i don't really know but i think they give you hygiene
you can help plants by not plucking them,you can help plants by watering them.you can help animals by feeding them,sheltering them, if they are lost giving them to the police.etc!!!!!!!!!!!
Oxygen is an end product of photosynthesis, along with glucose/starch, and is needed for humans and other living things, besides plants.
plants excrete by giving out oxygen
oxygen
The oxygen that plants make is taken up by humans. The humans take the oxygen and transform it into carbon dioxide. When the humans do this then the plants take it and change it back into oxygen. This is a never-ending cycle, without plants, humans and animals would die out, without humans and animals, plants would die out.
oxygen
oxygen
Plants supply food and oxygen for animals and humans.
Many other organisms besides humans produce epinephrine. It is found in some plants, insects and mammals.
if there is no plants humans cant get oxygen so naturally people cant exist on earth
Oxygen.
Oxygen is a gas that does not naturally replenish itself in the atmosphere and requires the work of photosynthesizing plants to replenish it. Humans breath oxygen that plants produce and the plants breathe the carbon dioxide that humans produce.