PHSC 208, L31

more Carbons is ______ melting point

higher

unsaturated fatty acids are _____ at room temperature

liquid

12:0

Lauric acid

14:0

Myristic acid

16:0

palmitic acid

16:1n-7

palmitoleic acid

18:0

stearic acid

18:1n-9

oleic acid

18:2n-6

linoleic acid

18:3n-3

alpha-Linolenic acid

18:3n-6

gamma-Linolenic acid

20:0

arachidic acid

20:4n-6

Arachidonic acid

20:5n-3

EPA

iClicker: Rank the following fatty acids from highest to lowest

1. 18:1 Oleic

2. 20:0 Arachidic

3. 18:2 linoleic

4. 18:0 stearic

5. 16:0 Palmitic

2 > 4 > 5 > 1 > 3

most naturally occuring unsaturated fatty acids have ___ double bonds

cis

• cause a 30 degree bend in the carbon chain

unsaturated fatty acids have ____ melting points

low

What are some essential fatty acids?

omega-3 and omega-6

• must be obtained from the diet

What are triglycerols?

the primary component of fats and oils in plants and animals

Triglycerols are _____ in water

insoluble

• hydrophobic

• good for thermal insulation. and storing energy

What are phospholipids?

primary component of membrane bilayer

• has hydrophilic polar head group and hydrophobic tail to create a barrier between cell and external environment

Cardiolipin

• R groups primarily unsaturated fatty acids

• negative charges

Phosphatidic acid

-H

Phosphatidylethanolamine

NH3⁺

Phosphatidylcholine (Lecithin)

lowkey has a n*zi symbol

Phosphatidylinositol

ring shape

Phosphatidylglycerol

Phospholipases hydrolyze phospholipids

• phosopholipases cleave

  • a1- first carbon

  • a2- second carbon

  • C+D- third carbon

Sphingolipids are made of ______

sphingosine- amino alcohol backbone

• fatty acid is linked to sphingosine by an amide bond

Cerebroside

head group is a single sugar

sulfatide

sulfuric acid group on the sugar

Tay-Sachs disease

• most common sphingolipid storage disease

• deficiency of Beta-hexosaminidase A enzyme

• accumulation of G_M2

• fatal for children

Cholesterol

• most abundant steroid in animals

• subclassified as sterol because of C3-OH group

• precursor in biosythesis of steroid hormones, vitamin D, bile acids

Cortisol

stress signaling, from adrenal gland

Testosterone

anabolic steroids released from sex glands

Beta- Estradiol

anabolic steroids released from sex glands

Aldosterone

sodium potassium regulation, water level regulation in blood

Vitamin D synthesis

• UV radiation opens up 9-10 Carbon spontaneously

• opened ring makes C=CH2 bond

• more info needed

What is the function of hydroxylated Vitamin D?

promotes and regulations Calcium homeostasis

Naturally occurring isoprenoids have ____carbon structural units

5

Vitamin E function

prevents oxidative damage to membranes

iClicker: While fatty acids are most often formed by the condensation of ___-carbon units, isoprenoids are assembled from ___-carbon units

a. 5, 3

b. 4, 2

c. 2, 3

d. 2, 5

e. 3, 4

d. 2, 5

Eicosanoids are generated from ________

fatty acids

Eicosanoids functions

• inflammation

• platelet aggregation, blood coagulation

How do proteins move around in the fluid mosaic model in the plasma membrane

• dynamic and float around

• moves transversely easily

Fluid Mosaic Model

• label 2 different cells with green or red marker

• fused together by Sedai virus and forms a hybrid cell

• after fusion, mouse and human proteins segregated

• after 40 min at 37 C, green and red intermixed

proves the proteins in bilayer are just moving around

FRAP (fluorescent recovering after photobleaching)

• protein in membrane is marked in green

• hit with high energy, gets rid of fluorescent

• microscope monitors how it goes from no fluorescent to fluorescent (recovery)

How do bilayers form?

• lipids spontaneously be around themselves in aqueous environments (be around themselves)

Bilayer formation driven by _________

hydrophobic effect and van der waals envelope of what phospholipids look like

How does dynamic structure affect the bilayer?

• lets cells and subcellular structures adjust shape and change position

• proteins and lipids diffuse into membrane (fluid mosaic model)