1. What is Copy Number Calculation?

The copy number calculation determines how many copies of a DNA molecule exist per cell based on the total DNA concentration, molecular weight, and number of cells. This is important in molecular biology and genetics research.

2. How Does the Calculator Work?

The calculator uses the copy number formula:

Where:

• \( CN \) — Copy number per cell (dimensionless)
• \( C \) — DNA concentration (g)
• \( N_A \) — Avogadro's number (6.022 × 10²³ /mol)
• \( MW \) — Molecular weight (g/mol)
• \( N_C \) — Number of cells (dimensionless)

Explanation: The equation converts mass concentration to molar quantity using Avogadro's number, then distributes this quantity across the specified number of cells.

3. Importance of Copy Number Calculation

Details: Knowing copy number is essential for gene dosage studies, plasmid copy number determination, and ensuring consistent experimental conditions in molecular biology.

4. Using the Calculator

Tips: Enter DNA concentration in grams, molecular weight in g/mol, and number of cells. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is Avogadro's number?
A: Avogadro's number (6.022 × 10²³) is the number of particles (atoms, molecules) in one mole of substance.

Q2: How do I determine molecular weight?
A: Molecular weight can be calculated from the sequence (for DNA: 660 g/mol per base pair) or measured experimentally.

Q3: What are typical copy number values?
A: In bacteria, plasmids range from 1-100 copies/cell. For genomic DNA, it depends on ploidy (e.g., 2 copies/diploid cell).

Q4: Does this work for RNA too?
A: Yes, the same calculation applies for RNA molecules when you use the appropriate molecular weight.

Q5: How accurate is this calculation?
A: Accuracy depends on precise measurement of concentration and molecular weight. It assumes uniform distribution across cells.