Biology

The Meaning of “Waste”

Waste anything which has no useful value to a body at a particular time and/or which there is no excess. Commonly in everyday life, anything which no longer has any use and is simply cluttering up an area is considered as waste or garbage.

Some forms of matter can be useful to a body at one time and of no value or even harmful at another time. Depending on whether their dominant activities are photosynthesis or respiration at certain times, green plants could be alternation in their manner of using each of these gases as a nutrient or as a waste. Excess water in plants or animals bodies is also treated as waste.

Plant and animal body wastes originate or accumulate from two general types of actions:

    • Internal metabolic processes, where energy is converted from one form to another or where body parts are either built up or broken down, result in waste products.
    • Ingestion of nutrients can bring in excess amounts of the nutrients themselves or of other substances combined with those nutrients but not needed or utilized ''   such as the extra amounts of fibre or cellulose which we may consume with our plant foods.

Waste Substances

    • Gases released by the processes of photosynthesis and respiration: oxygen and carbon-dioxide.
    • Water, as a byproduct of respiration or as an excess of ingestion.
    • Mineral salts, such as those of sodium chlorine and potassium.
    • Ammonia or nitrogen products, primarily from cellular respiration involving proteins.
    • Excess organic substances ingested into bodies, such as cellulose or vitamins.
    • Parts of cells or tissue which are no longer functioning, such as plant bark, animal skin or red blood cells.

The Importance of removing wastes

Allowing wastes to accumulate either inside cells or in the fluids around the edges could be detrimental in a number of ways. At the cellular levels, such accumulations could slow or even stop the processes of diffusion,...