Discovery of Cell
Discovery of Cell
Robert Hooke (1665) while examining a thin slice of cork under the primitive microscope, observed that cork consists of small box like structure resembling honeycomb. He called these boxes 'cells'. The substance called cork comes from the bark of a tree. The use of word "Cell" to describe these units is used till today in biology. Cell is a Latin word for 'a little room'. The ordinary compound microscope of today is a greatly improved design of the original Hooke's microscope.
Antony van Leeuwenhoek(1632 - 1723) was an ordinary public official who ground lenses and made microscope observations as a hobby. He examined pond water in 1674, and observed dozens of protists which he called 'animalcules,' as well as Spirogyra or Green algae.
These discoveries helped us to understand different characteristics of cells. Some of these characteristics are :-
In 1838, Matthias Schleiden , a German Botanist, announced that every plant is made up of a large number of cells and each of these cells performed various life processes. A year later, Theodor Schwann, a German Zoologist, made similar discoveries in animals. These discoveries of two different scientists ultimately got published as Cell Theory in `1839.
Rudolf Virchow in 1858 made an addition to the cell theory by saying that all cells arise from pre - existing cells.
According to Cell Theory :-
Which of the following are correct : (a) The cells were discovered by Robert Hooke, English scientist in 1665. (b) The cells were discovered by Robert Brown, English scientist in 1665. (c) Cell have the ability to replicate independently. | |||
| Right Option : C | |||
| View Explanation | |||
Cells were determined to be the basic structural units of plants and animals in which century? | |||
| Right Option : C | |||
| View Explanation | |||
The term protoplasm has been coined by ____________________ . | |||
| Right Option : D | |||
| View Explanation | |||
Students / Parents Reviews [20]
My experience with Abhyas academy is very good. I did not think that my every subject coming here will be so strong. The main thing is that the online tests had made me learn here more things.
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