Question

How would a scientist have made the distinction between a unicellular and a multicellular organism in the 17th century (1600s), the mid-20th century (1900s), and in the 21st century

Answer 1

Ans.

Unicellular organisms are those organisms that are made up of a single cell, while multicellular organisms are made of up more than one cell. During 17th century, a scientist could distinguish between an unicellular and a multicellular organism by using simple microscope, developed by Antony Van Leeuwenhoek. In the mid-20th century and 21st Century, a scientist could make distinction between unicellular and multicellular organisms, by using advance microscopy techniques, such as electron microscopy and electron microscopy.

Answer 2

Antony Van Leeuwenhoek invented the first microscope that could see cells. So, in the 17th century, a simple microscope must have been used to see the cells and distinguish between them.

The 20th century saw a development in the field of microscopy. Microscopes like phase contrast microscope developed by Frits Zernike and transmission electron microscope invented by Ernst Ruska and Max Knoll  were used for many purposes.

In the 21st century, microscopes like digital and stereo microscopes are used.