Unit Ic02

UNIT IC02
Outcome 1
1.1
Bacteria
Bacteria are living things that are neither plants nor animals, but belong to a group all by themselves. They are very small--individually not more than one single cell--however there are normally millions of them together, for they can multiply really fast. Bacteria are prokaryotes (single cells that do not contain a nucleus).
Every species has a great ability to produce offspring and its population expands until it runs out of food or it is limited by competition, its own waste products, or some other factor. Changes in climate or introduction of a new species from elsewhere can greatly affect the balance of nature.
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Most viruses are too small to be seen directly with a light microscope. Viruses infect all types of organisms, from animals and plants to bacteria and archaea.
All viruses have genes made from either DNA or RNA, long molecules that carry genetic information; all have a protein coat that protects these genes; and some have an envelope of fat that surrounds them when they are outside a cell.
Fungi
These are Eukaryotes. When compared to bacteria (prokaryote) and virus. Like plants and animals, fungi are eukaryotic multicellular organisms.
One major difference is that fungal cells have cell walls that contain chitin, unlike the cell walls of plants, which contain cellulose. The chitin adds rigidity and structural support to the thin cells of the fungus, and makes fresh mushrooms crisp
Most members of the kingdom Fungi lack flagella; the structures are completely absent in all stages of their life cycle. The only exception is the chytrids, which produce flagellated gametes.
Parasites
A parasite is an organism that lives on or inside another organism to the detriment of the host organism.
These are of various forms and types. A parasite is an organism that lives on or in a host and gets its food from or at...