Question

According to unit membrane structure, the thickness of plasma membrane is about ___________.

• A. 35 $\mathring{A}$
• B. 20 $\mathring{A}$
• C. 75 $\mathring{A}$
• D. 100 $\mathring{A}$

Answer 1

The correct option is C 75 $\mathring{A}$

According to Robertson's concept of unit membrane, the cell membrane is trilaminar. It has a thickness of about 75$\mathring{A}$ with a central lipid layer of 35$\mathring{A}$ thick and two peripheral protein layers of 20$\mathring{A}$ each.