Parasitic Nutrition — Definition and Examples

Parasitic Nutrition is a mode of nutrition where an organism (the parasite) obtains its food and nutrition from the body of another living organism (the host) without killing it immediately, but often harming it.

The relationship is: Parasite benefits + Host is harmed = Parasitism (a type of symbiosis)

Based on Location:

• Ectoparasites: Live outside the host's body. Examples: Lice, Fleas, Ticks, Leeches.
• Endoparasites: Live inside the host's body. Examples: Tapeworm (in intestine), Roundworm, Plasmodium (malaria parasite in blood cells).

Based on Dependency:

• Obligate parasite: Cannot survive without host. Example: Plasmodium (malaria).
• Facultative parasite: Can live independently but can also parasitise. Example: Pseudomonas aeruginosa.

• Cuscuta (Amarbel): A leafless, yellow, thread-like plant that twines around host plants (like wheat or tomato) and absorbs water and nutrients through structures called haustoria. It has no chlorophyll and cannot photosynthesise — fully dependent on the host.
• Rafflesia: The world's largest flower — a root parasite on tropical vines.

• Tapeworm: Lives in the human intestine — absorbs digested food through its entire body surface (no digestive system of its own).
• Plasmodium: The malaria parasite lives inside red blood cells.
• Rhizobium: Actually mutualistic (not parasitic) — fixes nitrogen.