Membranes I- Lecture 8/19/21

Question 1

Membrane structure

Answer 1

Lipid bilateral with polar head and lipid tail, discovered by TEM

Question 2

Carbohydrates

Answer 2

Regulate structure and function of the plasma membrane

Question 3

Makeup of the membrane

Answer 3

Generally close to 50-50 lipids. To proteins, though specialized cells can have different makeups

Question 4

Fluid mosaic model

Answer 4

Bilateral behaves as a fluid, with proteins moving within

Question 5

Phospholipids

Answer 5

One of the most commonly incorporated in the cell, distributed asymmetrically one saturated chain one unsaturated

Question 6

Sphingolipids

Answer 6

Most common in cell, has two saturated tails

Question 7

Lysosomal storage diseases

Answer 7

Diseases that result in a deficiency in an enzyme involved in sphingolipid metabolism, include Tay-Sachs and Fabrys disease

Question 8

Enzyme replacement therapy

Answer 8

Used to treat LSDs, has been highly effective for Fabrys and Gaucher’s disease

Question 9

Increases membrane fluidity

Answer 9

Heat, Double bonds, short Acyl change, low cholesterol content (at body temp)

Question 10

Decreases membrane fluidity

Answer 10

Codl, more sturation, long acyl chains, high cholesterol content

Question 11

walking “mycoplasma” pneumonia

Answer 11

hang out at the base of cilia and ‘suck” cholesterol out, making them too limp to beat

Question 12

Lipid rafts

Answer 12

Specialized cholesterol and sphingolipid rich microenvironments that move rapidly within a leaflet. Works for signal transduction, endocytosism and rapid reorganization of the membrane for motility

Question 13

Transmembrane proteins

Answer 13

Have a large hydrophobic intramembrane segments, takes 20-25 aa to span

Question 14

Glycoprotein function

Answer 14

1. blood type antigens
2. Pathogen recognition sites
3. Reservoir for cytokines/GFs

Question 15

Taxoplasmosis

Answer 15

Toxoplasma gondii is an example, recognizes specific glycoproteins to invade cells

Question 16

Eicosanoids

Answer 16

Lipid component of plasma membranes that have important functions

Question 17

PGE2

Answer 17

Prostaglandin, responsible for vasodilation, inducing uterine contractions

Question 18

TXA2

Answer 18

Thromboxanes, induces vasocontriction and platelet aggragation

Question 19

LTC4, LTD4, LTE4

Answer 19

Leuktrienes, induce vasodilation and bronchodilation. Overproduction can lead to asthmatic attack