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

The z-gene codes for permease, Select the two correct statements out of the...

Select the two correct statements out of the four (a - d) given below about lac operon. 1. Glucose or galactose may bind with the repressor and inactivate it 2. In the absenc

Coordination and response, Name the two hormones produced by the pancreas a...

Name the two hormones produced by the pancreas ans say in what circumstances, in what way, they adjust the glucose concentration in the blood.

System that permits movement and fixation to echinoderms, What is the syste...

What is the system that permits movement and fixation to echinoderms? The system that allows movement and fixation to substrates in echinoderms is known as the ambulacral syste

Physical properties of protoplasm, What is the physical experiment that sho...

What is the physical experiment that show that the protoplasm has contractility?

Explain the effect of deficiency of pyridoxine, Explain the effect of Defic...

Explain the effect of Deficiency of pyridoxine? A deficiency of vitamin B6 alone is uncommon because it usually occurs in association with a deficit in other B-complex vitamin

Leucosolenia, special character of leucosolenia

special character of leucosolenia

Explain the parathyroid gland cells, A new drug named AGON-CaSR has been de...

A new drug named AGON-CaSR has been developed that is an agonist at calcium-binding sites of CaSRs (Calcium-Sensing Receptors) in plasma membranes of parathyroid gland cells.

What do all organic compounds contain, What do all organic compounds contai...

What do all organic compounds contain? The key element is carbon. Organic compounds are all carbon-having compounds. By definition, an organic compound having carbon. Alt

Primary producers - biotic components , Primary producers - Biotic Componen...

Primary producers - Biotic Components The major primary producers of aquatic ecosystems (freshwater and marine) are various species of algae. In terrestrial ecosystems the ma

Ecology, does jellyfish depend on solarenergy

does jellyfish depend on solarenergy

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