HESI A2
Biology
EXAM READINESS GUIDE
Q&S
©2024/2025
,1. Which of the following cellular organelles is primarily
responsible for protein synthesis?
- A) Mitochondria
- B) Ribosome
- C) Golgi apparatus
- D) Lysosome
Answer: B) Ribosome
Rationale: Ribosomes are the cellular structures where
protein synthesis occurs. They translate mRNA into
polypeptide chains.
2. What phase of the cell cycle does DNA replication
occur?
- A) G1 phase
- B) S phase
- C) G2 phase
- D) M phase
Answer: B) S phase
Rationale: During the S (synthesis) phase of the cell
cycle, the cell duplicates its DNA.
3. Which type of bond is formed between the oxygen and
hydrogen atoms within a water molecule?
- A) Ionic bond
- B) Covalent bond
- C) Hydrogen bond
- D) Van der Waals forces
Answer: B) Covalent bond
Rationale: Water molecules are held together by polar
©2024/2025
, covalent bonds between oxygen and hydrogen atoms.
4. In the context of genetic inheritance, which of the
following represents a homozygous recessive genotype?
- A) Aa
- B) aa
- C) AA
- D) AaBb
Answer: B) aa
Rationale: A homozygous recessive genotype consists
of two identical recessive alleles.
5. What is the main function of the smooth endoplasmic
reticulum?
- A) Protein synthesis
- B) Lipid synthesis
- C) DNA replication
- D) ATP production
Answer: B) Lipid synthesis
Rationale: The smooth ER is primarily involved in the
synthesis of lipids and hormones.
### Fill-in-the-Blank
6. The __________ is often referred to as the powerhouse
of the cell because it generates ATP.
Answer: Mitochondria
Rationale: Mitochondria are responsible for producing
ATP through cellular respiration.
©2024/2025
Biology
EXAM READINESS GUIDE
Q&S
©2024/2025
,1. Which of the following cellular organelles is primarily
responsible for protein synthesis?
- A) Mitochondria
- B) Ribosome
- C) Golgi apparatus
- D) Lysosome
Answer: B) Ribosome
Rationale: Ribosomes are the cellular structures where
protein synthesis occurs. They translate mRNA into
polypeptide chains.
2. What phase of the cell cycle does DNA replication
occur?
- A) G1 phase
- B) S phase
- C) G2 phase
- D) M phase
Answer: B) S phase
Rationale: During the S (synthesis) phase of the cell
cycle, the cell duplicates its DNA.
3. Which type of bond is formed between the oxygen and
hydrogen atoms within a water molecule?
- A) Ionic bond
- B) Covalent bond
- C) Hydrogen bond
- D) Van der Waals forces
Answer: B) Covalent bond
Rationale: Water molecules are held together by polar
©2024/2025
, covalent bonds between oxygen and hydrogen atoms.
4. In the context of genetic inheritance, which of the
following represents a homozygous recessive genotype?
- A) Aa
- B) aa
- C) AA
- D) AaBb
Answer: B) aa
Rationale: A homozygous recessive genotype consists
of two identical recessive alleles.
5. What is the main function of the smooth endoplasmic
reticulum?
- A) Protein synthesis
- B) Lipid synthesis
- C) DNA replication
- D) ATP production
Answer: B) Lipid synthesis
Rationale: The smooth ER is primarily involved in the
synthesis of lipids and hormones.
### Fill-in-the-Blank
6. The __________ is often referred to as the powerhouse
of the cell because it generates ATP.
Answer: Mitochondria
Rationale: Mitochondria are responsible for producing
ATP through cellular respiration.
©2024/2025
