ecology !急!

1. During daytime, oxygen is plentiful because plants can use sunlight for photosynthesis. One of the products produced is oxygen. At nighttime, no photosynthesis occurs so there is less oxygen in the water. Plants must then compete for oxygen at night.

2. During waste water treatment, bacteria and other microorganisms break down components in wastewater into simpler and more stable forms of organic matter. Non-organic matter also settles into sludge. It's therefore rich in organic compounds and mineral and serve as great fertilizer

3. Putrefying bacteria are anaerobic bacteria that decomposes protein.
Saprophytic bacteria are aerobic organisms that decomposes organic matter.

4. Fungi and algae can have a symbiotic relationship and form Lichen. Fungi can absorb minerals from rock and nitrogen from the air and also attach themselves firmly to rocks. Algae can then anchor themselves to the fungi and take in the minerals from the fungi. In return, the fungi can benefit from the photosynthesis ability of the algae.

5. No urea in urine is not food for bacteria. Ammonium is food for bacteria

6. Anaerobic bacteria does not require oxygen for growth and may even die in its presence. Aerobic bacteria requires oxygen for growth and may even die in its absence.