Cell Membrane

Question 1

“inside” the outer cell membrane

Answer 1

layer of phospholipd
cholesterol
sphingomyelin
phosphatidylcoline

Question 2

“inside” the inner cell membrane consists of

Answer 2

phosphatidylETHANOLamine
phosphatidylSERINE (- charged)
phosphatidylLINositol  (- charged, important in cell signaling)

Question 3

Glycolipids are only found in the ____ of the cell membrane

Answer 3

outer

Question 4

Membrane fluidity is moderated by

Answer 4

cholesterol

Question 5

outside of cell membrane: name half a dozen components

Answer 5

cholesterol, glycoproteins, sphingomyolin, “lipid rafts” consisting of sphingomyolin+glycolipids, glycocalyx (NOT INTEGRAL)

Question 6

Which part of the membrane is not integral?

Answer 6

the glycocalyx

Question 7

Transmembrane basics: domains and amino acid constitution

Answer 7

must have at least one two hydrophilic and one hydrophobic domains

membrane spanning portions usually alpha helices with 20-25 hydrophobic proteins

Examples given were band 3, a bicarbonate/chloride ion transporter and Glycophorin

Question 8

Single pass transmembrane versus double pass transmembrane proteins

Answer 8

DP has at least two hydrophobic domains and is usually activated by phosphorylation

examples were g protein linked receptors and porin

Question 9

molecules that can pass through the cell membrane via diffusion include

Answer 9

oxygen, nitrogen

small charged particles like water and co2

small hydrophobic molecules like benzene

Question 10

What kind mode of transport do carbohydrates, amino acids, and charged molecules and ions need to pass through the membrane?

Answer 10

typically facilitated