Describe The Differences In The Nutritional Requirements Of Microorganisms

7.1 Microbial Nutrition The process by which microorganism acquire the nutrients from their environment and use them in metabolism and growth is called nutrition. There is not much difference in the nutrition of humans and microorganisms. All living things require a source of element like sulfur, carbon, oxygen, etc. There are some essential nutrients, those are the elements that must be provided to the organisms. Some those are required in large quantity called macronutrients and some are required in small amount those are called micronutrients. The nutritional requirements of the microorganisms can be determined by their chemical composition of the cell.

All the nutrients obtained by the microorganisms come from the naturally existing elements.

Phosphorus is mainly obtained from phosphate that comes from the rocks and mineral deposits. Sulfur can be obtained from rocks and sulfur gas. It plays a big role in building the amino acids and vitamins. There are many other important elements that are required by the microbes like potassium, calcium, zinc, etc. we can also subdivide the bacteria also by the method in which they gain energy. The bacteria that gain energy by photosynthesis are called phototrophs and the bacteria that gain energy from chemical compound are called chemotrophs.

Autotrophs-

There are two types of autotrophs photoautotrophs and chemoautotrophs. Photoautotrophs derive their energy by the process of photosynthesis and Chemoautotrophs derive their energy by chemical reactions with the chemicals from the environment.

Heterotrophs-

Heterotrophs commonly derive energy from organic compounds. They break down these organic molecules by respiration or fermentation. There are two types of chemoheterotrophic organisms :Saprobes- they live on the dead organisms and Parasites- live and depend on the living

The speed of diffusion depends upon the temperature and the concentration gradient. Diffusion of water from its higher concentration to lower concentration is called Osmosis. Water molecules can move through the permeable membrane in cell towards the concentration gradient. Due to the difference in the concentration of inside and outside we can distinguish them by terms isotonic, hypotonic and hypertonic. Microorganisms have adapted to the osmatic variation. Bacteria that lives in hypotonic water has to face continuous flow of water into the cell to avoid bursting they have developed a cell