 |
|
According to site of attack
According to the period of parasitism in the host body.
Host – parasite interactions:
When the body is attacked by a parasite, one of 3 probable interactions take place:
|
|
| ||||||
Parasites get into the host through :
| a- In animals 1- Swallowing food (Ascaris, typhoid) 2- The human skin (Bilharzia, Ankylostoma) 3- The respiratory tract (Viruses, bacteria). 4- The reproductive organs (Syphilis–Gonorrhea) | b- In plants 1- Through natural openings (stomata of leaves) 2- Through any cut in the plant. |
Viruses parasitize all kinds of living organisms including bacteria.
Bacteriophages are viruses that parasitize bacteria.
- As the organism becomes more developed, its chance to be parasitic decreases and vice versa.
Some organism that parasitize human causing diseases.
| Name | Classification | Disease |
| 1. Entamoeba histolytica | Protozoa (Sarcodina) | Amoebic dysentery |
| 2. Plasmodium | Protozoa (Sporozoa) | Malaria |
| 3. Trypanosoma | Protozoa (Flagellata) | Sleeping disease |
| 4. Leishmania | Protozoa | Oriental sore |
| 5. Liver flukes (fasciola) | Flat worms (trematodes) | Liver inflammation |
| 6. Bilharzia worms | Flat worms (trematodes) | Bilharziasis |
| 7. Tape worm | Flat worms (cestodes) | Anaemia |
| 8. Ascaris | Nemathelminths (round worm) | Anaemia |
| 9. Ancylostoma | Anaemia | |
| 10. Oxyuris | Anaemia | |
| 11. Filaria | Elephantiasis |
G.R. Parasitism is less common in plants
Plants are autotrophic preparing carbohydrates through photosynthesis.
The following are parasitic plants that don't contain chlorophyll.
a.Orbanche à (host: Bean).
b. Cascuta à (host: Clover).
c.Mistle toe à (host: Pines)
Saprophytes
Saprophytes secrete digestive enzymes to break complex food in dead bodies & absorb them.
Importance of saprophytes to the environment:
 | |||
 |