Chapter 8.4 - Photosynthesis challenges Flashcards
How does reactive oxygen species come about? Why are they dangerous to photosynthesis?
When there is more electrons than what NAP+ can reduce reactive forms of oxygen is created either by:
1. a transfer of absorbed light from antenna chrlophyll to oxygen
2. By a transfer of electron negative oxygen
How could malfunction in the calvin cycle cause damage into cells?
anything that effects thet production of NADPH coulf cause damage or an excess of light
How do cells adapt when Calvin cycle light absorption is low?
- They produce chemicals that detoxify reactive oxygens. high concentration in the chloroplasts. USUALLY BRIGHT COLORS
- Stop the creation of highly reactive oxygen.
Xanthophylls are yellow pigments that slow the formation of reactive pigments. They absorb light and turn it into heat
What is a oxygenese?
an enyzme that adds oxygen to another molecule
What happends when rubisco adds oxygen instead of carbon dioxide to RuBp?
It produces only 1 3-PGA molecules and a 2-PGA molecule. Which cannot be used by the calvin cycle
What is photorespiration?
After recycling some of the 2-PGA carbons into the Calvin cycle the remainder is released back as carbon dioxide. And it consumes ATP.
Why is rubisco so slow?
they are high selective molecules. Ratio for selecting carbon dioxide instead of oxygen 80:1