Carbon dioxide.
Carbon dioxide (CO2) is a waste product produced by animals (including humans of course) during respiration. Plants use this as part of the process of photosynthesis, which in turn creates oxygen (as a waste product).
Oxygen
Carbon dioxide :)
can be used for photosynthesis
Plants need Water (H2O) and Carbon Dioxide (CO2) to produce glucose - which is used as food. The hydrogen (H2) part of the water is used with the carbon dioxide to produce glucose, the food. The remaining oxygen (from the water) is waste.
sludge.
A rather vague question. If you are asking about gases then perhaps the answer you seek is oxygen (produced by photosynthesis in plants) which is used by animals (and plants) for respiration. It would be equally valid to suggest water as the answer. For carnivorous animals, birds and insects could be the answer.
The food produced by plants during photosynthesis is used as a source of energy for the plant's growth and metabolism. This stored energy can also be used by other organisms that consume plants for their own survival. Additionally, some of the food produced may be stored in the form of starch for later use by the plant.
Aquatic plants help to oxygenate the water - replacing the oxygen that's used by the fish - and the decaying fish waste.
a waste gas createdby cells. Used by plants to survive
Carbohydrates serve as a primary source of energy for both plants and animals. In plants, carbohydrates produced during photosynthesis provide energy for growth and reproduction. In animals, carbohydrates from food are broken down into glucose, which is used for energy production in cells.
Nicotine is an alkaloid produced by plants, particularly by tobacco plants. It affects the nervous system of animals. It can be used as an insecticide also.
There are a handful of waste products that are products of a plant's respiration. Oxygen is one such waste product.