Metabolic Pathoways; Bioenergetics Flashcards
Isocitrate Dehydrogenase
-rate limiting enzyme of Krebs cycle
During Krebs Cycle _____
CHO
- CO2 produced
- H+ atoms are removed to go to the ETC
For each Krebs cycle _____
CHO
- 3H+ picked up by 3 NAD+ (9 ATP)
- 1 H+ picked up by FAD+ (2 ATP)
- 1 direct ATP
Cytochromes
CHO
Iron-protein carries in ETC that pass along H+
Krebs cycle directly forms
CHO
1 ATP per cycle
In krebs cycle, H+ atoms are _____
CHO
-picked up by NAD+ & FAD+
Phosphofructokinase
-rate limiting enzyme in anaerobic glycolysis
Cytochrome Oxidase
-rate limiting enzyme of ETC
Cytochrome Oxidase Inhibited by:
increased levels of ATP
Types of chemical reactions
- endergonic: needs energy to react
- exogonic: reaction releases energy
Large incr/decr in temperature=_____
enzymes
decr enzyme activity
Electron Transport Chain
CHO
- oxidative phosphorylation or respiratory chain
- H+ picked up by NAD+ and FAD+ are passed along by series of cytrochromes
H+ eventually _____
CHO
accepted by oxygen to make H2O
Krebs cycle
carbs
- in mitochondria
- part of aerobic glycolysis
For each NADH _____
CHO
- 3 ATP formed (theory)
- 2.5 ATP (actual)
Total # ATP from Krebs Cycle
CHO
- 12 ATP
- 1 directly, 11 via ETC
Maximal capacity for aerobic glycolysis____
CHO
- is great
- Long duration ex’s
1 mole glucose–>36 ATP (theoretical), 30 ATP (real)
1 mole glycogen–>37 ATP (theoretical), 31 ATP (real)
For each FADH_____
CHO
- 2 ATP formed (theory)
- 1.5 ATP (actual)
Triglyceride + 3 H2O==>_______
==>glycerol + 3 fatty acid chains
Fats go through ______ before entering Krebs cycle
beta oxidation
During beta oxidation ____ ATP formed per _____
- 5 ATP
- 2 carbon segment
Bioenergetics
- process that converts fats, proteins & carbs into forms the body can use
- involves chemical reactions that are regulated by enzymes
Enzyme
- proteins that regulate the rate at which reaction takes place
- affected by temp and pH
Small incr in temperature=____
increased enzyme activity
3 Energy Sources
- carbohydrates
- fats
- proteins
What form of CHO is used to make ATP?
glucose
1 gram of CHO=
4 kcal of energy
Enzymes & pH
- enzymes have own optimal pH range
- outside range=decr activity
Carbohydrates
- carbon, oxygen & hydrogen
- rapid source of fuel
-1 gram CHO=4 kcal of energy
CHO
carbohydrates
Amount ATP produced from Protein:
-depends on amino acids and where it enters the process
Proteins provide ATP for:
- long term ex’s
- malnutrition
Proteins require that ____ be removed from the _____
- nitrogen
- amino acid
Quick bursts of activity
- <5 seconds
- ATP-PC system
5-45 seconds of activity
anaerobic glycolysis
What form of fats is used to make ATP
- glycerol
- free fatty acid chain
form of proteins used to make ATP?
amino acids
1 gram of fat=
9 kcal of energy
Fats
- carbon, hydrogen & oxygen
- energy for prolonged ex’s
1 gram proteins=
4 kcal of energy
ATP
mechanical energy the body utilizes comes from the break down of ATP
ATP Made via Aerobic Glycolysis
Cardiac Muscle
Glucose: 38 theory, 32 reality
Glycogen: 39 theory, 33 Reality
ATP Made via Aerobic Glycolysis
Skeletal Muscle
Glucose: 36 theory, 30 reality
Glycogen: 37 theory, 31 reality
Energy is released when ATP _____
- joins H2O in the presence of ATPase
- to break down into ADP + Pi
3 ATP-Making Systems
- phosphagen system
- anaerobic glycolysis
- aerobic glycolysis
Proteins
- carbon, H+, O2, Nitrogen, Sulfer, phospherous, Iron
- energy source in malnutrition & prolonged exercise
Phosphagen System
- (ATP-PC System)
- Anaerobic
- Immeidate
ATP + H2O _______
ADP + Pi + ENERGY
via ATPase
How much ATP stored in Mm Cell?
- very little
- only enough to perform max ex’s for several seconds
Anaerobic glycolysis
- (lactic acid system)
- use chemicals from food break down
- anaerobic
- intermediate
Aerobic glycolysis
(Oxygen System)
- Use chemicals fro food break down
- aerobic
- slow
Isocitrate dehydrogenase inhibited by:
- increased ATP
- Increased NADH
Cytochrome oxidase activated by:
incr levels ADP & Pi
Beta Oxidation
- process where free fatty acids are broken into 2-carbon chains
- use 1 ATP to activate fat to go through beta oxidation
Fuel utilization at rest
-liver glycogen/blood glucose & fats are primary methods of ATP production
2 Steps of Phosphagen System
- PC broken down by creatine kinase & releases energy
- energy used to combine ADP & Pi to make ATP
Phosphagen system is fast because it’s a ___-step process & _______
- 2 step
- creatine already present in body
creatine kinase is a ___ limiting enxyme for ___
- rate
- ATP-PC System (phosphagen)
PC
- phosphocreatine
- high energy phosphate used on phosphogen system to make ATP
Creatine kinase inhibited by_____
incr levels ATP in sarcoplasm
CP
creatine phosphate
Creatine kinase activated by_____
incr levels ADP in sarcoplasm
Break down of CHO in GI system=
- glucose
- fructose
- galactose
(all changed to glucose in liver)
Glucose is broken down into _____
- 2 molecules pyruvic acid
- which provides energy to add a Pi to ADP
2 Phosphagen System Steps
- PC Pi + C + Energy
2. Energy + ADP + Pi ATP
Maximal power of phosphagen is _____ because _____
- great
- provides energy fast for short quick bursts of activity
Anaerobic Glycolysis is a ____-step process
10 steps
in cytoplasm
Phosphagen system yields _____ ATP
- 1 ATP per PC
- very fast
Anaerobic glycolysis involves the break down of ____
- CHO
- can only use CHO
ATP Made per molecule of Fat=
3[17(#carbon segments-1)+12-1]
Anaerobic glycolysis yields ____ ATP
-1 glucose molecule nets 2 ATP and grosses 4 ATP
Glucose can travel in ___ or ____
- travel in blood
- be stored in muscle cell or liver
Glycogen
-storage form of glucose
during ex’s ATP production______
decr
as glucose passes from blood through the cell wall it’s
phosphorylated (Pi added)
Once in the cell, glucose is broken down to form ____ & the break down _____
- lactic acid
- releases energy to form ATP
During anaerobic glycolysis 2 ____ are formed and picked up by ____
- H+
- NAD (taken to ETC in mitochondria)
Anaerobic metabolism occurs in_____
cytoplasm
during anaerobic glycolysis, if ATP not needed now_____
the energy is stored as glycogen for later
ETC
- electron transport chain
- in mitochondria
Once glycogen is in the muscle cell_____
it can’t leave to help other cells make ATP
maximal power of anaerobic glycolysis is ____
- intermediate
- provide ATP for moderate activity
(1.6 mole ATP/min)
Aerobic glycolysis
- requires O2
- uses CHO, proteins & fats as fuel
Deamination
-process where nitrogen is removed from amino acids in liver
some proteins converted to ____, _____ & _____
- pyruvate
- acetyl Co A
- Kreb’s cycle
Example of Amino Acids used
- leucine
- isoleucine
- valine
- glutamine
- aspartate
Lactate Threshold
anaerobic threshold
point where aerobic metabolism can’t supply enough ATP and must use anaerobic metabolism
Fuel source for anaerobic ex’s
-stored ATP-PC & muscle glycogen are main sources of ATP
Increased need for ATP during ex’s comes from ____ then ____
- incr aerobic metabolism to a point
- at 50-60% max VO2 need can’t be met by aerobic metabolism and aerobic is needed
In presence of O2 pyruvic acid_____
-doesn’t form lactic acid but is metabolized and enters krebs cycle
Transamination
-process where nitrogen is removed from amino acides in muscle
phosphorylase
converts glycogen to gluose
1-2 min of activity
ATP-PC system, anaerobic glycolysis and aerobic metabolism
Full use during ex’s
- gradual shift from CHO to fats after 1/2 hour ex’s
- after 1 hour=small amount of protein
Isocitrate dehydrogenase activated by:
-incr ADP, NAD and mitochondrial Ca++
PFK activated by:
(phosphofructokinase)
-incr levels of AMP, ADP and pH
PFK inhibited by_____
- incr levels of ATP, CP, citrate
- decr levels pH
Before fat can be metabolized to produce ATP _____
it must be broken down by the enzyme lipase into glycerol & 3 fatty acids
Fuel source during aerobic ex’s
- decr intensity=incr fat use
- incr intensity=incr CHO use
in order for glucose to get into muscle cell:
- insulin needed
- 1 ATP used
- hexokinase needed
- magnesium needed
