Download Learning Objectives

Learning Objectives - Exam 3
Carbohydrates:
Know the basic formula
Know the difference between Mono- vs. Oligo- vs. Polysaccharides
Understand that there are aldehydes and ketones
Be able to recognize the well known sugars (aldoses = ribose, glucose, mannose, galactose and ketoses
= fructose)
Recognize epimers
Realize that there are  and  anomers at carbon1
Be able to identify and define the anomeric carbon
Understand how a glycosidic bond forms
Be able to identify the reducing vs. nonreducing end of oligo- and polysaccharides
Know the components of well-known disaccharides (lactose, sucrose)
Know the basics of the well-known polysaccharides
Storage = starch, glycogen
Starch/glycogen made of amylose (14) and amylopectin (14 and 16)
Structure = cellulose, chitin
14 linkages
Why structural so rigid and storage are not? Related to 14 links vs. 14 links
Why can’t humans live on grass (cellulose)?
Metabolism:
Six principles – name them and describe something about them (an example, etc.)
Glycolysis - know ALL the details for the QUIZ, including net reaction, ATP/NAD used and made
Know importance of phosphorylated intermediates
What are the three nonequilibrium steps? How are each regulated?
Hexokinase
Phosphofructokinase-1
Pyruvate kinase
Understand enzyme mechanisms
Aldolase
Glyceraldehyde 3-phosphate dehydrogenase
Regulation of glycolysis
What is flux? What limits it?
What is homeostasis? What maintains homeostasis?
By cellular energy charge
By hormones
By coordination with other pathways
Citric acid cycle
What is it? What does it do? Where does it occur?
Know how pyruvate dehydrogenase complex works (cofactors involved, mechanism, regulation)
Know net reaction
Know where ATP, CO2, FADH2 and NADH are made
Know ultimate # ATP formed
Stereospecificity of aconitase, fumarase
Know how -ketoglutarate dehydrogenase complex works
What is only membrane-bound enzyme?
Regulation of citric acid cycle
Oxidative phosphorylation
What is it? Where does it occur?
Chemiosmotic hypothesis – what is it? experimental support for it
What are electron carriers? What proteins are they associated with?
Inhibitors of oxidative phosphorylation
Movement of electrons in Complexes I, II, III, IV
ATP synthase
Control & regulation
Gluconeogenesis
What three steps are different between glycolysis and gluconeogenesis?
Understand mechanisms of important enzymes:
Pyruvate carboxylase
Phosphoenolpyruvate carboxykinase
Fructose 1,6-bisphosphatase
Glucose 6-phosphatase (only in liver and kidney cells)
Futile cycles
Reciprocal regulation of glycolysis and gluconeogenesis (F26BP, AMP, citrate, glucagon, insulin)
Glycogen metabolism
Breakdown
Breakdown glycogen to produce glc because mobilized fast
Understand mechanism and control of Glycogen phosphorylase (muscle vs. liver)
Debranching enzyme
Glucose 1-phosphate
Synthesis
Synthesize glycogen mostly in muscle and liver
UDP-glucose pyrophosphorylase (used to make activated form of glc - UDP-glucose)
Glycogen synthase
Glycogenin
Branching enzyme
Understand Reciprocal control of breakdown & synthesis
(glucagon, epinephrine, insulin)
Know the Phosphorylation/dephosphorylation of key enzymes
Lipid metabolism
Breakdown
Know how fats metabolized by lipases (regulated step)
Understand that hormones trigger mobilization of stored triacylglycerols
Understand importance of "priming" fatty acid with CoA to make fatty acyl-CoA
Transport fatty acid into mitochondria using carnitine acyltransferase (regulated step)
-oxidation of fatty acids (breakdown)
even # carbons - get acetyl CoA and FADH2 and NADH
odd # carbons - get acetyl CoA and FADH2 and NADH + succinyl CoA
double bonds - extra enzyme step to isomerize double bond
Know how the process is regulated by:
Acyltransferase as rate-limiting step
Malonyl CoA (synthesis molecule)
NADH
Acetyl CoA
Ketone bodies
Why/when do these form?
Acetone, acetoacetate, -hydroxybutyrate
Lipid biosynthesis
Know the classes of lipoproteins and the lipids they carry
Know the committed step of synthesis - acetyl CoA carboxylase to make malonyl CoA
Fatty acid synthase
All enzyme activities on one enzyme
Addition of malonyl CoA each time
Uses NADPH
Understand regulation of lipid metabolism by
Committed steps
Hormones
Cholesterol synthesis
Important enzyme = HMG CoA reductase (how regulated?)
High cholesterol and heart disease
Use of lovastatin
Other metabolic pathways
Pentose phosphate pathway
Produces NADPH and ribose 5-phosphate - what are these used for?
Amino acid metabolism
Breakdown to get amino groups (nitrogen)
Breakdown with HCl and proteases in stomach and intestines
Urea cycle - way to excrete NH4 out of body
Understand how the urea cycle is regulated
Know what it means to be an essential vs. nonessential amino acids
Know the enzyme cofactors used in AA metabolism
tetrahydrofolate, S-Adenosylmethionine
Know what it means to be a glucogenic vs. a ketogenic AA
Genetic defects affecting AA metabolism- phenylketonuria
Other roles of AAs
Integration & Hormone regulation
Use this note packet as a study/review tool
Understand the organ specialization during metabolism
Know the branchpoints in metabolism
Understand all the ways that hormone control affects metabolism