U2 Respiration Flashcards
What is ATP? +uses
A high-energy compound capable of releasing energy for:
-muscle contraction
-synthesis reactions
-active transport
-etc.
What is ATP made up of? and what is it broken down into?
One adenosine
3 inorganic phosphate groups
Broken down into ADP + Pi (energy released)
What is phosphorylation?
the addition of a phosphate group
What does ATP act as a link between?
energy-releasing reactions and energy consuming reactions
Glucolysis-4 facts
It is the first stage of aerobic respiration
It occurs in the cytoplasm
Does not require oxygen
Glucose (6 carbon sugar) is broken down into two molecules of pyruvate (3 carbon molecule) in a series of enzyme controlled reactions
What is ATP required for in glycolysis?
Describe the energy investment phase and the energy pay-off phase.
The phosphorylation of glucose and intermediates during the series of reactions
This requires an investment of 2 ATP molecules in the ENERGY INVESTMENT PHASE
but results in the generation of 4 ATP molecules in the ENRRGY PAY-OFF PHASE
NET GAIN of 2 ATP molecules
What holds the carbons in a 6 carbon glucose molecule together?
hydrogen bonds
glycolysis-What happens when the 6C glucose molecule is split?
hydrogen ions and electrons are released and must bind to a carrier
The carrier in glycolysis is NAD which becomes NADH when carrying hydrogen molecules
1-the enzyme dehydrogenase removes the hydrogen ions and electrons from the glucose
2-they are temporarily bound to a coenzyme (NAD) which acts as a hydrogen acceptor and carrier
3-NAD carries the hydrogen ions and electrons to the Electron Transport Chain to be used later
Where is the Electron transport chain?
Inner membrane of the mitochondria
Where does the citric acid cycle take place?
matrix of the mitochondria
What happens after glycolysis?
If oxygen is present pyruvate diffuses into the matrix
where it loses a carbon atom to become acetyl
The carbon is released as CO2 and is released from the cell
What does the acetyl group join with?
a molecule called co-enzyme A forming acetyl co-enzyme A. The co-enzyme transports the acetyl group to the citric acid cycle
After acetyl has been transported to the citric acid cycle, what does it combine with? +what is it followed by?
oxaloacetate to form citrate.
This is followed by several enzyme controlled steps.
This cycle will eventually lead to the regeneration of oxaloacetate.
How many ATP molecules are generated in the citric acid cycle
1 molecule per pyruvate
What is released throughout the citric acid cycle?
Carbon dioxide
What is the Electron Transport Train?
The final stage of the respiration pathway.
This is where most ATP is produced.
It is a collection of proteins on the inner membrane (crustal) of the mitochondria
A series of carrier proteins attached to the inner mitochondrial membrane.
What is the inner membrane (crustal) of the mitochondria made up of?
proteins and phospholipids like any membrane
Where are the electrons from in the electron transport chain?
The NADH from glycolysis and citric acid cycle release the electrons and pass them to the electron transport chain
Stages of the electron transport chain
1-Electrons are passed along the chain, releasing energy
2-This energy is used to pump H+ across the inner mitochondrial membrane, creating a higher concentration outside of the matrix
3-H+ then flows back in across the membrane via molecules of ATP synthase. This enzyme converts ADP+Pi into ATP
How is the majority of the ATP produced during cellular respiration generated?
Electron Transport Chain
ETC-What is the final electron acceptor?
Oxygen is the final electron acceptor and combines with the electrons and hydrogen ions that reach the end of the chain to make water.
3 features of fermentation
occurs when oxygen is absent
only glycolysis can occur
the process of fermentation is different in plants and animals
Fermentation in plants and yeast
glucose->2pyruvate->ethanol + CO2
first stage=net gain of 2ATP
Irreversible
Fermentation in animals
glucose->2pyruvate->lactation
first stage=net gain of 2ATP
oxygen debt build up converts pyruvate into lactate.
When oxygen debt is repaid, lactate is converted back into pyruvate (reversible)
How many ATP are produced per molecule of glucose during aerobic respiration?
38ATP
How many ATP are produced from 1 molecule of glucose during fermentation?
2ATP
(only produced during glycolysis->netbgain)
What is metabolic rate?
The quantity of energy consumed per unit of time
How can metabolic rate be measured?
energy production (heat) per unit of time
oxygen consumption per unit of time
CO2 production per unit of time
What is a calorimeter used for?
To measure metabolic rate. Energy production (heat) per unit of time is recorded
What is a respirometer used for?
To measure metabolic rate.
Probes can be used to detect changes in CO2 and O2 concentration
