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

Weaning the infant from the incubator, Weaning the Infant from the Incuba...

Weaning the Infant from the Incubator When heater output reading is minimal or nil it suggest that infant is capable of generating enough metabolic heat to keep himself war

Explain biochemical or physiological risk factors, Explain Biochemical or P...

Explain Biochemical or Physiological Risk Factors ? The biochemical or physiological risk factors are those abnormalities, some of which are metabolic in nature, which give ris

Explain the techniques of numerical taxonomy, Explain the Techniques of Num...

Explain the Techniques of Numerical Taxonomy Many other techniques of numerical taxonomy are available now, some with special objectives. Classification based on the methods

Primitive nervous system - nerve net, Primitive Nervous System - Nerve Net ...

Primitive Nervous System - Nerve Net A nervous system creates its appearance for the first time in the phylogeny among Cnidaria. In this group the nerve cells make an irregula

Species diversity indices, From an ecological point of view, species richne...

From an ecological point of view, species richness alone has limited value. More meaningful measures use the number of different species in a given area (species richness) as well

Anomalies related to oral cavity, Anomalies Related to Oral Cavity   Un...

Anomalies Related to Oral Cavity   Under these anomalies we will briefly discuss the cleft lip and cleft palate.  You must have seen and/or nursed a baby born with a cut on

Cell cycle, The cell cycle undergoes a sequence of changes which invol...

The cell cycle undergoes a sequence of changes which involve a period of growth replication of DNA, Followed by cell division. This sequence of changes is called cell cycle.

Tissue valves -surgical techniques, Tissue Valves :  Tissue valves mo...

Tissue Valves :  Tissue valves mounted on a frame with a sewing ring are inserted by the same technique as used in the case of prosthetic valves.

Camptotheca acuminata, This species is an ornamental tree in China, and has...

This species is an ornamental tree in China, and has yielded the clinically active agents topotecan, irinotecan, and 9 -aminocamptothecin, which are semisynthetically derived from

Mechanism of movements, Normal 0 false false false EN-I...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

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