BIOLOGY SSS 2 THIRD TERM

WEEK THREE

PESTS AND DISEASES - DISEASES CAUSED BY FUNGI, BACTERIA AND VIRUS

PERFORMANCE OBJECTIVE

students should be able to;

1. Name one disease each caused by
   1. Virus
   2. Bacteria
   3. Fungi

CONTENT

1. Virus

Viruses are intracellular (inside cells) pathogenic particles that infect other living organisms. Human diseases caused by viruses include chickenpox, herpes, influenza, rabies, smallpox and AIDS (acquired immunodeficiency syndrome). Although these are the viruses most of us are familiar with, the first virus ever described and from which the term was eventually derived was tobacco mosaic virus or TMV (the term virus was derived from the original description of the causal agent of TMV.

Virus particles are extremely small and can be seen only with an electron microscope. Most plant viruses are either rod-shaped or.... View More