Membranes & Transport

Question 1

Which membrane lipid is always present in the inner sheet?

Answer 1

Phosphatidylserine

**marker for apoptosis when found in outer leaflet

Question 2

Functions of Glycocalyx

Answer 2

Protection
Cell Adhesion
Cell Identification

Question 3

Erythroblastosis fetalis

Answer 3

Mother has - Rh factor, fetus has + Rh factor, mother starts making antibodies against fetus, really affects subsequent pregnancies bc more antibodies are made

Question 4

Effect of saturated fatty acids on membrane

Answer 4

decreased fluidity (linear molecules that dont allow for flexibility)

Question 5

effect of unsaturated fatty acids on membrane

Answer 5

increased fluidity due to branches and kinks that allow for rotating

Question 6

spur cell anemia

Answer 6

type of hemolytic anemia where there is extra cholesterol in RBCs that decreases fluidity and cause the RBS to break

Question 7

Mimantine/Namenda

Answer 7

antagonist of glutamate receptor (helps treat alzheimer’s as a ligand gated channel)

Question 8

primary active transport

Answer 8

use ATP directly
ex: P type ATPAses (does phosphorylate transporter on aspartate residue) , ABC transporters (doesn’t phosphorylate transporter but ATP is used)

Question 9

secondary active transport

Answer 9

uses energy stored in a concentration gradient

Question 10

sodium glucose transporter (SGLT 1)

Answer 10

unidirectional movment of Na+ and glucose across small intestine and renal tubes
Na+: down concentration –> energy –> glucose: up gradient

**reset by Na+/K+/ATPases

Question 11

Na+/Ca2+ Exchanger (NCX)

Answer 11

antiporter that imports 3Na+ down gradient and 1Ca2+ against

Question 12

Cardiotonic Drugs

Answer 12

cardiac glycosides used –> inhibit the Na+/K+/ATPase–> sodium/potassium gradient collapses–> Na+/Ca2+ gradient is inhibited–> more calcium in heart cells –> trigger muscle contraction–> heart is jumpstarted