BIOLOGICAL AGENTSR. Fuster - I.E.S. Isidor Macabich

• Biological agents are microorganisms that cause diseases. They are also called pathogens.

• Microorganisms means that we can’t see them with the naked eye. We need a microscope.

BIOLOGICAL AGENTS ARE:B

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VIR

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VIRUS (sing) / VIRUSES (pl.)

• A virus (from the latin meaning toxin or poison), is a microscopic infectious agent that is unable to grow or reproduce outside a host cell.

• Viruses infect all cellular life forms and are grouped into animal, plant and bacterial types, according to the type of host infected.

TYPES OF VIRUS

WHAT IS A VIRUS LIKE?

• Each viral particle, or virion, consists of genetic material, DNA or RNA, within a protective protein coat called a capsid.

• The capsid shape varies from simple helical and icosahedral (polyhedral or near-spherical) forms, to more complex structures with tails or an envelope.

Diseases caused by viruses include:

• influenza (flu)

• Colds

• Measles

• Mumps

• Rubella

• chicken pox

• AIDS

BACTERIUM (sing.)/ BACTERIA (pl.)

• Bacteria are a group of unicellular microorganisms

• They are prokaryotic cells included in the Kingdom Monera

TYPES OF BACTERIA

They come in many shapes and sizes, but even the largest are only 10 micrometres long (10 millionths of a metre).  

Bacteria have a wide range of shapes, ranging from spheres to rods and spirals.

WHAT IS A BACTERIUM LIKE?

Bacteria are living cells and, in good conditions, can multiply rapidly. Once inside the body, they release poisons or toxins that make us feel ill.

• Diseases caused by bacteria include:  

• food poisoning

• Cholera

• Typhoid

• whooping cough

• gonorrhoea (a Sexually Transmitted Disease)

A white blood cell ingesting disease-causing bacteria

PROTOZOAN(sing) / PROTOZOA(pl.)

• The name 'protozoa' is used for single celled organisms like amoebas and ciliates.

• They are unicellular eukaryotes included in the kingdom Protoctists

TYPES OF PROTOZOA

MALARIA

FUNGUS (sing.) / FUNGI (pl.)

• A fungus is a eukaryotic organism that is a member of the kingdom Fungi.

• The fungi are heterotrophic organisms

• The kingdom Fungi includes

mushrooms , mould

and yeast .

Athlete's foot, also called Tinea Pedis, is a parasitic fungal infection of the epidermis of the human foot.

The term "athlete's foot" refers to the disease and not the organism (fungus)

Trichophyton

…And if you want to know more…www.sdnhm.org/.../teachers/background.html

Or play a game...”Bacteria in cafeteria”

http://www.amnh.org/nationalcenter/infection/02_bac/02_bac.html