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

What are the main intraspecific ecological interactions, Q. What are the ma...

Q. What are the main intraspecific ecological interactions? The major harmonious intraspecific ecological interactions are societies and colonies. The major inharmonious intras

Name some standard activation energy, The standard free energy change and s...

The standard free energy change and standard activation energy for four biochemical reactions are listed in the table below: A few interpretations are given below. Between thes

What are the processes of the photochemical stage, What are the processes o...

What are the processes of the photochemical stage of the photosynthesis process? Photolysis of water, with liberation of molecular oxygen, and photophosphorylation of ADP, with

Explain pasteurization, Explain Pasteurization The act or process of h...

Explain Pasteurization The act or process of heating a beverage or other food, to a specific temperature for a specific period of time in order to kill microorganisms that cou

Heart in fishes, Fishe s - Heart is 2 chambered 1 auricle & 1 ventr...

Fishe s - Heart is 2 chambered 1 auricle & 1 ventricle present. Sinus venosus, truncus or conus arteriusus present. Only impure blood come in heart so heart is venous he

Structure of the teeth, Describe the structure of the teeth? How is this ti...

Describe the structure of the teeth? How is this tissue modified to carryout its function?

Heredity and variations, HEREDITY 1.         Like begets like i.e; ever...

HEREDITY 1.         Like begets like i.e; every living organism reproduces its own kind. Frog reproduce frogs, rats reproduce rats only. 2.         Heredity includes the cha

Give source organism of the dna polymerase used in pcr, a) Mention the numb...

a) Mention the number of primers needed in each cycle of polymerase chain Reaction (PCR) . Write the role of primers and DNA polymerase in PCR. b) Give the characteristic fea

Define supplementary feeding to control under nutrition, Define Supplementa...

Define Supplementary feeding to control under nutrition? Supplementary feeding has remained an important component to control under nutrition. Considering the dietary inadequac

Explain assessment of iron status - transferrin receptors, Explain assessme...

Explain assessment of iron status - Transferrin receptors? Transferrin receptors: As iron deficiency progresses into second stage, the number of transferrin receptors on the ce

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