• Question: How do these parasites work inside another organism,and what are their functions?

    Asked by ILuvScience to Franco on 13 Jun 2016.
    • Photo: Franco Falcone

      Franco Falcone answered on 13 Jun 2016:

      Hi ILuvScience
      every parasite is different, they target different organs. Many parasites live in the gut, which gives them easy access to food. But other parasites live in the red blood cells (malaria) or in white blood cells, or the brain, or the lung, or in dogs, the heart. Their function is to make sure that they live and carry on doing so, but such a relationship can change over thousands of years and they can become so used to each other, that none can survive without the other , in which case it is called symbiosis. For example, in your cells, you have mitochondria, which used to be little bacteria, and some parasites have bacteria inside them called Wolbachia, which they also need to live.

Comments

  • Photo: Claire

    Claire commented on :

    That’s a great answer from Franco. I totally agree – there are loads of different parasites and for each parasite there is a different function. A basic definition of a parasite is an organism (the parasite) that lives off another organism (the host) using up its resources but not providing any obvious benefit to the host. Parasite comes from a Greek word meaning ‘to eat at another’s table’; like a dinner guest who never helps with the cooking!

    It’s cheating a little bit, but I’ll tell you about my favourite parasite as an example of how a parasite can function. Schistosomes are parasitc worms that live in the blood stream of their host. They feed off of nutrients in the blood (just like the unwanted dinner guest!) and being inside the host protects them from predators and challenges of living in the outside world. To establish infections, young schistosomes burrow through the skin of their host and migrate to the blood stream. To make new parasites, adult worms in the blood lay eggs that are shed in poo or urine. Schistosomes are particularly clever because, even though they live inthe blood where there are lots of immune cells that could attack them, they can often manage to avoid being killed and live there for a very long time (several years in average).