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Floaters’ are caused by tiny fragments of cell debris within the vitreous humour of the eye – that’s the gelatinous substance between the retina and the lens. Despite the name, they do in fact sink slowly, so they tend to collect near the centre of your field of view when you lie on your back.

Types of Microscopes

• The light microscope. The common light microscope used in the laboratory is called a compound microscope because it contains two types of lenses that function to magnify an object.
• Other light microscopes.
• Electron microscopy.

When viewed, amoebas will appear like a colorless (transparent) jelly moving across the field very slowly as they change shape. As it changes its shape, it will be seen protruding long, finger like projections (drawn and withdrawn).

A tiny blob of colorless jelly with a dark speck inside it—this is what an amoeba looks like when seen through a microscope. The colorless jelly is cytoplasm, and the dark speck is the nucleus. Together they make up a single cell of protoplasm, the basic material of all living things.

After pouring the media into small culture dishes or a large jar, add two rice or wheat grains per 50 mL of Amoeba culture to encourage the growth of the bacteria. Small ciliates feed on the bacteria, and the Amoeba feed on the ciliates.

Most of the free-living freshwater amoebae commonly found in pond water, ditches, and lakes are microscopic, but some species, such as the so-called “giant amoebae” Pelomyxa palustris and Chaos carolinense, can be large enough to see with the naked eye.

Pseudopod comes from the Greek words pseudes and podos, meaning “false” and “feet” respectively. They are projections of the cytoplasm of unicellular protists or eukaryotic cell membrane. The cytoplasm fills the lamellipodium to form the projections, or the pseudo.

Compound microscopes