BICH 411 Exam 1
What are the 4 functions of metabolism? - ANS-1. Obtain free energy for the cell
2. Degrade macromolecules as required for biological function
3. convert nutrients into macromolecules
4. Assemble macromolecules into cellular structures
What is catabolism? function? oxidative or reductive? - ANS-degradative pathways
produce free energy
oxidative
What is anabolism? function? oxidative or reductive? - ANS-biosynthetic pathways
consuming free energy
reductive
ATP is formed via ________ in phototrophic cells or __________ in heterotrophic cells -
ANS-photosynthesis
catabolism
Draw the structure of ATP, ADP and AMP - ANS-
Why is ATP a "high energy" compound? - ANS-hydrolysis --> increased resonance
stabilization, decreased electrostatic interaction, increased energy of solvation
Draw the structure of NADH and NADPH - ANS-
What is the function of NAD+? NADH? - ANS-collects electrons released in catabolism
NADH is the most common e- carrier, always transfers two e- at a time
Draw the structure of oxidized and reduced NADH - ANS-
LEO the lion says GER - ANS-Loss of electrons is oxidation, gain of electrons is
reduction.
,What is the function of NADPH? - ANS-provides the reducing power for anabolic
processes
oxidative precursor - reductive biosynthetic reactions - reduced biosynthetic product
NADPH --> NADP+
NADPH can be viewed as the carrier of electrons from catabolic reactions to anabolic
reaction
How do the pathways of catabolism converge to a few end products? - ANS-catabolism
converges to three principal end products: water, carbon dioxide and ammonia
What are the three stages of catabolism? - ANS-1. proteins, polysacch and lipids
broken into building blocks
2. building blocks are degraded into common products: acetyl groups of acetyl-CoA
3. catabolism converges to three principal end products: water, carbon dioxide and
ammonia
What are the two ways to manage catabolism and anabolism? - ANS-1. cells maintain
tight and separate regulation of catabolism and anabolism so metabolic needs can be
met
2. metabolic pathways are localized within different cellular compartments
(COMPARTAMENTALIZATION)
Describe bonds in an endothermic reaction? - ANS-head is absorbed
new bonds are less stable
Describe bonds in an exothermic reaction? - ANS-heat is evolved by the system
new bonds are more stable
What are the three thermodynamic equations? - ANS-1) ∆G = ∆H -T∆S
2) ∆G = ∆G°+ RT ln([P]/[R])
, 3.) ∆G° = -RT lnKeq
What are biosynthetic enzymes? - ANS-operate as part of anabolic pathways (reductive
biosynthesis)
What are degradative enzymes? - ANS-operate as part of catabolic pathways (oxidative
degradation)
What are vitamins? - ANS-organic molecules acquired through diet that assist metabolic
reactions
What are the water soluble vitamins? - ANS-almost always converted to coenzymes
What are fat soluble vitamins? - ANS-ADEK and are stored for longer periods of time
How are metabolic pathways controlled? (3) - ANS-thermodynamics,
compartamentalization, metabolic flux
What is metabolic flux? What are 4 types? - ANS-regulation of key enzymes
1. allosteric control
2. covalent modification
3. substrate cycles
4. genetic control
What are the 2 phases of glycolysis? - ANS-1. Energy investment phase (2 ATP)
2. Energy payback phase (4 ATP)
Why is PEP such a high energy intermediate? - ANS-enol phosphate
large -ΔG° ́, potent phosphorylating agent
1. Hydrolysis of a phosphate group (PEP--> pyruvate)
2. tautomerization (PEP enol --> keto)
What are three high energy intermediates? - ANS-PEP
1,3-BPG
PC
What are the 4 functions of metabolism? - ANS-1. Obtain free energy for the cell
2. Degrade macromolecules as required for biological function
3. convert nutrients into macromolecules
4. Assemble macromolecules into cellular structures
What is catabolism? function? oxidative or reductive? - ANS-degradative pathways
produce free energy
oxidative
What is anabolism? function? oxidative or reductive? - ANS-biosynthetic pathways
consuming free energy
reductive
ATP is formed via ________ in phototrophic cells or __________ in heterotrophic cells -
ANS-photosynthesis
catabolism
Draw the structure of ATP, ADP and AMP - ANS-
Why is ATP a "high energy" compound? - ANS-hydrolysis --> increased resonance
stabilization, decreased electrostatic interaction, increased energy of solvation
Draw the structure of NADH and NADPH - ANS-
What is the function of NAD+? NADH? - ANS-collects electrons released in catabolism
NADH is the most common e- carrier, always transfers two e- at a time
Draw the structure of oxidized and reduced NADH - ANS-
LEO the lion says GER - ANS-Loss of electrons is oxidation, gain of electrons is
reduction.
,What is the function of NADPH? - ANS-provides the reducing power for anabolic
processes
oxidative precursor - reductive biosynthetic reactions - reduced biosynthetic product
NADPH --> NADP+
NADPH can be viewed as the carrier of electrons from catabolic reactions to anabolic
reaction
How do the pathways of catabolism converge to a few end products? - ANS-catabolism
converges to three principal end products: water, carbon dioxide and ammonia
What are the three stages of catabolism? - ANS-1. proteins, polysacch and lipids
broken into building blocks
2. building blocks are degraded into common products: acetyl groups of acetyl-CoA
3. catabolism converges to three principal end products: water, carbon dioxide and
ammonia
What are the two ways to manage catabolism and anabolism? - ANS-1. cells maintain
tight and separate regulation of catabolism and anabolism so metabolic needs can be
met
2. metabolic pathways are localized within different cellular compartments
(COMPARTAMENTALIZATION)
Describe bonds in an endothermic reaction? - ANS-head is absorbed
new bonds are less stable
Describe bonds in an exothermic reaction? - ANS-heat is evolved by the system
new bonds are more stable
What are the three thermodynamic equations? - ANS-1) ∆G = ∆H -T∆S
2) ∆G = ∆G°+ RT ln([P]/[R])
, 3.) ∆G° = -RT lnKeq
What are biosynthetic enzymes? - ANS-operate as part of anabolic pathways (reductive
biosynthesis)
What are degradative enzymes? - ANS-operate as part of catabolic pathways (oxidative
degradation)
What are vitamins? - ANS-organic molecules acquired through diet that assist metabolic
reactions
What are the water soluble vitamins? - ANS-almost always converted to coenzymes
What are fat soluble vitamins? - ANS-ADEK and are stored for longer periods of time
How are metabolic pathways controlled? (3) - ANS-thermodynamics,
compartamentalization, metabolic flux
What is metabolic flux? What are 4 types? - ANS-regulation of key enzymes
1. allosteric control
2. covalent modification
3. substrate cycles
4. genetic control
What are the 2 phases of glycolysis? - ANS-1. Energy investment phase (2 ATP)
2. Energy payback phase (4 ATP)
Why is PEP such a high energy intermediate? - ANS-enol phosphate
large -ΔG° ́, potent phosphorylating agent
1. Hydrolysis of a phosphate group (PEP--> pyruvate)
2. tautomerization (PEP enol --> keto)
What are three high energy intermediates? - ANS-PEP
1,3-BPG
PC
