. Option A is incorrect as sexual reproduction does not result in half of the cells being identical to the original cell. 5. Option B is incorrect as asexual reproduction does not result in greater variation, it produces genetically identical offspring. 6. Option D is incorrect as sexual reproduction involves two cells contributing genetic material, leading to variation.

Correct Answer: C

Rationale: The correct answer is C (bb) because tan fur is the recessive phenotype controlled by the tan allele (b). Since the black allele (B) exhibits complete dominance, a dog must have two copies of the tan allele (bb) to have a tan fur phenotype. Choice A (BB) and B (Bb) would result in black fur, not tan. Choice D (Not enough information) is incorrect as the question provides enough information to determine the correct genotype based on the phenotype given.

Correct Answer: B

Rationale: The correct answer is B: Smooth, skeletal, cardiac. Smooth muscle tissue is found in organs and blood vessels, skeletal muscle tissue is attached to bones for movement, and cardiac muscle tissue is found in the heart. The other choices are incorrect because they do not accurately represent the types of muscle tissue in the human body. Choice A includes organs and structures that are not muscle tissues. Choice C lists a neuron (nerve cell), epithelial (covering and lining tissue), and collagen (connective tissue), which are not types of muscle tissue. Choice D is incorrect as it does not provide the correct types of muscle tissue.

Correct Answer: A

Rationale: Adenine is a purine base because it has a double-ring structure, which is a characteristic of purines. It pairs with thymine in DNA and uracil in RNA. Cytosine, thymine, and guanine are pyrimidines, which have a single-ring structure. Therefore, the correct answer is A. Cytosine, thymine, and guanine are incorrect choices as they are pyrimidines.

Correct Answer: C

Rationale: Correct Answer: C Rationale: 1. Sexual reproduction involves two cells (sperm and egg) contributing genetic material to offspring, leading to genetic variation. 2. Greater genetic variation in offspring helps in adapting to changing environments and enhances species survival. 3. Asexual reproduction involves a single parent cell dividing to produce genetically identical offspring. 4. Option A is incorrect as sexual reproduction does not result in half of the cells being identical to the original cell. 5. Option B is incorrect as asexual reproduction does not result in greater variation, it produces genetically identical offspring. 6. Option D is incorrect as sexual reproduction involves two cells contributing genetic material, leading to variation.