lipids Flashcards
3 types of lipids
triglycerides, phospholipids, sterols
what does a triglyceride do
provide energy (9 kcal per gram) and insulation
what does a phospholipid do?
help make the plasma membrane of the cell which helps maintain the cells internal environment
what do sterols do?
(cholesterol) make plasma membrane, make bile (needed to digest fat), emulsify fat
characteristics of lipids
nonpolar and water-hating (hydrophobic)
what is a triglyceride made of
3 fatty acids and a monoglyceride
what does it mean for a fatty acid to be essential?
our body cannot produce them and we must consume them
why can’t our body produce the essential fatty acids?
we can’t place a double bond before the 9th carbon, so we have to consume the ones with a bond at 3 and 6
what do essential fatty acids do
function in growth and clot formation
what state is unsaturated and saturated in at room temp
unsaturated: liquid
saturated: solid
which type of fat is worse for you and why?
saturated is worse because it can cause clotting in the blood and get stuck while traveling in the bloodstream
2 examples of fatty acids
omega 3 and omega 6
2 widely used omega 3 fats
epa and dha
basic composition of a fatty acid
one glycerol, 2 fatty acids, and a polar head made of choline and phosphate
what type of molecule is a phospholipid?
amphipathic; nonpolar/hydrophobic tail and polar/hydrophilic head
source of phospholipids
egg yolk
functions of phospholipids
they make the cell membrane, the hydrophilic heads on the outside and hydrophobic tails on the inside which protects the cell membrane from the water filled outside
how are lipids digested
a combination of mechanical and chemical digestion
what happens in the mouth to digest lipids
salivary glands produce lingual lipase that digest fat a little bit, but are not essential to the process
what do the gallbladder and liver release to aid in the digestion of lipids
bile to emulsify the fat
what is bile made of
mostly water, some cholesterol, salt and monoglycerides
what does bile do?
takes large chunks of fat and separates them (it’s difficult to break their aggregation in a water environment because they are hydrophobic and clump together tightly)
what does the stomach do to digest lipids
nothing
what happens to lipids in the small intestine
they are digested and repackaged as chylomicrons
