Lecture 14 Flashcards
As a plant grows into a tree where does the majority of the biomass come from?
Air
As a baby grows into an adult where does the majority their dry biomass directly come from?
Diet
Chemotrophs
Use chemicals as energy source
Chemoorganotrophs
Organic chemicals
Chemolithotrophs
Inorganic chemicals
Phototrophs
Use light as energy source
What microorganisms are remnants of a primordial metabolism
Archaea
Anoxic
without oxygen
How was the metabolism of primitive cells
-anaerobic
-obtained carbon from CO2 and energy from H2
-chemolithotrophic
Cyanobacteria
Photosystem that use water instead of sulfur to make oxygen
Great Oxidation Event
Causes oxygen levels to rise and many organisms evolved their ability to live on the presence of oxygen
Why can oxygen be toxic?
During aerobic respiration oxygen can be reduced by electrons and form superoxide radicals and hydrogen peroxide which are toxic
True or false: Superoxide radicals and hydrogen peroxide go through the electron transport chain
False
Superoxide and hydrogen peroxide are carried directly by oxygen instead of going through the electron transport chain
How can microbe detoxify toxic oxygen species?
- Superoxide dimutase (SOD): removes superoxide radicals
- Catalase and Peroxidase: removes hydrogen peroxide
True or false: Eukaryotes can make catalase
True