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Robert Hooke is most known for discovering the law of elasticity, inventing the term "cell" to refer
to a basic unit of organisms, and studying microscopic fossils. Hooke noticed little boxlike
cavities while observing, which he sketched and characterized as cells. Plant cells had been
found by him. The finding of Hooke led to the recognition of cells as the tiniest units of life. Other
discoveries and observations include Hooke's Law, a solid-body elasticity law that defined how
tension increases and decreases in a spring coil and the tiny structure of cork tree bark. He found
and called the cell as a result of this.
In the late 16th century, Hans and Zacharias Janssen found that putting a lens at the top and
bottom of a tube and looking through it magnified objects on the other end, and they built the first
so-called compound microscope. Scientists were able to observe cells, germs, and a variety of
other structures that were too small to see with the human eye thanks to the invention of the
microscope, I t provided them with a direct insight into the world of the incredibly small.
Genetics is the study of how an organism changes from generation to generation. The process of
genetic engineering necessitates the mixing of genes. Microscopes are vital in genetics because
genes are even smaller than cells. Biology would not have progressed as far as it has without the
microscope, and many diseases would still be curable.
How does it work?
Consider the two lenses in succession on the microscope in the figure to observe how it
generates an image. The object is just beyond the objective lens's focal length, resulting in a true,
inverted image that is larger than the object. The second lens, or eyepiece, is used to focus on the
first image. The eyepiece is positioned so that the objective's initial image is visible. The virtual
image formed by the eyepiece is magnified. The final image is still inverted, but it is farther away
from the observer than the item, making it easier to see.