A slide of potato cells was viewed using a light microscope - Edexcel - GCSE Biology - Question 3 - 2020 - Paper 1

The correct answer is D: cell wall, chloroplast, large vacuole. These structures are characteristic of plant cells and are absent in animal cells.

First, we need the mean lengths:

• Potato 2 (5 weeks): 64 µm
• Potato 3 (10 weeks): 30 µm

To find the percentage difference:

$\text{Percentage Difference} = \frac{|64 - 30|}{\frac{64 + 30}{2}} \times 100$

Calculating the average length:

$\frac{64 + 30}{2} = \frac{94}{2} = 47$

Then substituting back in:

$\text{Percentage Difference} = \frac{34}{47} \times 100 \approx 72.34\%$

Thus, the percentage difference is approximately 72.34%.

1. Temperature of the storage environment.
2. The type or age of the potato used in the experiment.

Potatoes need glucose for energy and respiration. Glucose is essential for the production of ATP, which powers various cellular processes.

Starch is broken down into glucose through the action of enzymes such as amylase. Amylase catalyzes the hydrolysis of starch, which involves:

1. The starch fitting into the active site of the enzyme.
2. The bonds between glucose molecules in starch being broken down into monomers of glucose. This breakdown process allows the stored starch to be utilized as a source of energy.