Question

A student proposes six models of a hypothetical plasma membrane (figure 1). Identify the model that best represents the plasma membrane of a hypothetical cell that exists in a non-aqueous environment and whose cytosol is similar to that of an animal cell. Provide TWO pieces of reasoning to support your identification

Answer 1

Answer:

The model that best describes the plasma membrane of the hypothetical cell is E

Explanation:

The model that best represents the plasma membrane of a hypothetical cell that exists in a non-aqueous environment and whose cytosol is similar to that of an animal cell is E

The reasons behind the answer are

1) The cytosol of an animal cell is an aqueous solution that surrounds the internal organelles attached to the cytoplasm. Since the model describes the cytosol to be similar to that of an animal cell, then the cytosol will be aqueous cytosol.

2) The plasma membrane of a cell in an aqueous environment is made up of phospholipid bilayer (where the head/phosphate group is hydrophilic and the tail/lipid is hydrophobic) in which the head of each lipid layer is oriented inwards while the tails are oriented outward. This allows for molecules that are hydrophobic to easily pass through the membrane since they are like the inward hydrophobic tails while hydrophilic molecules cannot pass easily except by activated carriers. However, if the cell is in a non-aqueous environment, there might not be a bilayer as the lipid/hydrophobic tail does not interact with water or another hydrophilic head because of the absence of bond to hold it together. This thus causes the head to interact with the aqueous solution inside the cell and the tail interact with the non aqueous environment outside the cell while each part of the phospholipid regulating what goes in/out of the cell individually.