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

What is bidirectional superior cavopulmonary shunt, What is Bidirectional S...

What is Bidirectional Superior Cavopulmonary Shunt-Bidirectional Glenn Shunt ? Hospital mortality is between 5 and 10 per cent. Early palliation is very good with arterial sat

What is an erlenmeyer flask and how is it used, What is an Erlenmeyer flask...

What is an Erlenmeyer flask and how is it used? It is same to a beaker, except that it gets narrower at the top. It is use to hold liquids and do reactions in it.

List the four phases of meiosis i, List the four phases of meiosis I, and b...

List the four phases of meiosis I, and briefly explain what occurs during each phase Prophase I: DNA coils into chromosomes, the nucleolus and nuclear envelope disappear, the m

How to derive a mathematical equation, A microbiology student isolated a hy...

A microbiology student isolated a hypothetical bacterial cell that seems to quadruple every generation. Knowing that binary fission is an exponential function, derive a mathematica

What are the so-called good and bad cholesterol, What are the so-called "go...

What are the so-called "good" and "bad" cholesterol? Lipoproteins are complexes made of lipids (triglycerides and cholesterol) and proteins. The lipoproteins present dissimilar

Fruits why not glucose, Sucrose is commonly used to preserve fruits why not...

Sucrose is commonly used to preserve fruits why not glucose? Ans) Glucose is reactive due to its open-chain form having an aldehyde group.

Nervous tissue and its components, NE R V OU S TISSUE The nervous...

NE R V OU S TISSUE The nervous tissue in general develops from the ectoderm of the embryo, but the microgliocytes. It does not have a matrix. The special properti

Reproduction, REPRODUCTIO N - It is not only production of new ones...

REPRODUCTIO N - It is not only production of new ones to increases its number but a means for the survival of a population on earth. Main aim is "survival and continuati

Explain the heart rate monitoring (hrm) method, Explain the Heart Rate Moni...

Explain the Heart Rate Monitoring (HRM) Method? HRM is a method to measure the daily energy expenditure of free-living individuals, based on the relationship of heart rate and

Procedures for diagnosis - restriction enzyme analysis, R e striction...

R e striction enzyme analysis: The restriction endonuclease analysis of viral DNA fragments or DNA fingerprinting discovered in 1970s has revolutionized the study o

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