I'm not sure if this is exactly correct, but to complete photosynthesis, plants need carbon dioxide and water. Usually sunlight as well. If you are supposed to be specific, you could put H2O. I hope I answered your question!
Abiogenesis is another name for spontaneous generation.
Answer AND Explanation:
As light reflected from an external object enters the eye, it is refracted by the cornea, aqueous humour, the lens and vitreous humour so that an image is focused on the retina. The image is real, upside down and smaller than the object. The photoreceptor cells are stimulated by the reflected light and impulses are set off. The impulses are transmitted by neurons through the optic nerve to the optic region of the brain. The brain interprets the impulse as an upright impression of the object.
Answer:
From what I remember in my 9th grade biology class, it's usually half that amount.
