Cellular Respiration Flashcards
Define metabolism.
The chemical processes that occur in cells that keep the organism alive.
What are the types of metabolism?
- Catabolic
- Anabolic
Define catabolic metabolism.
Reactions that release energy by breaking down complex molecules into simpler compounds.
(Catabolism)
(Catabolism is passive, meaning it doesn’t use energy.)
Define anabolic metabolism.
Reactions that consume energy to build larger, complicated molecules from simpler ones.
(Anabolism)
(Anabolism is active, meaning it uses energy.)
Define catabolic pathways.
Pathways that release energy by breaking down complex molecules into simpler compounds.
(Catabolism is passive, meaning it doesn’t use energy.)
Define anabolic pathways.
Pathways that consume energy to build larger, complicated molecules from simpler ones:
(Anabolism is active, meaning it uses energy.)
Give an example of a catabolic pathway.
Cellular Respiration.
Give an example of an anabolic pathway.
Photosynthesis.
How much energy from cellular respiration is turned into heat?
~60%
Why is the energy from cellular respiration turned into heat?
To maintain homeostasis.
What is the formula for cellular respiration?
C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + 38ATP
List 3 molucules that cellular respiration can release energy from.
- Glucose (mainly)
- Amino Acids
- Glycerol
Define phosphorylation.
When ATP gives a phosphate group to another molecule.
How is ATP formed?
ATP is formed when an inorganic phosphate group is joined to a molecule of ADP.
Which phosphate group in ATP’s bond can easily be broken, and what does it do if broken?
The third, and it releases energy.
What does ATP stand for?
Adenosine triphosphate.
What does NADH do in cellular respiration?
It’s used to carry electrons generated in Glycolysis and Kreb’s Cycle to the Electron Transport Chain.
Define Aerobic.
‘With oxygen’.
Define Anaerobic.
‘Without oxygen’.
What is the major energy currency in the cell?
ATP
(Adenosine Triphosphate)
In order:
What are the three stages of cellular respiration?
- Glycolysis
- Kreb’s Cycle
- Electron Transport Chain (ETC)
What is the meaning of glycolysis?
Glucose splitting.
Where does glycolysis take place?
The cytosol.
(or cytoplasm, more broadly.)
Is glycolysis catabolic or anabolic? Why?
Catabolic.
It uses energy to break down glucose into pyruvates.
What happens in glycolysis?
Each glucose molecule is converted into two pyruvates.
What is a pyruvate?
Chemicals produced as a result of glycolysis.
How much energy does glycolysis require?
2ATP
How much energy does glycolysis produce?
4ATP (but 2 is used to start the process) + 2NADH
Is glycolysis anaerobic or aerobic?
Anaerobic.
What is aerobic respiration?
The complete breakdown of glucose to carbon dioxide and water – requiring oxygen
What is aerobic respiration?
TODO
Where does aerobic respiration occur?
The mitochondria.
(Kreb’s Cycle & ETC)
Where does anaerobic respiration occur?
The cytoplasm / cytosol.
(Glycolysis)
What’s another name for the Krebs cycle?
The citric acid cycle.
Where does Kreb’s cycle occur?
Within the mitochondrial matrix.
What does Kreb’s cycle do to pyruvates?
It oxidises them into carbon dioxide, forming ATP and NADH
In Kreb’s cycle, each pyruvate releases…
1ATP + 3NADH.
How much energy is released from Kreb’s cycle in total?
2ATP + 6NADH
(1ATP + 3NADH per pyruvate)
Is Kreb’s cycle anaerobic or aerobic?
Aerobic.
What happens in the Electron Transport Chain?
(aka ETC)
Electrons are passed between molecules, resulting in oxygen molecules forming water.
What does the Electron Transport Chain require?
8NADH.
(Formed by Glycolysis and Kreb’s cycle.)
How much energy is output by the electron transport chain?
34ATP.
(No NADH, it’s only used for respiration to continue.)
Where does the electron transport chain occur?
The inner mitochondrial membrane.
If there’s no oxygen present for respiration, what happens?
Anaerobic respiration occurs.
What happens in anaerobic respiration?
The pyruvate produced in glycolysis is converted to lactic acid by fermentation.
How much ATP is produced in anaerobic respiration?
2ATP
(per glucose)
How much ATP is produced in aerobic respiration?
38ATP.
(per glucose)
When is anaerobic respiration important?
During vigorous physical activity, when the body cannot supply enough oxygen to meet demands.
What happens to lactic acid after it’s fermented?
- It makes its way to the liver
- Oxygen is added when it gets there
- It turns back into pyruvic acid and then back into glucose
(This process is active.)
