Peroxisomes and glyoxysomes, Biology

Assignment Help:

PEROXISOMES AND GLYOXYSOMES

Certain small ovoid  unit membrane bound  sac like  cytoplasmic  organelles, resembling  lysosomes in size  and appearance  were  isolated  from various types of animals  and plant cells  by due Duve 1965 these however differ from  lysosomes in being  formed  by budding  from smooth endoplasmic   reticulum and containing not hydrolysing but mainly certain oxidative enzyme oxidases. D amino  acid oxidase and  urate  oxidase .These  enzyme  catalyse  oxidation  of amino uric and  lactic acids  to synthesize  hydrogen  peroxide (H2O2) and  catalase  enzyme  which  decomposes H2O2 .That  is why these organelles  were  christened peroxisomes  probably these correspond  to microbodies  detected carlier 1954 Rhodin   by electron  microscopy.  Later  it was  found that  some peroxisomal  enzyme are related to the biosynthesis  of certain components  of cellular membranes .In  plant cells  peroxisomes co operate with chloroplasts  in the   process  of photo respiration.

 The number of peroxisomes per cell varies from 70 to100.  How and where  these are formed in the cells is not yet clearly understood. Possibly , these form  as buds from  cytoplasmic  reticulum  but  their  enzyme  are synthesized  by ribosomes   found free in the cytosol peroxisomes have  brief  life  span of 5 to6 days .Hence,  old ones are regularly  dissolved by autophagy and  new  ones are formed.

Glyoxysomes : are organelles similar  to peroxisomes   but contain enzyme  of  glyoxylate cycle  which  is concerned  with conversion  of fats to sugars. These occur in cells of fungi,  some protista  and germinating seeds. 


Related Discussions:- Peroxisomes and glyoxysomes

Productive use values, Productive use values This is the value of natu...

Productive use values This is the value of natural products harvested through commercial logging, agriculture or fisheries and medicines that generated products that are of co

Explain dextrins, Dextrins Dextrins are also polymers of D-glucose held...

Dextrins Dextrins are also polymers of D-glucose held by a(l,4) glycosidic linkages. Dextrins are,  in  fact,  formed due to partial hydrolysis of starch by  enzymes such as sa

What are lichens, What are lichens? How do fungi participate in this ecolog...

What are lichens? How do fungi participate in this ecological interaction? Lichens are produced by mutualist ecological interaction among fungi and algae or among fungi and cya

What do you understand by chromosome behaviour, Q. What do you understand b...

Q. What do you understand by Chromosome Behaviour? When we study meiosis. we not only observe the regularity of pairing which is important' for' the fertility of the plants, we

Blood clotting, BLOO D CLOTTING - It is a nature's device to check ...

BLOO D CLOTTING - It is a nature's device to check the excessive loss of blood from an injury. Bleeding time is 1-3 minutes. Clotting time is 2-6 minutes. Process of

Mirco, what is wrong with pasteurs conclusion

what is wrong with pasteurs conclusion

Show clinical symptoms of galactosemia, Q. Show Clinical symptoms of galact...

Q. Show Clinical symptoms of galactosemia? Clinical symptoms of galactosemia deficiency is found to appear early in infancy. Some infants are born with cataract, jaundice and

Explain changes in gastrointestinal tract of infants, Explain changes in ga...

Explain changes in gastrointestinal tract of infants? A full term baby has the ability to digest simple proteins, carbohydrates and emulsified fats. In first 3-4 months, the p

Formation of pronuclei , Formation of pronuclei : Information of pron...

Formation of pronuclei : Information of pronuclei, micronucles which is one of the conjugants, plays an important role. Micronucleus undergoes meiosis and forms four haplo

Explain turnover number, Explain Turnover number Turnover number:- Th...

Explain Turnover number Turnover number:- The  number  of  molecules  of substrate  transformed per catalytic  site of the enzyme per minute,

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