Biochem part 4 Lipids Flashcards
Type of bond that is characteristic of fats
Ester bonds
Fatty acids are composed of a (polar/ nonpolar) hydrocarbon tail and a (polar / non polar) carboxylic acid head
non polar tail
polar head
Unsaturated fatty acids contain double bonds which (increase / decrease) the melting temperature
Decrease the melting temperature
Naturally occurring double bonds exist in the ( cis / trans) configuration
Cis-
Hydrogenation of fatty acids (increases / decreases) the melting point
increases
To generate an unsaturated fat from a saturated fat, it would use a/n (Reduction / Oxidation) reaction
Oxidation
-losing electrons/hydrogens
“OIL”
the 3 essential fatty acids
Linoleic (omega 6)
Linolenic (omega 3)
Arachidonic (omega 6)
the number on the Omega; ex. omega 3, 6, 9 tells you what about the double bond
where the first double bond occurs
t/f Coconut oil is the “most saturated”
true
Which would have a higher chance of going rancid PUFAs or MUFAs
PUFA
the more unsaturated = greater chance of rancid
-more double bonds
of carbons in Lauric acid
12
of carbons in Myristic acid
14
of carbons in Palmitic acid
16
of carbons in Stearic acid
18
of carbons in Oleic, Linoleic, and Linolenic acid
18
- difference is number of double bonds
- 1, 2, 3 double bonds respectively
of carbons in Arachadonic acid
20
4 double bonds
Every 2 carbons in get ____ acetyl-CoA’s
1 acetyl CoA
Phospholipids contain ____#___ fatty acids and a polar head group
2 fatty acids
2 main classes of non glycerol lipids
Sphingolipids
Steroids
The major lipid component of myelin sheath (white matter)
Sphingomyelin
Most abundant sterol in humans
Cholesterol
Cholesterol is derived from ______
Acetyl CoA
-think B5 pantothenic acid
Rate limiting enzyme of cholesterol synthesis
HMG CoA reductase
-inhibited by increased levels of cholesterol
HMG CoA reductase converts HMG CoA —-> ________
mevalonate
Rate limiting enzyme in steroid biosynthesis
Desmolase
- converts cholesterol —> pregnenolone
- pregnenolone —> progesterone
- progesterone —> all other steroid hormones
Rate limiting enzyme of Ketone body synthesis
HMG CoA Synthase
Chylomicrons are produced and secreted by what cells
Intestinal mucosal cells
Chylomicrons are produced in response to the dietary intake of ______
Fats
-fats are absorbed and repackaged as chylomicrons
Where do chylomicrons take triacyglycerides
to peripheral tissues from intestines
VLDLs are synthesized and secreted from the ____
liver
VLDL transport (exogenous/endogenous) triacylglycerides to peripheral tissues
Endogenous TAGs (from liver)
LDL is derived from ____ and transport cholesterol from the liver to peripheral tissues
VLDL
Which contains the greatest amount of cholesterol; VLDL, LDL, HDL, Chylomicrons
LDL
Which Lipoprotein transports cholesterol from peripheral tissues BACK to the liver
HDL
Enzyme required for the uptake of triglycerides that are carried by VLDL and chylomicrons
Lipoprotein lipase
Least dense lipoprotein
Chylomicron
The formation of deoxyribose from ribose is what type of reaction (oxidation or reduction)
Reduction
-Gained a hydrogen
RIG
Rate limiting enzyme of purine breakdown
Xanthine oxidase
DNA replication occurs during the ___ phase of the cell cycle
S phase
DNA replication occurs in the _____ of the cell
nucleus
