Principle:

The process includes:

1. Cell Lysis: Crushing the banana breaks open its cells.

2. Membrane Disruption: A solution containing soap and salt is added. The soap dissolves cell membranes, releasing DNA, while the salt helps the DNA strands come together.

3. Filtration: The mixture is filtered to remove large particles, leaving a solution with DNA.

4. DNA Precipitation: Cold alcohol is added to the filtered solution. DNA is not soluble in alcohol, so it precipitates, becoming visible as a white, stringy substance.

Procedure:

1. **Prepare the Banana Mixture:**

• Peel and mash a ripe banana thoroughly.
• In a cup, mix 1 teaspoon of clear liquid soap and 1/4 teaspoon of table salt with 2 tablespoons of distilled water. Stir gently to avoid foam.
• Add 2 tablespoons of the mashed banana to the soap solution. Stir the mixture gently for about 10 minutes.

2. **Filter the Mixture:**

• Place a coffee filter over a clean cup and pour the banana mixture into it. Allow the liquid to pass through, collecting the filtrate in the cup. This may take several minutes.

3. **Extract the DNA:**

• Obtain a test tube containing cold isopropyl alcohol (chilled by placing in ice water).
• Carefully add the filtered banana solution to the test tube with cold alcohol.
• Let the test tube sit undisturbed for about 4 minutes. DNA will precipitate out as a white, stringy substance.
• Use a thin glass rod or a plastic pipette to gently spool or collect the DNA.

This method allows you to see the DNA that is present in the cells of the banana.

For a visual demonstration, you can watch the following video:



Start Date:

End Date:

Calculate Duration

const form = document.getElementById('duration-calculator'); const result = document.getElementById('result');

form.addEventListener('submit', (event) => { event.preventDefault();

const startDate = new Date(document.getElementById('start-date').value); const endDate = new Date(document.getElementById('end-date').value);

let years = endDate.getFullYear() - startDate.getFullYear(); let months = endDate.getMonth() - startDate.getMonth(); let days = endDate.getDate() - startDate.getDate();

if (days < 0) { const monthDays = new Date(endDate.getFullYear(), endDate.getMonth(), 0).getDate(); days += monthDays; months--; } if (months < 0) { months += 12; years--; } result.textContent = `Duration: ${years} years, ${months} months, ${days} days`; });