Chem: Carbs Flashcards
__ kcal/g
4 “fuel factor”
glycogen is storage form of??
carbs incytosol
Ketone?
multiple hydroxy groups
energy storage ?
coenzymes, RNA, DNA
Levoratory configuration of asymmetric carbon farthest from keto group
OH on the left
Levo=Left
Dextrorotatory configuration of asymmetric carbon farthest from keto group
OH on the Right
Dextro=Right
simple carb??
sugars with 1 or 2 single sugars
complex carb??
many sugar units
sorbitol is??
sugar alcohol from glu & converted into fru
found: berries, cherries, plums, pears
used: to make sweeteners- excess can cause diarrhea
polysaccharides??
complex CHO’s made of many single sugar units
oxidation means?
increasing positive charge or loss of negative charges
reduction means??
additionof hydrogen
gain of electrons
OIL RIG
oxidized is lost
reduced is gain
prebiotic in vivo=
fructans
10 grams = how many kcal?
40kcal
what hormones raise blood glucose?
glucagon EPI glucocorticoids thyroxine GH
catabolic pathways?
glycolysis
pyruvate oxidation
citric acid cycle
oxidative phosphorylation
catabolic pathways depend on?
conc. of ATP, ADP, & AMP
- if ATP is high, then the pathways are low\
- if ATP is low then the pathways are activated
CHO bonds are__?
glycosidic alpha-digestible beta-indigestible straight chain-1-4 branched chain 1-6
monosaccharides ex:
glucose; 6 carbons; Aldose; dextrose, corn syrup
Fructose; 6 carbons; Ketose; fruits, honey
Ribose; 5 carbons; Aldose; nucleic acids
Sorbitol; fruits, honey
Mannitol; pineapples, olives, sweet potatoes
Disaccharides & oligosaccharide ex:
Maltose; alpha1-4; glu + glu
lactose; beta1-4; glu + gal
sucrose; a-b 1-2; glu + fru
trehalose; alpha 1-6; isomaltose; mushrooms, yeast
polysaccharides ex:
cellulose; b1-4; fiber
amylose (linear); a1-4; plant starch
amylopectin; a1-4>a1-6; plant starch; branch every 24-30 glu
glycogen; a1-4>a1-6; animal strach; branch every 8-12 glu
non-cellulose polysaccharides
abosrb water, swell, slow emptying of food mass
bind bile acids to chol.
sources: hemicelluose, pectins, gums, mucilages, algal (seaweed)
ligin?
only non-carb type of dietary fiber (from woody part of plant)
carbs are digested in?
mouth-ptyalin starch>dextrins>maltose
none in stomach
SI breaks down carbs using enzymes: sucrase, lactase, maltase etc.
most abundant GAG?
chondroitin
Glut 2=
liver, kidney, beta cells
transports are coupled with sodium
Glut 4=
adipose, skeletal, cardiac
sensitive to insulin
Glut 5=
fru absorption; brushborder
prtoeoglycan=
protein core, repeating disaccharide
SGLT 1=
SGLT 2=
glu & gal absorption in intestines
kidneys
carboxylation=
carboxyl group is added
carboxylase catlyzes the addition
kinase is?
enzyme that transfers a phosphate group
isomerase does?
changes the configuration but not the composition of a compound
mutase does?
moves one group to another part in the same chemical compound
transferase does?
catalyzes the transfer of a functional from one molecule to another
ligase?
catalyzes the joining of two molecules
VMAX refers to?
the maximum velocity of a reaction
Kmax ?
substrate conc required to reach 1/2 of the Vmax
competitive inhibition is?
inhibitor binds to the same active site as a normal enzyme w/o undergoing a reaction.
reversible. Vmax will not change
non-competitive inhibition?
inhibitor always bind to a site other than the enzymes active site. is irreversible.
reduces Vmax
allosteric regulation?
enzymes activity is regulated by binding an effector molecule at the enzymes allosteric site
allosteric activators?
effectors that enhance the proteins activity
allosteric inhibitors?
decrease protein activity
catabolism results in?
heat generation
ATP synthesis
it is a degradative process that breaks down large molecules into smaller units, releasing useful energy
Anabolism is?
biosynthetic process that constructs large molecules from smaller units- requires energy
peptide bond is?
covalent bond
carboxyl reacts to amino group of another molecule
releases a water molecule (dehydration or condensation reaction)
ester bond is the chemical covalent bond between ?
glycerol and FA
phosphodiester is?
chemical bond bwn two nucleotides
FA oxidation, TCA cycle, oxidative phosphorylation occur in?
mitchondria
glycolysis, FA synthesis, HMP shunt & protein synthesis occur in?
cytoplasm
heme synthesis, urea & gluconeogensis occur in?
both mitochondria & cytoplasm
rate limiting step of: glycolysis
PFK** Most important**
rate limiting step of: gluconeogenesis`
fru 1,6 bisphospahtase
rate limiting step of: TCA cycle (krebs)
isocitrate dehydrogenase
rate limiting step of: glycogen synthesis
glycogen synthase
rate limiting step of: glycogenolysis
glycogen phosphorylase
rate limiting step of: HMP shunt
G6PD
rate limiting step of: urea cycle
carbamoyl phosphate synthetase
rate limiting step of: FA synthesis
acetyl co-a carboxylase
rate limiting step of: FA oxidation
carnitine acyltransferase
rate limiting step of: chol. synthesis
HMG co-A reductase
GLUT 1=
RBC, brain, placenta, testis
GLUT 3=
neurons
4 possible fates of pyruvate
ocidation
reduction
carboxylation
transamination
Krebs cycle has 8 steps:
Citrate Isocitrate Ketoglutarate Succinyl Co-A Succinate Fumarate Malate Oxaloacetate "Can I keep Selling Sex For Money Officer?"
Glycolysis has 10 steps:
2 phases
prep phase: 1. GLU>G6P 2. G6P>F6P 3. F6P>F1,6BP 4. F1,6BP>G3P & (DHAP) 5. DHAP>G3P Pay off Phase: 6. G3P> 1,3BP 7. 1,3BP> 3 phosphoglycerate 8. 3pg>2pg 9. 2pg> phosphoenolpyruvate 10. phosphoenolpyruvate>pyruvate
Gluconeogensis is?
glycolysis in reverse
Pathway Produces Fresh Glucose
what is produced in Krebs?
2 ATP
2 NADH+H= 6ATP
2Pyruvate to acetyl co-a= 6ATP
Acetyl co-a to Oxaloacetate= 24ATP
total: 38 ATP
purpose of pentose phopshate pathway (HMP shunt)
fatty acid synthesis
detoxification
protection from free radicals
