quiz 5 prep Flashcards
simple lipids are glycerides also called ____
acylglycerols
glycerides are made up of ____
esters of glycerol and 1, 2, or 3 fatty acids
_____ are the main component of fats and oils
glycerides
saponification is
hydrolysis of triglycerides with alkali (NaOH, KOH)
saponification forms ____+_____
glycerin + salts of fatty acids
salts of fatty acids =
soap
____ soap is made from tallow/lard
lye
saponification number is equivalent to
the amount of alkali needed to completely saponify 100g of fat/oil
an increase in the saponification number = a decrease in ____
the average fatty length
Iodination: ____ fatty acids readily bond to iodine with ___ iodine atoms at each end
unsaturated; 2
Hydrogenation is ___
adding H to unsaturated fatty acids
hydrogenation converts ___ to ___ and removes ____
double bonds to single bonds; “kinks”
What does hydrogenation do to vegetable oils?
it solidifies them
think margarine/shortening
hydrogenation can convert ___ double bonds to ___
cis; trans
are there health concerns associated with chemically hydrogenated “trans fat”
yes; increased serum cholesterol; heart disease, diabetes, etc.
oxidation (“____”) is the formation of ____
Rancidity; free radicals
what do free radicals break?
C-C bonds of fatty acids
oxidation causes a disagreeable _____ such as in ____
odor/flavor; blue cheese
oxidation helps the addition of antioxidants such as
Se, Vit E, Vit C, betacarotene, ethoxyquin, BHA, BHT
another simple wax is ___ which has minor importance in nutrition, a low digestibility, and greater commercial value
waxes
___+___+___= compound lipids
fatty acids
alcohol
nonlipid
what are phospholipids?
- white waxy solids that turn brown when exposed to air
* constituents of biological membranes
what composes a phospholipid?
- glycerol (or other alcohol) backbone
- at least one fatty acid
- phosphoric acid
- nitrogenous base (usually choline, ethanol amine, serine)
What is amphipathic organization?
It contains both hydrophilic and hydrophobic portions in the same molecule
- hydrophilic: water soluble such as phosphoric acid, amino acid groups
- hydrophobic: lipid soluble such as fatty acid tails
lecithin (phosphatidylcholine) = ___+___+___+___
glycerol + 2fatty acids + phosphoric acid + choline
Lecithin in foods acts as
1, natural emulsifier
- carrier for micronutrients
- use in cosmetics
cephalin (phoshatidylethanolamine) is
white matter of brain and spinal cord
similar to lecithin, with ethanol amine instead of choline
sphingomyelin is
a component of nervous tissue (myelin sheath)
uses sphingosine instead of glycerol
glycolipids = ___+___+___
glycerol
2 fatty acids
sugar residue
up to 60% of the lipid in forages can be ____ (in chloroplasts), a glycolipid
galactolipid
glycolipids in animals compose:
- myelin sheath (cerebrosides)
2. brain tissue (gangliosides)
glycolipids determine____
blood type
glycolipids determine blood type from ___
CHO on surface of red blood cells
lipoproteins transport ____
molecules for lipids in blod (fatty acids and cholesterol)
lipoproteins are synthesized in ___
the small intestine during absorption (chylomicron)
chylomicrons are repackaged in ___
the liver
LDL stands for _____. Transports to ___ and is considered ___ cholesterol
Low Density Lipoprotein
peripheral cells
bad cholesterol
HDL stands for ____. Transports to _____ and is considered ____ cholesterol
High Density Lipoprotein
back to the liver
good cholesterol
Derived lipids include:
- sterols
- steroid hormones
- ProVitamin D
- Bile acids
- Prostaglandins
____ is the parent molecule of sterols
cholesterol
Steroid hormones include:
- testosterone, estrogen, progesterone
- cortisol (stress hormone)
- Aldosterone (kidneys)
bile acids conjugated to glycine and taurine are
glycocholic acid and taurocholic acid
prostaglandins are derivatives of
arachidonic acid
Prostaglandins stimulate ____ and contribute to
smooth muscle contractions; inflammatory response, regulation of blood pressure, fever, reproduction (ovulation, menstruations, parturition)
NSAIDS are _____ such as
non-steroidal anti-inflammatory drugs; aspirin, ibuprofen, naproxen
How do NSAIDS work?
they block synthesis of prostaglandins from arachidonic acid which inhibits cyclooxygenase (COX) enzymes
What lipolytic enzymes come from the mouth?
NONE
Presence of ____ (distension) in stomach causes the release of the hormone ___ by ____
food; Gastrin: pylorus
Gastrin stimulates overall gastric secretion:
Mucous, HCl, Pepsin, GASTRIC LIPASE
Gastric Lipase comes from ____ and hydrolyzes ___ into ____
chief cells; triglycerides into monoglyceride and 2 free fatty acids
gastric lipase in the adult stomach is ____by the low pH but is ____ in the small intestine
denatured; reactivated
gastric lipase plays a bigger role in ____
milk fed animals
____ from the crypts of lieberkuhn, is triggered by the presence of ____ and stimulates ____ to release___
secretin; gastric acid (HCl); pancreas; bicarbonate buffers
____ from the crypts of lieberkuhn is triggered by ____ and stimulates___ to release____
Cholecystokinin; the presence of lipid/peptides; pancreas; digestive enzymes
_____ is similar but more potent than gastric lipase
pancreatic lipase
pancreatic lipase hydrolyzes ___ to ____+____
triglycerides; monoglyceride and 2 free fatty acids
_____ removes fatty acid esterified to cholesterol
cholesterol esterase
_____ hydrolyzes lecithin and other phospholipids
phospholipase
CCK stimulates ____ for bile release into duodenum
contraction of the gall bladder
____ comes from the liver and gall bladder
bile
Bile aids in the emulsification of lipids, acts as _____ and helps the formation of ____ for increased surface area for lipase action
a detergent; micelles
Absorption of mixed micelles contents uses ____ into the enterocyte
passive diffusion
Mixed micelle contents undergo ___ into triglycerides inside the enterocyte and ____(lipoproteins) are formed in the endoplasmic reticulum
re-esterification; chylomicrons
Chylomicrons are expelled from the enterocyte via ___ into ____ in mammals and ____ in birds.
exocytosis; lacteal; blood capillaries
chylomicron are transported in lymph to the liver and other peripheral tissues for ____ into other lipoproteins
repackaging
