Cell Membrane and Transport Mechanisms

The cell membrane, also known as the plasma membrane, is a biological membrane that separates the interior of all cells from the outside environment. It is selectively permeable, allowing certain substances to pass through while blocking others. A variety of transport mechanisms, including diffusion, osmosis, and active transport, are used by the cell to move substances across the cell membrane. For example, in a laboratory experiment, a cell is placed in a solution of sugar. Over time, the concentration of sugar inside the cell changes.

Describe the following processes:

Describe the process of diffusion and osmosis and how it relates to the cell membrane. Also include if this is a passive or active type of transport.

How is active transport different from passive transport?

In the laboratory experiment mentioned above, the concentration of sugar inside the cell changes over time. Explain how each of the processes - diffusion, osmosis, passive transport, and active transport - could be involved in this change.

Predict what would happen to the cell if it were placed in a solution with a very high concentration of sugar. Consider the processes of diffusion, osmosis, passive transport, and active transport in your response.

Scientists claim that active transport is a crucial process that allows cells to maintain homeostasis, even in environments with fluctuating external concentrations of different substances. Justify this claim using your understanding of active transport and its role in relation to the cell membrane.