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 percentage of the offspring will be tall, Tall (T) plants are dominant...

Tall (T) plants are dominant and short (t) plants are recessive. Two heterozygous tall plants are crossed. What percentage of the offspring will be tall?

Central and peripheral nervous systems, The brain is only a part of a large...

The brain is only a part of a larger nervous system that extends to each part of the body. The nervous system can be divided into central nervous system (CNS), which consists of th

Explain the nutritional management of eating disorders, Explain the Nutriti...

Explain the Nutritional Management of Eating Disorders? Good nutritional management of patients with eating disorders requires attention to a number of areas. It is important t

Explain glomerular filtration in human nephrons, A horticulturist keeps Chr...

A horticulturist keeps Chrysanthemum plants in short-day conditions during long-day season. State its effect on flowering. Specify the role of phytochrome included. Explain glom

Explain about the proteins, Explain about the Proteins? The term protei...

Explain about the Proteins? The term protein (Greek: proleuo- to occupy first place) was first suggested by Berzelius to describe the complex organic nitrogenous substances fou

Explain oligosaccharides, Oligosaccharides Compounds containing 2 to 6 ...

Oligosaccharides Compounds containing 2 to 6 monosaccharides units joined by a glycosidic  linkage.

Symptoms of mitral regurgitation, Q. Symptoms of mitral regurgitation? ...

Q. Symptoms of mitral regurgitation? Symptoms depend upon underlying etiology of mitral regurgitation. Patients with mild mitral regurgitation and most of those with even sever

Determine the nutritional and functional role of bromine, Minerals : Bromin...

Minerals : Bromine                 Food Source       Brominated flour  Nutritional Functional role Not known to be essential to humans. Dough improver: KBrO 3 impr

State long-term benefits of exercise, State four long-term benefits of exer...

State four long-term benefits of exercise. The long-term advantages of exercise are: a) Enhance in size of the muscles used, b) Decrease of heart rate and c)  Enhance

Explain the deficiency and toxicity of vitamin a, Explain the Deficiency an...

Explain the Deficiency and Toxicity of vitamin A? Who defines VAD as tissue concentrations of vitamin A low enough to have adverse health consequences even if there is no evide

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