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

Tolerance model - models of succession, Tolerance Model - Models of Success...

Tolerance Model - Models of Succession In this model, the presence of early successional species is not essential, that is, any species can start succession. Some species are

What are the three parts of a dna nucleotide, What are the three parts of a...

What are the three parts of a DNA nucleotide, and how are they connected to each other? The three types are a deoxyribose sugar, a phosphate group, and a nitrogenous base. The

What is atom, What is atom? Atoms are the smallest component of matter ...

What is atom? Atoms are the smallest component of matter that determine its unique chemical and physical properties. They are composed of negatively charged electrons, positive

Explain matching energy intake to energy expenditure, Explain Matching ener...

Explain Matching energy intake to energy expenditure? To be in energy balance, an athlete needs to consume about the same number of calories that he or she expends on a daily

Define historical development of food processing, Define Historical Develop...

Define Historical Development of Food Processing? Food processing began thousands of years ago to help people keep food through the lean seasons. Several methods of preserving

What is the salivary digestive enzyme, What is the salivary digestive enzym...

What is the salivary digestive enzyme? Which type of food does it digest and into which smaller molecules does it transform the food? The salivary hydrolase is called as saliva

Are mollusc metameric beings, Are mollusc metameric beings? Exclusively ana...

Are mollusc metameric beings? Exclusively analyzing this feature could it be said that molluscs are evolutionarily proximal to nematodes or to annelids? In molluscs there is no

Define counseling and compliance for celiac disease, Define Counseling and ...

Define Counseling and compliance for celiac disease? If symptoms do not improve, the child's diet should be reviewed and evaluated. A decrease in diarrhoea, increase in height

Explain the phases of swallowing process in dysphagia, Explain the Phases o...

Explain the Phases of swallowing process in Dysphagia? i) Oral Phase: In this, food is placed in the mouth, mixed with saliva, chewed if required and formed into a bolus by t

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