What are the key structural differences between plant and animal cells?

The key structural differences between plant and animal cells include:

• Cell Wall: Plant cells possess a rigid cell wall outside the cell membrane, providing structural support and protection, which is absent in animal cells.
• Chloroplasts: Plant cells contain chloroplasts for photosynthesis, while animal cells do not.
• Vacuole: Plant cells typically have a large, central vacuole that stores water, nutrients, and waste, and helps maintain turgor pressure. Animal cells may have small, temporary vacuoles, but not a large central one.
• Centrioles: Animal cells have centrioles, which are involved in cell division, whereas most plant cells lack them.
• Shape: Plant cells often have a fixed, rectangular shape due to the cell wall, while animal cells tend to be more rounded and irregular.

The function of methylene blue in the experiment is to act as a stain. It is a basic dye that binds to negatively charged components within the cell, such as the nucleus and certain parts of the cytoplasm. This increases the contrast between the cell structures and the surrounding background, making them more visible and easier to observe under the microscope.

A cover slip is placed over the specimen for several reasons:

• It protects the specimen from drying out, keeping it hydrated for observation.
• It flattens the specimen, ensuring a uniform thickness for better viewing under the microscope.
• It protects the objective lens of the microscope from coming into direct contact with the specimen or the liquid on the slide.
• It holds the specimen in place, preventing it from moving.
• It helps to prevent the formation of air bubbles when properly applied, which can obstruct the view.