What is galactosemia?
deficiency in transferase in the glucose utilization pathway
what is glucose stored as in animals?
glycogen
where is glycoen most found in?
liver and muscles
what is glucose stored as in plants?
amylose and amylopectin
which lipids can be used as fuel sources?
free fatty acids and triglycerols
free fatty acids
common source of fuel
triglycerides
storage form of fatty acids
phospholipids
membrane lipids
glycolipids
membrane lipids composed in part of carbohydrates
steroids
polycyclic hydrocarbons with a variety of functions
saturated fatty acids
no double bonds
how many carbons does fatty acids have?
16/18
a fatty acid with a short chain length and many double bonds will have a _____ melting point
lower
what type of fatty acid will be the most fluid?
one that has less carbons and is unsaturated
steps of lipid digestion
1) lipases convert trigylercols into 2 fatty acids and monoglycerol
2) carried to intestine for absorbtion
3) trigylerols are reformed and packaged in chylomicrons
fatty acid processing steps
1)degradation of TAGs release fatty acids ad glycerol into blood for transport (lipolysis)
2)activation of fatty acids and transport into mitochondria for oxidation (Beta oxidation)
3)degratadtation of FA to acetyl CoA to use in CAC
what is lactose composed of
glucose and galactose
what enzymes are used in the energy investment site of glycolosis?
phosphofructokinase and glyceraldehyde 3 phosphate
what enzymes are use din the energy harvesting step of glycolosis
phosphoglycerate kinase,
where does fructose enter in the liver
DHAP and GAP
where does glucose enter in adipose tissue
fructose 6 phosphate
kineticallly perfect enyzem of glycolosis
triose phosphate isomerase
rate determining enzyme of glycolosis
phosphofructokinase 1
glucose transport that is glucose dependant and is found in muscle and adipose tissue
GLUT4
glucose transporter that is glucose independant and found in liver and pancreatic cells and has high Km for glucose
GLUT2
which enzyme in glycolosis uses NAD+ as a stoichiometric enzyme?
glyceraldehyde 3 phosphate dehyndrogease
which enzyme of both glycolosysis and glucoseneogensis catalyzes reversible reaction of 2PG to PEP?
enolase
glucose to lactose fermentation produces how many net ATP?
2
how muchatp is produced in the complete oxidation of glucose?
30
which coenzyme is a activated carrier of acyl groups and acts as a swinging arm?
lipoamide
how are the alpha ketoglutarate complex of the CAC similar to the pyruvate dehydrogenase complex of glycolosis
both have 3 enzymes and 5 coenzymes
cori cycle
lactate is produced in muscles, used to produce glucose in the liver
what is the potent activator of the pyruvate dehydrogenase complex
ADP
what is the reducing agent of alchohol fermentation?
NADH
which enzyme is the physical link to the CAC?
succtinae dehydrogenase
which enzyme catalyzes sbstarte level phosphorylation in the CAC?
succinyl CoA synthase
which two CAC enzymes are inhibited by ATP and NADH
a-ketogluterate dehydrogenase and isocitrate dehydrogenase
which enzymes replenishes anabolic intermediates in the CAC?
pyruvate carboxylase
how much ATP does lactose oxidation generate?
60
which class of enzymes add water to a double bond?
lyases
what are the three main precursors that generate glucose in gluconeogenesisis?
amino acids, glycerol, and lactate
where does glucoseneogenesisi take place?
cytosol (G6P in ER lumen and pyruvate carboxylase in mitochondria
glucoagon sinaling cascades ____ phosphorfructokinas and activates ____
phophorylates, gluconeogenesis
what inhibits hexokinase in resting skelatal muscles?
G6P
what are the recipricolly regulate enzymes of glycolosis and gluconeogenesis?
pfk1 and f1,6bp
which key intermediate is shuttled in/out of the mitochondria by malate dehydrogenase?
oxoloacetate
what enzyme class are G6P and F1,6BP part of
transferases
which group of enzymes are activated in lipolysis?
homorone simulated lipases
What shuttle is utilized to transport activated fatty acids from the cytosol across the mitochondrial membranes?
carnitine shuttle
Fatty acid metabolism is controlled by the committed step of fatty acid synthesis, which is the formation of _______________, catalyzed by __________________.
malonyl CoA; acetyl CoA carboxylase
Which enzyme in fatty acid metabolism uses FAD+as a catalytic coenzyme?
acyl CoA dehydrogenase
In the electron transport chain, electrons from flavoproteins transfer their electrons to the small electron carrier embedded in the innermembrane called _________________
ubiquonol
Which electron transport complex is unable to generate sufficient free energy to power ATP synthesis?
succinate Q reductase
Because cytochrome C can carry _______ electron(s) at a time, ________ cytochrome C molecules are required to be oxidized by Complex IV to reduce one molecule of oxygen
1,4
What are the principle physiological electron donors for the mitochondrial electron transport pathway?
NADH and FDH2
what is the effect of etc inhibition on oxidative phosphorylation
disable ETC
The catalytic headpiece of the ATP synthase enzyme is primarily composed of which subunits?
a hexameric ?3?3 ring
he binding charge mechanism states that rotation of the ____ subunit of ATP synthase causes the _____ subunit to change from tight conformation where ATP is produced to open conformation where ATP is released
y, b
What is the relationship between number of c rings and amount ofprotons flowing through ATP synthase?
less c rings less protons
In mammals, __________ houses the main storage of triacylglycerols, while ___________ stores most of the glycogen
adipose tissue; muscle
low blood glucose levels _______ insulin
increase
What is the major fuel source for ATP production that is used in a long-distance runner?
muscle glycogen
Excess alcohol consumption leads to a buildup of which two key molecules?
acetyl CoA and NADH
During prolonged starvation, what are the major sources of metabolic fuel?
Ketone bodies and fats
A steep drop in blood glucose concentration occurs after consumption of high glycemic index foods because of a spike in
insulin
Thrifty genes are ________ during times of starvation and ________ when physical activity is low.
beneficial, detrimental
which three compunds have a hghr transfer potential than ATP?
phosphophenyl pyruvate, 1,3-biphosphoglycerate, ceatine phosphate
Coenzyme A is derived from this vitamin: ___________, and coenzyme A is an activated carrier for this functional group: ____________.
pantothenic acid, acyl groups
what value will favorable reactions have
-delta G
What reaction is catalyzed by aldolase?
reversible cleavage of Fructose-1,6-bisphosphate (F-1,6-BP)to DHAP and GAP
Which of the following compounds contains a "high-energy" bond and is used to produce ATP by substrate-level phosphorylation in glycolysis?
1,3-bisphosphoglycerate
In glycolysis, what is the function of glyceraldehyde 3-phosphate dehydrogenase?
oxidation of an aldehyde by NAD+and formation of acyl-phosphate
Glucose is converted to ______ in skeletal muscle under anaerobic conditions
lactate
An infantwho obtains nourishment from milk and who has galactosemia (i.e., has a deficiency in galactose-1-phosphate uridyltransferase) is unable to convert:
galactose-1-phosphate to glucose-1-phosphate
Which of the following is the primary mode of regulation for the pyruvate dehydrogenase complex?
inhibition by phosphorylation
Which of the following is an allosteric inhibitor of phosphofructokinase both in the muscle & in the liver?
ATP
Which of the following metabolic conversions is considered to be therate-determining step of glycolysis, and thus amajor control point of glycolysis?
fructose-6-phosphate �fructose-1,6-bisphosphate
The primary raw materials for gluconeogenesis are:
lactate , alanine, glycerol
he irreversible glycolytic step catalyzed by pyruvate kinase is bypassed in gluconeogenesis by the action of these two enzymes:
pyruvate carboxylase& phosphoenolpyruvate carboxykinase
Insulin stimulates a signaling cascade that leads to the _______________ of the bifunctional protein phosphofructokinase 2/ fructose bisphosphatase 2, which results in the activation of ______________
dephosphorylation, glycolosis
n order for a fatty acyl-CoA to be moved into the mitochondria for beta-oxidation, it must be
cartinine
what class of enzymes break double bonds?
lyases
What is the committed step in fatty acid synthesis?
Synthesis of malonyl CoA by acetyl CoA carboxylase
Which of the following is considered a product of the citric acid cycle?
carbon dioxiide
Which citric acid cycle is also a key intermediate in gluconeogenesis?
oxoloactetate
Which of the following enzymes are thekey regulatory sitesin the citric acid cycle?
a-ketoglutatrate and icrate dehydrogenase