### 1. Question
What role do microRNAs play in the regulation of gene expression in eukaryotic cells?

A) MicroRNAs increase the stability of mRNA molecules, enhancing gene expression.

B) MicroRNAs bind to mRNA molecules, leading to their degradation or inhibition of translation, thereby reducing gene expression.

C) MicroRNAs bind to DNA, promoting gene transcription.

D) MicroRNAs have no significant impact on gene expression.

### 2. Question
Which process is responsible for the majority of ATP production in cellular respiration?

A) Glycolysis

B) The Citric Acid Cycle (Krebs Cycle)

C) Oxidative Phosphorylation

D) Fermentation

### 3. Question
How does the CRISPR-Cas9 system enable precise genome editing?

A) CRISPR-Cas9 uses RNA templates to replace defective DNA sequences with correct ones.

B) CRISPR-Cas9 cuts DNA at specific locations determined by a guide RNA, allowing for targeted modifications.

C) CRISPR-Cas9 induces random mutations in the genome, which are then selected for beneficial traits.

D) CRISPR-Cas9 inhibits gene expression without altering the DNA sequence.

### 4. Question
What is the primary function of telomeres in eukaryotic chromosomes?

A) To facilitate chromosome replication by providing a starting point for DNA polymerase.

B) To protect the ends of chromosomes from degradation and prevent them from fusing with other chromosomes.

C) To enhance the efficiency of DNA repair mechanisms.

D) To regulate gene expression by binding transcription factors.

### 5. Question
Which of the following best describes the concept of symbiosis in an ecological context?

A) A relationship where one organism benefits at the expense of another.

B) A relationship where both organisms involved benefit from the interaction.

C) A relationship where organisms compete for the same resources​