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 protein deficiencies in nutritional care, Explain Protein Deficienc...

Explain Protein Deficiencies in Nutritional Care? A depleted amino acid pool leads to poor wound healing (dehiscence), delayed healing of fractures, anaemia, depressed pulmonar

Responses of plants to stress, Responses of Plants to Stress You know ...

Responses of Plants to Stress You know that certain plant species can grow in severe environmental extremes. For example, plants grow below 0°C in the Himalayas and above 45°C

Method of cloning dna fragments into plasmids, During our discussion of rep...

During our discussion of replication origins we took a step-by-step look at the method of cloning DNA fragments into plasmids . Based on your knowledge of this discussion which

Define precautions for estimation of vitamin c in chillies, Define Precauti...

Define Precautions for Estimation of Vitamin c in Chillies? 1. Rinse all glassware with 3% metaphosphoric acid before you begin your practical and subsequently each time you wa

Why this stain have an affinity, Giemsa stain is a basic stain, thus the ma...

Giemsa stain is a basic stain, thus the major chromagen is positively charged (cation). Why does this stain have an affinity for the bacteria cell wall, and for certain cellular co

Pisces, what is the mode of nutrition in pisces

what is the mode of nutrition in pisces

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?

Factors that affects oxygen dissociation curves, Factors that affects Oxyge...

Factors that affects Oxygen Dissociation Curves Oxygen dissociation curve for a sample of blood is affected by several factors. The most important of them are: Te

Haematology, differenciate between plasma and serum

differenciate between plasma and serum

Surface run-off - causes of water pollution, Surface Run-off - Causes of Wa...

Surface Run-off - Causes of Water Pollution The surface run-off from cultivated lands where inorganic fertilisers, pesticides, insecticides and rich manure are applied and sol

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