Short Answer 
Plasmodium is a unicellular eukaryotic parasite that can undergo mutations leading to drug resistance, especially after exposure to treatments like artesunate. This evolutionary process allows resistant strains to survive and reproduce, perpetuating their resistant traits in future generations.
Step 1: Understanding Plasmodium
Plasmodium is a type of unicellular eukaryotic organism that acts as a parasite, primarily infecting insects and vertebrates. These organisms are characterized by their single-celled nature and can undergo various reproductive life cycles, which include both sexual and asexual methods of reproduction. This versatility allows them to thrive in diverse environments.
Step 2: The Impact of Mutation
In specific populations of reproducing organisms, a genetic change known as a mutation can occur, leading to heritable phenotypic changes in their offspring. In the case of Plasmodium, exposure to a drug like artesunate has led to mutations in some strains, making them resistant to treatment. This resistance allows these mutated strains to survive and reproduce, passing on their resistant traits to future generations.
Step 3: Mechanism of Resistance Development
The development of resistance in Plasmodium strains can be explained through the following points:
- Repeated exposure to artesunate increases selective pressure on these organisms.
- Some strains undergo mutations that alter their genetic makeup, enabling them to survive despite the drug’s presence.
- The offspring of these mutated strains inherit the resistance, leading to a population that is increasingly less sensitive to artesunate over time.