Parasitism is a type of relationship in nature where one organism benefits and the other is harmed.
It is a form of symbiosis (close biological interaction between two organisms).
Definition
Parasitism is when a parasite lives on or inside a host and gets food or shelter, while the host is harmed but usually not immediately killed.
Key terms
- Parasite → the organism that benefits
- Host → the organism that is harmed
Examples of parasitism
1. Humans and lice
- Lice live on the scalp and feed on blood
- Causes itching and irritation
2. Tapeworm in humans
- Lives in intestines
- Absorbs nutrients from food
3. Mosquitoes and humans
- Mosquito feeds on blood
- Can spread diseases like malaria or dengue
4. Plants (mistletoe)
- Grows on trees and takes water/nutrients
- Weakens the host tree
Types of parasites
- Ectoparasites → live on the surface (lice, fleas)
- Endoparasites → live inside the body (worms, protozoa)
Important features
- Parasite benefits, host is harmed
- Usually does not kill host immediately
- Often highly adapted to survive in or on host
Difference from other relationships
- Mutualism → both benefit
- Commensalism → one benefits, other unaffected
- Parasitism → one benefits, other harmed
Bottom line
Parasitism is a natural survival strategy where one organism depends on another at the expense of its health or resources.
If you want, I can also explain real human parasites and how infections are prevented in daily life.
