Ribosomes, Biology

Assignment Help:

Ribosomes:     are minute nonmembranous  and dense spheroidal particles or  granules. First observed by   electron   microscopy by palade 1955. Being only about 200 to 250 a in diameter these are smallest, but most abundant of all cytoplasmic organelles. Every cell contains several thousands to millions of ribosomes. Most  of these  are linked  at the surface of endoplasmic reticulum  many  are free  in   the cytosol, and some  are found in the   in the nucleus and mitochondria  also  in  chloroplasts  of plant cells.

Structurally. Each ribosome has two parts a proximal larger subunit linked to the endoplasmic are composed of RNA and proteins approximately in equal amounts. The ribosomal RNA  ( rRNA)   has only four macromolecules .  Three in the larger subunit  and one the  smaller subnuits.   Considerable portion of these RNA molecules secondarily become  double stranded due to intermolecular the intermolecular base  pairing  so that  the molecules become 3 dimensional .The ribosomal protein   include 73 macromolecules 40 in  large in 33 in small subunits .

Ribosomal  subunits  are assembled from  their  component  r RNA  and protein  molecules  in the nucleolus of nucleus. These  are of the four r RNA  molecules are  synthesized  in the nucleolus . The   fourth is   synthesized by some chromosome outside the nucleolus. This and the 73 protein molecules synthesized in the cytoplasm migrate to the nucleolus for being incorporated in ribosomal subunits. The latter diffuse out into the cytoplasm and assemble to form ribosome's most of which link the endoplasmic reticulum.


Related Discussions:- Ribosomes

Explain the technology of transgenic plant, Explain the technology in which...

Explain the technology in which transgenic plant was constructed in which seeds that will produce plants for a single crop.

Precautions for determination of iodine number of lipids, Precautions for d...

Precautions for determination of iodine number of lipids? 1. If using the pipette for transferring the oil, allow the pipette to drain slowly and completely, as oil takes time

Define assessment of selenium status, Define Assessment of Selenium Status?...

Define Assessment of Selenium Status? Blood glutathione (GSH) peroxidase activity is directly related to blood selenium up to a level of 1.27 μmoles/L. Beyond this point, the a

Programmes directed towards the common crop plants, Programmes directed tow...

Programmes directed towards the common crop plants These programmes can be directed towards incorporating the following traits among common crop plants. Non-photo

What is the life duration of the red blood cells, Q. On average what is the...

Q. On average what is the life duration of the red blood cells? Where are they destroyed? What is the destination of the heme groups after the destruction of hemoglobin molecules?

How would contrast single covalent bonds, 1. In modern blimps, the gas of c...

1. In modern blimps, the gas of choice used to inflate them is helium rather than hydrogen. Hydrogen would be lighter, but helium is safer. Compare and contrast the atomic structur

Explain the principle or theory of biuret method, Explain the Principle or ...

Explain the Principle or Theory of biuret method? If a strongly alkaline solution of Biuret is heated with very dilute copper sulphate, a violet colour is obtained. The substan

Define the blood coagulation - function of vitamin k, Define the Blood coag...

Define the Blood coagulation - Function of Vitamin K? The primary function of vitamin K in the body is in the maintenance of normal blood coagulation. The vitamin K-dependent c

In which condition number of white blood cell decreases, The condition in w...

The condition in which there is a DECREASE in the number of white blood cells in humans is termed as: a) Leukocytosis (pron: lew-kO-sigh-toe-sis) b) Leukopenia (pron: lew-kO

What is in a test cross invovle, In a test cross: A.alleles of two genes is...

In a test cross: A.alleles of two genes is always involved. B.One parent must be homozygous recessive C.the physical manifestation of a trait can be deterimined. D.both A and C are

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd