Question

The mass ratio of proteins vs lipids varies depending on the function and location of the membrane. Where might you find a membrane containing about 75% protein and 25% lipids? (hint: one place at least is an organelle) How about ~50% protein and 50% lipids? How about a membraneLess than 25% protein? (Hint: in somewhere in the brain)

Answer 1

Ans). The amount of protein present on membrane is highly variable depending on the function of the membrane. In inner membrane of mitochondria, the amount of protein content is 75% and lipid is 25% due to abundance of proteins involved in electron transport and oxidative phosphorylation. Similarly, the inner membrane of chloroplast also contain same protortion of protein:lipid (75:25). Whease plasma membrane contains 50:50 protein and lipid membrane. On the other hand the myelin membrane, which act as electrical insulation for nerve cell axons, constitute less than 25% protein and 75% lipid.