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

Fowl pox, F o wl pox Fowl pox is a contagious disease of birds, cause...

F o wl pox Fowl pox is a contagious disease of birds, caused by a member of family Poxviridae, characterized by wart-like nodules on the skin and diphtheritic necrotic membra

Show the use of incineration for sterilization, Q. Show the Use of Incinera...

Q. Show the Use of Incineration for sterilization? This is an excellent method for rapidly destroying materials such as soiled dressings, animal carcasses, bedding and patholog

Which does not contain a guanidinium group, Which of the following does NOT...

Which of the following does NOT contain a guanidinium group Select one: a. Urea b. arginine c. creatine d. guanidinium ion

Vegetative development - development, Vegetative Development - Development ...

Vegetative Development - Development The process of growth and differentiation of cells into organs and organisms is often termed development. For example, the development of

Aortic regurgitation by cardiac catheterization, Q. Aortic regurgitation by...

Q. Aortic regurgitation by Cardiac Catheterization? Often cardiac catheterization is not indicated as reliable information for management decision making can be obtained throug

Schizocoelous pattern – coelom, Schizocoelous pattern – Coelom There ...

Schizocoelous pattern – Coelom There are two patterns of coelom formation in animals schizocoelous and enterocoelous. In schizocoelous pattern, two teloblasts cells (primordi

Specify the term in detail - swim bladder, Specify the term in detail - Swi...

Specify the term in detail - Swim bladder. Found in bony fish, this gas-filled chamber is used to main neutral buoyancy. Oxygen in blood is added or removed as required. Swim b

Define the different forms of protein energy malnutrition, Define the Diffe...

Define the Different Forms of Protein Energy Malnutrition? The term PEM is used to describe a wide range of clinical conditions ranging 'from the very clinically detectable flo

Wbc.., Ask question #Minimuwwm 100 words accepted#

Ask question #Minimuwwm 100 words accepted#

How do taenias classify according to the division of sexes, How do taenias ...

How do taenias classify according to the division of sexes? Taenias are monoecious (hermaphrodite), the similar individual has female and male reproductive organs and undergoes

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