Causes and spread of infection
Name
UNIT 22
CAUSES AND SPREAD OF INFECTION
1.1 Identify the differences between bacteria, viruses, fungi and parasites
What is a Bacteria?
A bacteria is a 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 off spring 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.
What is a 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
What is a fungus?
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 are the chytrids, which produce flagellated gametes
What is a parasite?
A parasite is an organism that lives
UNIT 22
CAUSES AND SPREAD OF INFECTION
1.1 Identify the differences between bacteria, viruses, fungi and parasites
What is a Bacteria?
A bacteria is a 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 off spring 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.
What is a 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
What is a fungus?
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 are the chytrids, which produce flagellated gametes
What is a parasite?
A parasite is an organism that lives