Prepare and present a report of a biological investigation on (food nutrients in various food samples, transportation of materials in flowering plants, pulse rate in human, aerobic and anaerobic respiration)

1. Choose a Research Question

Select a specific question you want to answer. For example:

• Which food sample contains the most starch?
• How does exercise affect human pulse rate?

2. Form a Hypothesis

A hypothesis is an educated guess about what you think will happen. Write it as a statement. Example: "I think that rice will contain more starch than cassava."

3. List Materials and Equipment

Write down everything you need for the investigation. Be specific.

4. Describe the Procedure

Explain each step clearly so someone else could repeat your experiment. Use numbered steps.

5. Collect Your Data

Record your observations and measurements in a table. Include units (for example, grams, beats per minute, seconds).

6. Analyze Your Data

Look at your data and identify patterns. You may need to calculate averages or percentages.

7. Draw Conclusions

Explain whether your data supports your hypothesis or not. Suggest possible reasons for your findings.

8. Suggest Improvements

Mention what you would do differently to improve the investigation.

When you present your report, follow this structure:

• Title – Clear and specific
• Aim – What you wanted to find out
• Hypothesis – Your prediction
• Materials – What you used
• Procedure – How you carried out the investigation
• Results – Data in tables and possibly charts
• Discussion – What the results mean
• Conclusion – Summary of findings
• Recommendations – How to improve or extend the work

Speak clearly when presenting. Point to your results table or chart. Make eye contact with your audience.

Aim: To find out which food sample (rice, cassava, banana, or bread) contains starch.

Hypothesis: I think that rice contains the most starch.

Materials:

• Iodine solution
• Dropper
• White tile
• Small pieces of rice, cassava, banana, and bread

Procedure:

1. Place a white tile on the table.
2. Put small pieces of each food sample on the tile, leaving space between them.
3. Add a few drops of iodine solution to each food piece.
4. Observe and record any colour change immediately.
5. A blue-black colour indicates the presence of starch.

Results:

Analysis: Two samples (rice and bread) gave a blue-black colour, meaning they contain starch. Two samples (cassava and banana) did not change colour, so they do not contain starch.

Conclusion: My hypothesis is partially correct. Rice contains starch, but I did not expect bread to also contain starch. Both rice and bread are starchy foods that people eat for energy.

Presentation tip: When presenting, hold up the white tile or show a photo of your results so classmates can see the colour changes clearly.

In Tanzania, biological investigation skills are useful when testing food quality. For example, a small food vendor at a market in Dar es Salaam can use a simple iodine test to check if the cassava flour they are buying has been properly processed — poorly processed cassava may still contain starch that can release cyanide. This simple test helps protect people's health and ensures they sell safe food to their customers.