Exam 3 Review Flashcards
Lipid categories?
- fatty acids
- triacylglycerides
- bilayer-forming
- Steroids
Fatty acids and TAGs?
FA: signaling; linked to backbones
TAGs: energy storage
Fatty Acids?
Can be:
Saturated- no double bonds
Monounsaturated- one double bond
Polyunsaturated- 2+ double bonds
Double bonds are cis 99% of the time.
-cis makes kinks, lowers M.P.
Membrane fatty acids have 16-20 carbons
Bilayer forming lipids?
Glycerophospholipids:
-have glycerol backbone, 2 acyls
Sphingolipids:
-have saturated FA tails, make membranes stiff
Steroids?
- Have flat planes
- 4 fused rings
- amphipathic/mostly hydrophobic
- interacts with nonpolar chains to make bilayer more rigid
Types of membrane proteins?
Peripheral membrane protein:
-interacts with membrane surface
Integral membrane protein:
-inserts partly in membrane
Transmembrane protein:
-spans entire membrane
3 lipids membranes will contain?
- Sphingolipids
- Glycerolipids
- Glycolipids
Fatty acid numbering conventions?
- m:n where m is the number of carbons and n is the number of double bonds
- Delta:n where n is dbl bond counting from ester
- w:n where n is the first dbl bond counting from the methyl end
Why are micelles formed?
Van der Waals forces cause micelles to form in fatty acids.
- hydrophobic effect drives nonpolar tails to minimize contact with water
- formed because amphipathic conical
Why do bilayers form?
Glycerolhospholipids and sphingolipids
Stable for amphipathic cylindrical.
Hydrophobic tails away from water
Hydrophilic heads contacting water
Role of lipids in membranes?
- Determine membrane properties
- control entry and exit of other molecules and ions
Reducing sugar?
Linear aldose’s are reducing sugars
- OH on anomeric Carbon
Cellulose?
Fibrous, insoluble structure. Plant cell walls, cotton, wood, paper
- D-glucose monosaccharide
- B 1-4 linked chains
Glycogen?
Storage in animals
-D-glucose monomer alpha1-4 links
- branches at alpha1-6
- every 8-12 residues
Starch?
Storage in plants
Mix of two D-glucose monomers
- Amylose:
- unbranched with alpha1-4 links - Amylopectin:
- branched with alpha1-6 links
- every 24-30 residues
Chitin?
- N-acetylglucosamine monomers
- B1-4 links
- forms tough, flexible, water insoluble material
Irreversible steps in glycolysis?
Step1: glucose->G6P
- hexokinase enzyme
- regulated
Step3: F6P->FBP
- PFK enzyme
- regulated
Step10:PEP->Pyruvate
- PK enzyme
- regulated
Step 1 glycolysis?
Glucose->Glucose 6 Phosphate
- Enzyme: hexokinase
- regulated, irreversible
- minus 1 ATP
Step 3 glycolysis?
Fructose 6 phosphate (F6P)
–>
Fructose 1,6 bisphosphate
(FBP)
- Enzyme: Phosphofructokinase (PFK)
- most regulated step, irreversible
- minus 1 ATP
Step 10 glycolysis?
Phosphoenolpyruvate
(PEP)
–>
Pyruvate
- Enzyme: Pyruvate Kinase (PK)
- regulated, irreversible
- plus 1 ATP
ATP investment steps glycolysis?
Step1: Glucose->G6P
- hexokinase
- minus 1 ATP
- irreversible and regulated
Step3:F6B->FBP
- PFK
- minus 1 ATP
- irreversible and regulated
NAD+ investment steps glycolysis?
Step 6: GAP->1,3 BPG
- GAPDH
- 2 NAD+ get reduced to NADH
- endergonic but coupled with step 7 to make neutral
ATP production steps glycolysis?
Step7: 1,3 BPG->3PG
-PGK
- 1 ATP produced per molecule (2 total for every 1 glucose)
- exergonic, coupled with step 6
Step10: PEP->Pyruvate
-PK
- 1 ATP produced per molecule (2 total for every glucose)
- irreversible and regulated
Glycolysis equation?
1 glucose, 2ATP, 2NAD+
–>
2 Pyruvate,4 ATP, 2 NADH
Fates of Pyruvate under normal conditions?
2 Pyruvate enter the TCA cycle under normal (aerobic) conditions
Fates of Pyruvate under hypoxic conditions in mammals?
2 Pyruvate-> 2 lactate
-LDH enzyme
-2NADH oxidized to
2NAD+
Fates of Pyruvate under hypoxic conditions in yeast?
Fermentation*
Oxidation rules
Carbon bonded to:
Oxygen= +1
Carbon= 0
Hydrogen= -1
Oxidation rules
Carbon bonded to:
Oxygen= +1
Carbon= 0
Hydrogen= -1
