<span>Anton van Leeuwenhoek learned to grind lenses ( 1668) and develop simple microscopes.
</span>
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.
Is this multiple choice?!
<span><span>Photoreceptors
are cells</span><span><span> <span>in
the retina</span></span><span> that
begin the process of seeing. The retina is the back part of the eye that
contains the cells that respond to light. These specialized cells are called photoreceptors. They
absorb and convert light into electrical signals. These signals are sent to
other cells in the retina and ultimately through the optic nerve</span></span><span> <span>to
the brain</span></span><span> where
they are processed into the images we see. The answer is true. Animals
with photoreceptors have good vision.</span></span>
Answer:
it gives a greater variety of crops
