<h3><u>Answer;</u></h3>
Parasitic relationship
<h3><u>Explanation</u>;</h3>
- A parasitic relationship is a type of relationship in which one organism, the parasite, lives off of another organism, the host, harming it and possibly causing death.
- The organism that is harming the other one is called a parasite. Examples of Parasitism includes fleas or ticks that live on dogs and cats are parasites.
- In this case; the organism that lives in the gills of a fish consuming fish's blood is the parasite, while fish is the host.
<span>Anton van Leeuwenhoek learned to grind lenses ( 1668) and develop simple microscopes.
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Leeuwenhoek heated the middle of a small soda glass rod , over a flame. On pulling apart the two ends, the glass rod elongated into thin whiskers .
Heating the end of this whisker resulted in a tiny high quality glass sphere. These glass spheres then became the lens of his microscope, with the smallest sphere providing the greatest magnification.
Leeuwenhoek's designs were very basic. The body of the microscope was a single lens mounted in a tiny hole on a brass plate. The specimen was then mounted on a sharp point that sticks up in front of the lens. It's position and focus could be adjusted by turning the two screws.
The entire instrument was about 3 to 4 inches long and had to be held up close to the eye, requiring good lighting and great patience to use.
