Lecture 11- Fermentation and Photosynthesis Flashcards
What are the two main feedback inhibition processes in cellular respiration?
- Phosphofructokinase is inhibited by ATP and stimulated by ADP. This is non-competitive inhibition.
- Pyruvate dehydrogenase (when pyruvate is changed into Acetyl to enter the mitochondria) is inhibited by ATP and NADH and stimulated by NAD+ and ADP.
How is pyruvate dehydrogenase also inhibited by NADH?
There is a limited supply of NAD+ in the cell. If all NAD+ are converted into NADH, pyruvate dehydrogenase can no longer occur.
What is anaerobic respiration?
When the electrons carried by high energy electron carriers are deposited on compounds other than oxygen. H2O is usually not a byproduct. This is used to make energy and to regenerate NAD+ in low O2.
What is fermentation?
When oxygen is scarce, the body will go through glycolysis, but instead of carrying out the krebs cycle, it will instead use the pyruvates to turn NADH to NAD+, leaving lactate. This process does not use O2.
What is ethanol fermentation?
When instead of lactate, the end product of fermentation is ethanol. Organisms such as yeast and bacteria do this to recycle their NAD+ anaerobically.
What is the equation for photosynthesis?
6 CO2 + 6 H2O –> C6H12O6 + 6 O2
Where does photosynthesis occur?
In the leaves of plants, more specifically in the chloroplasts of the cells.
What are the three series of reaction in photosynthesis?
- Capturing energy from sunlight (in thylakoid)
- Using energy to form ATP and NADPH (in thylakoid)
- Using ATP and NADPH to power synthesis of sugars from CO2 (in stroma).
What are pigments?
They are molecules that absorb photon light energy in the visible range, they are required for photosynthesis. Each pigment has its own absorption spectrum.
What is the most prominent pigment in chloroplasts?
Chlorophyll-a.
How does Chlorophyll-a work?
It possesses a porphyrin ring that uses resonance to channel the photon energy for a few moments.
