Question

Ribosomes were discovered under E.M. by
A. Golgi
B. Porter
C. De Robertis
D. Palade

Answer 1

Hint: Ribosomes are the cell organelles that means they are the organs of the cell and found inside the cell. They are the minute particles and are also called protein factories because their function is to synthesise a variety of proteins.

Complete Answer:
Ribosome:
- Ribosome is a complex molecule which is made up of ribosomal RNA molecules and proteins.
- Romanian-American cell biologist named George Emil Palade discovered the ribosomes under E.M. (electron microscope) in 1955.
- Palade was awarded the Nobel prize in 1974 for his work.
- Ribosomes are present inside the cell floating in the cytoplasm. They may be freely present or may be attached to the Endoplasmic Reticulum.
- Each ribosome has two subunits – a smaller subunit and a large subunit. Both these two subunits together form a unit called a ribosome. Each of these subunits contain the rRNA (ribosomal RNA).
- Ribosome is responsible for translating the mRNA (messenger RNA) molecules to form the proteins from the amino acids with the help of tRNA (transfer RNA).
- Ribosomes are present in both the prokaryotic (those cells which do not have well defined nucleus) and Eukaryotic (those cells which have well defined nucleus with nuclear membranes) cells.
 Eukaryotes have 80s ribosomes while prokaryotes have 70s ribosomes.

Additional information:
A. Golgi – Camillo Golgi first discovered the golgi apparatus or golgi complex in the cell.
B. Porter – Porter was a biologist who made the first photograph of tissues with the help of an electron microscope.
C. De Robertis – De Robertis was the American embryologist whose work has contributed to the discovery of molecular mechanisms of embryonic inductions.
Therefore, it has been clear from the above discussion that Ribosomes were discovered under E.M. by Palade.

Hence, option D is the correct answer for this question.

Note: Proteins are too essential for the proper functioning of the body. These are only made by ribosomes without ribosomes; these can’t be made. The ribosomes can also be seen in the Chloroplasts and Mitochondria of the Eukaryotic cells.