Membrane Structure

What type of molecule makes up the bilayer in the structure of the plasma membrane?

• Phospholipid

• DNA

• RNA

• Integral protein

Which molecule is amphipathic?

• Peripheral protein

• Hydrocarbon tail

• Phosphate head

• Integral protein

Which elements are found in the head of a phospholipid bilayer?

• C, H, O, N

• C, H, O, P

• C, P, N, O

• P, N, O

State the two Scientists who concluded that the cell membrane formed a bilayer?

• Davson and Danieli

• Gorter and Grendel

• Singer and Nicolson

• Watson and Crick

Which is an essential feature of the Davson–Danielli model of membrane structure?

• A phospholipid monolayer with intrinsic and extrinsic proteins

• A layer of protein sandwiched between two layers of lipid

• A phospholipid bilayer with intrinsic and extrinsic proteins

• A layer of lipid sandwiched between two layers of protein

Which evidence falsifies the Davson–Danielli model?

I. The presence of globular proteins within the phospholipid bilayer

II. Non-polar amino acids cause proteins to remain embedded in membranes

III. Membrane proteins remain in a fixed position inside a membrane

• I only

• I and II only

• II and III only

• I, II and III

What simple molecules join to form a protein?

• Fatty acids and phosphate

• Fatty acids and glycerol

• Amino acids

• Alpha glucose

What is a role of cholesterol in animal cells?

• It increases body fat

• It controls membrane fluidity

• It lines the inner wall of capillaries

• It is a constituent of bile

Which one is not a role of a membrane protein?

• Hormone binding sites

• Cell adhesion

• Cell-to-cell communication

• Enzymes

Tick which one(s) are functions of membrane proteins?

• Channels for facilitated diffusion

• Pumps for active transport

• Binding sites for insulin

• Forming tight junctions for cell adhesion