In photosynthesis, energy of the sun is used to change carbon dioxide and water into:

trace elements
nitrogen and oxygen
oxygen and sugar
potassium and phosphorus

the menstrual cycle – higher tier. negative feedback mechanisms affect the production of hormones in the menstrual cycle. oestrogen also stimulates the release of lh (luteinising hormone) from the pituitary gland, which in turn controls the production of progesterone.

frogs. the lower the ph the higher the acid content. frogs have the highest tolerance in this scenario.