Polymorphism in lysosomes, Biology

Assignment Help:

Polymorphism in Lysosomes

Polymorphism, i.e. existence of a structure in more than one form, is an important feature of lysosomes. Several different forms of lysosomes have been identified within the cell as primary lysosomes, secondary lysosomes, residual bodies and autophagic vacuoles

Primary lysosomes: These are newly formed organelles. They are believed to be derived from the maturing face of Golgi complex whose digestive enzymes have not yet taken part in hydrolysis.

Secondary lysosomes: are formed from fusion of primary lysosomes with the vesicles containing variety of substrates known as 'phagosome'. After fusion, their membrane undergoes a change and enzymes are activated so that the substrate is digested. After activation they may continue hydl-oiysis repeatedly. The secondary lysosomes which fuse. with vesicles containing extracellular substrite brought into the cell by endocytosis are known as heterophagic lysosomes or heterophagosome whereas lysosomes fusing with vesicles containing particles isola~cdf rom cell's own cytoplasm like mitochondria, microbodies, and fragments of endoplasmic reticulum are known as autophagic vacuoles. During pathological conditions or during cell growth, autodigestion of cellular organelles is a normal event.

Residual bodies:
lncomplete digestion of foreign substances leads to the formation of residual bodies. Residual bodies are huge, irregular in shape and are electron dense. In some cells they remain for a long time and play a role in the aging process. In some other cells, the content of the residual bodies leave the cell by exocytosis.

Lysosomes are responsible for the .intracellular digestion of a variety of substances such as food molecules, disease causing organisms, etc. This process is called heterophagy. Lysosomes are also responsible for digestion of cell's own cytoplasmic constituents. This process is called autophagy. It is important that lysosomes do not rupture and release their contents inside living cells as they would start digesting the cell and cell will die.


Related Discussions:- Polymorphism in lysosomes

Protein requirement during congestive cardiac failure, Q. Protein Requireme...

Q. Protein Requirement during congestive cardiac failure? Protein: The protein requirements remain the &me as healthy adult men and women, About 0.8 - lg of protein per kg

Inferior alveolar nerve, Inferior alveolar nerve Inferior alveolar ner...

Inferior alveolar nerve Inferior alveolar nerve repositioning to facilitate the placement of endosseous implants posterior to mental foramen is associated with very high incid

Which cannot react with dehydration reaction, Which of the following pairs ...

Which of the following pairs of functional groups CANNOT react with each other by a dehydration reaction? Select one: a. Carboxyl;Hydroxyl b. Carboxyl;Sulfhydryl c. Pho

Impoundments - lentic ecosystems, Impoundments - Lentic Ecosystems We...

Impoundments - Lentic Ecosystems We have so far discussed natural lakes. In addition to these there are a number of lakes both small and large artificially created by man cal

Procedure for quantitative determination of viable microbes, Explain for Pr...

Explain for Procedure Quantitative Determination of Viable Microbes? Now carry out the exercise following the steps included herewith: 1. Label the diluent tubes from 10 -1

Give a detailed account on central nervous system of frog, Question 1 Iden...

Question 1 Identify the specimen, class to which it belongs and write the salient features of that class.                                               Question 2 Write

Types of aortic stenosis-aortic stenosis-valve disease, Types of Aortic Ste...

Types of Aortic Stenosis:  Obstruction to left ventricular outflow is commonly at the valvar level. Less commonly it is at the sub valvar or supra valvar level. Sub valvar ob

What is cytogenetics, What is Cytogenetics? Before the advent of modern...

What is Cytogenetics? Before the advent of modern technology, the American biologists Thomas Hunt Morgan, G.W. Beadle, H. Sturtevant, Barbara McClintock, and others contributed

The signals for parturition originate from, The signals for parturition ori...

The signals for parturition originate from: 1. placenta only 2. placenta as well as fully developed foetus 3. oxytocin released from maternal pituitary 4. fully develop

What are dimorphic fungi, Question 1 What are dimorphic fungi? List the cl...

Question 1 What are dimorphic fungi? List the clinical manifestations produced by various dimorphic fungi. Add a note on isolation and identification of various dimorphic fungi

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