Photo AI
Figure 3 shows ciliated epithelial cells from the airways of a human as seen using a light microscope - Edexcel - GCSE Biology Combined Science - Question 2 - 2021 - Paper 1
Question 2
Figure 3 shows ciliated epithelial cells from the airways of a human as seen using a light microscope. (i) Draw the cell labelled A in the box below. Label three pa... show full transcript
Worked Solution & Example Answer:Figure 3 shows ciliated epithelial cells from the airways of a human as seen using a light microscope - Edexcel - GCSE Biology Combined Science - Question 2 - 2021 - Paper 1
Step 1
Draw the cell labelled A in the box below. Label three parts of this cell on your diagram.
Answer
To draw the ciliated epithelial cell:
- Start by sketching the basic shape of the cell, which is typically columnar.
- Add cilia at the top, as they extend outward to help in movement.
- Include the nucleus, typically located centrally, identifying it as a prominent structure.
- Lastly, label the cytoplasm, which fills the interior of the cell.
- Ensure to clearly label all three parts on your diagram.
Step 2
State the function of the ciliated epithelial cells in the airways of the human breathing system.
Answer
Ciliated epithelial cells serve a crucial role in the airways by:
- Moving mucus and trapped particles out of the airways, helping to keep the respiratory system clear of pathogens and debris.
- The coordinated beating of the cilia creates a current, which pushes the mucus upwards towards the throat, facilitating its removal.
Step 3
Use information from Figures 4 and 5 to calculate the mean rate of respiration of the maggots in mm per minute.
Answer
The mean rate of respiration can be calculated using the distance moved by the drop of liquid measured in millimeters and the time taken.
- Measure the distance from the starting point to the new position after ten minutes.
- If, for example, the drop moved 4 cm (or 40 mm), the mean rate of respiration would be:
Step 4
Describe a control for this investigation.
Answer
A suitable control for this investigation would involve setting up a similar experimental setup without maggots. This way, you can determine if any movement of the colored liquid occurs due to factors other than maggot respiration, ensuring that the results are solely due to the activity of the maggots.