Types of Ribosomes
The ribosomes present in eukaryotic cell is 80S whereas in prokaryotic cell 70S ribosomes are found. The ‘S’ (Svedberg’s Unit) here stand for sedimentation coefficient. It is indirectly used as a measure of density and size. The 70S and 80S are both made up of two subunits.
70S Ribosomes |
80S Ribosomes |
|
These are found both in prokaryotes and eukaryotes. |
They occur in eukaryotic cells. |
| They are found freely inside the cytoplasm of prokaryotes and matrix of plastids and mitochondria of eukaryotes. | They are found inside the cytoplasm of eukaryotes either freely or attached to ER. |
| The sedimentation coefficient is 70. | The sedimentation coefficient is 80. |
| They are comparatively smaller in the length of (200—290 A) and diameter of (170— 210 A). | They are larger in the length of (300—340 A) and breadth (200—240 A). |
| They are lighter, 2.7—3.0 million Daltons. | They are heavier, 4.0—4.5 million Daltons. |
| The two subunits are the 30S and 50S. | The two subunits are the 40S and 60S. |
| They are synthesized in the cytoplasm of prokaryotes and matrix of semi-autonomous cell organelles. | They are synthesized inside the nucleolus. |
| It contains about 55 protein molecules, 34 in the larger subunit and 21 in the smaller subunit. | It contains about 73 protein molecules, 40 in the larger subunit and 33 in the smaller subunit. |
| The ribosomes contain more rRNA than protein (60:40). | The ribosomes possess less rRNA as compared to protein (40: 60). |
Ribosomes
Ribosomes are cellular structures responsible for translating genetic information from mRNA into functional proteins. Ribosomes are made up of ribosomal RNA (rRNA) and proteins. They are the site of protein synthesis. The ribosome structure consists of two subunits, a small subunit and a large subunit, each composed of ribosomal RNA (rRNA) molecules and proteins. In this article, we will cover ribosomes class 11 notes, the different types of ribosomes and their function.
Table of Content
- Ribosome
- Function of Ribosomes
- Types of Ribosomes
- Conclusion – Ribosome
- FAQs on Ribosome