HESI A2
HESI A2 Biology Practice Test
1. The two catabolic pathways that lead to cellular energy production are:
- A. fermentation and protein synthesis
- B. cellular respiration and glycolysis
- C. fermentation and glycolysis
- D. cellular respiration and fermentation
Correct answer: D
Rationale: The correct answer is D: cellular respiration and fermentation. Cellular respiration involves the breakdown of glucose in the presence of oxygen to produce ATP, which is the primary source of energy for cells. Fermentation, on the other hand, occurs in the absence of oxygen and produces ATP through glycolysis followed by specific fermentation pathways. Choices A, B, and C are incorrect. Protein synthesis is a biosynthetic process, not a catabolic pathway for energy production. Glycolysis is a common step in both cellular respiration and fermentation, so it is not a pair of distinct catabolic pathways. Therefore, the most accurate pairing of catabolic pathways for cellular energy production is cellular respiration and fermentation.
2. Why is polarity the most important characteristic of water?
- A. the results of the polarity are hydrogen bonding, a high specific heat value, and its versatile solvent properties
- B. the results of the polarity are covalent bonding, a low specific heat value, and its versatile solvent properties
- C. the results of the polarity are ionic bonding, a high specific heat value, and its versatile solvent properties
- D. the results of the polarity are hydrogen bonding, a low specific heat value, and its versatile solvent properties
Correct answer: A
Rationale: Polarity is the most important characteristic of water because it results in hydrogen bonding, a high specific heat value, and its versatile solvent properties. These unique properties enable water to form hydrogen bonds with other substances, resist temperature changes, and dissolve a wide variety of solutes, making it essential for life processes. Choice B is incorrect because water exhibits hydrogen bonding, not covalent bonding. Choice C is incorrect as water does not form ionic bonds. Choice D is incorrect because water has a high, not low, specific heat value, which is vital for its role in temperature regulation.
3. Which of the following structures is not directly involved in translation?
- A. tRNA
- B. mRNA
- C. ribosome
- D. DNA
Correct answer: D
Rationale: The correct answer is 'D: DNA.' DNA is not directly involved in translation, which is the process of synthesizing proteins from mRNA. tRNA carries amino acids to the ribosome, mRNA provides the template for protein synthesis, and ribosomes are the cellular machinery where translation occurs. DNA's main role is in transcription, where it serves as the template for mRNA synthesis, not in translation.
4. What organelle is responsible for packaging, processing, and shipping?
- A. Nucleus
- B. Golgi Apparatus
- C. Endoplasmic Reticulum
- D. Ribosomes
Correct answer: B
Rationale: The Golgi Apparatus is the correct answer. It is responsible for packaging, processing, and shipping proteins and lipids within the cell. The nucleus houses genetic material, the endoplasmic reticulum is involved in protein synthesis and lipid metabolism, and ribosomes are responsible for protein synthesis. Therefore, choices A, C, and D are not the correct answers for the functions of packaging, processing, and shipping.
5. Huntington’s disease is carried on the dominant allele. In a situation where two heterozygous parents have the disease, what percentage of their offspring are predicted to be disease-free?
- A. 0%
- B. 25%
- C. 50%
- D. 100%
Correct answer: B
Rationale: In this scenario, both parents are heterozygous for Huntington's disease, meaning each carries one dominant allele (representing the disease) and one recessive allele (representing no disease). When they have offspring, there is a 25% chance that each child will inherit two recessive alleles, making them disease-free. The Punnett square for two heterozygous parents (Hh x Hh) yields a 25% probability of offspring being homozygous recessive (hh) and therefore disease-free. Choice A (0%) is incorrect because there is a possibility of disease-free offspring. Choice C (50%) is incorrect as it represents the likelihood of being a carrier. Choice D (100%) is incorrect as all offspring will not be disease-free in this scenario.
Similar Questions
Access More Features
HESI A2 Basic
$49/ 30 days
- 3,000 Questions with answers
- 30 days access
HESI A2 Premium
$99/ 90 days
- Actual HESI A2 Questions
- 3,000 questions with answers
- 90 days access