Question

Membranes are important structural features of cells.

1. Describe how membrane structure is related to the transport of materials across the membrane.
2. Describe the role of membranes in the synthesis of ATP in either cellular respiration or photosynthesis.

Answer 1

a) The membrane structure plays an important role in the transportation of materials across the membrane. The cell membrane is made up of phospholipids that have hydrophobic tails and hydrophilic heads. The proteins have hydrophobic and hydrophilic regions that determine if they get embedded into the membrane. From there, the proteins can allow certain materials to exit and enter the cell. There are specific types of transport proteins that allow specific materials to cross. For example, channel proteins have a hydrophilic channel that allows most molecules or ions to pass through. Anther type of protein is the carrier protein. They attach or hold onto their “passengers” and change its shape together to get through the membrane.

b) In the inner membrane of the mitochondrion, there is an electron transport chain. The membrane increases the surface area so a lot more copies of the chain can exist. Within the mitochondrion, there are ATP synthase that makes ATP out of ADP and inorganic phosphate. The ATP synthase is located inside the chloroplast for photosynthesis.