Cell Structure and Function

Biochemical investigations revealed that cell membranes contain:

• Only lipids
• Only proteins
• Water channels
• Proteins and carbohydrates

What additional lipid helps modulate membrane fluidity?

• Sphingomyelin
• Glycerol
• Fatty acids
• Cholesterol

The nonpolar tails of phospholipids are located:

• On the surface
• Attached to carbohydrates
• Inside the bilayer
• Bound to ions

The main structural components of the plasma membrane are:

• Nucleic acids and proteins
• Carbohydrates and nucleic acids
• Lipids and proteins
• Proteins and carbohydrates

Which cells were especially useful in early plasma membrane research?

• Bacterial cells
• Plant cells
• Nerve cells
• Human red blood cells