Lecture 19.1

What lipid is responsible for protection?

Waxes

What lipid is responsible for energy stores?

Triacylglycerols

What lipid is responsible for membranes?

glycerophosoholipids and steriods (cell structure)

What lipid is responsible for Nerve Insulation?

sphingolipids

What lipid is responsible for hormones?

steriods

What lipid is responsible for Messengers (immunity, inflammation & CNS)?

eicosanoids and glycolipids(nerves)

Characteristics of Saturated Fatty Acids

• no double bonds

• chains packed together as a result of hydrophobic attraction

• solid at room temp (higher melting point)

Characteristics of Unsaturated Fatty Acids

• a long chain of carboxylic acid containing one or more carbon-carbon double bonds

• due to the kinks, chains cant pack together as effectively

• lower melting point, liquid at room temp.

What is a cis unsaturated fatty acid

naturally occurring

Determining Melting Temperature of a Fatty Acid

1) Chain Length: the longer the carbon chain is the higher the melting temp

2) Degree of Saturation: the more double bonds the lower the melting temperature

Characteristics of TAGs

• two types: fat and oil

• non polar, hydrophobic, and not ionic

• animal fat contains more sat fats than plant oils

• because of high degree saturation in animal fat, it is a solid at room temperature

• because of higher content of unsaturated fatty acids in plant oil, it is commonly liquid at room temp

• double bonds in naturally occurring unsaturated fatty acids are always cis in configuration

• neutral charge

• three fatty acid chains

What is the biochemical reaction for TAGS?

main energy storage molecule for animals

What is the hydrolysis reaction for TAGS?

Saponification - process of making soaps

What is the hydrogenation reaction for TAGS?

process of making sat fats from poly unsat fats

Iodine number

the number of grams of iodine which will react with 100g of fat or oil

Trans fatty acid

• increases LDL

• decreases HDL

• do not exit is nature

• can pack as densely as sat fats

Cholesterol

• four fused rings

• our bodied can synthesize cholesterol from Acetyl CoA

• precursor for steroid hormones, Vitamin D and bile

• 50% found in cell membranes

Simple diffusion

small uncharged molecules pass through the lipid bilayer from high gradients to low gradients (CO2 and O2

• passive tranpsort

Facilitated Diffusion

the issue of embedded integral carrier proteins to transfer molecules

• passive transport

• glucose

Sodium Potassium Pump

a protein that has been identified in many cells that maintains the internal concentration of potassium ions [K⁺] higher than that in the surrounding medium (blood, body fluid, water) and maintains the internal concentration of sodium ions [Na⁺] lower than that of the surrounding medium.

• requires energy

• active transport

Characteristics of Prostaglandin

• responsible for some of the pain and swelling of inflammation

• lower blood pressure

• affect blood pressure

• stimulate uterine contractions

• lower gastric secretions

Characteristics of Leukotriene

• trigger allergic reactions

• triggers asthmatic response

• trigger inflammation

what does aspirin do to prostaglandin?

ultilizes irreversible inhibition to block prostaglandin productions