There are trillions of cells EVERYWHERE including blood cells, brain cells, and even skin cells !! I believe that multicellular organisms that are large need to have trillions of cells to be able to fill their whole body. For example , humans, Humans have one of the most complex cells, we humans are very big so thousands of cells would not be enough to contain our entire body. Even the word ' multicellular' meaning multiple cells gives people a hint that we are multicellular . In conclusion , trillions of cells are needed for multicellular organisms , without them we wouldn't be able to function properly.
Gonads are the body structures that produce sex cells. Sperm are the male sex cells. Eggs are the female sex cells. Chromatin are threadlike DNA found inside the sex cells.
In 1884, Hans Christian Gram described a method of staining bacterial cells while not staining surrounding animal tissues. However, he thought that the staining method he developed was faulty because not all bacteria stained. ... Not all bacteria stained because some have walls that prevents the staining.
