Topic 3

Question 1

The ____ surrounds the cytoplasm within cells, which in eukaryotes is filled with membrane-bound organelles.

Answer 1

cell or plasma membrane

Question 2

All cellular membranes are composed of two layers of phospholipids embedded with ___ and ____.

Answer 2

proteins and glycoproteins

Question 3

A bilayer membrane structure was predicted by Gorter and Grendel as early as 1925. They knew that red blood cells (erythrocytes) have _____, and thus have only a _____. They also knew that a major chemical component of these membranes were ____, specifically _____.

Answer 3

no nucleus or other organelles; plasma membrane; lipids; phospholipids

Question 4

Molecules with hydrophilic and hydrophobic domains are called ____.

Answer 4

amphipathic

Question 5

J.D. Robertson first observed membranes in the transmission electron microscope at high power some decades later, revealing them to have a _____.

Answer 5

trilamellar structure

Question 6

____ are proteins bound to the surface of membranes.

Answer 6

peripheral membranes

Question 7

____ proteins that span across the membrane.

Answer 7

integral membrane proteins