explain the types and the formation of vesicles.for downloading the presentation ,more presentations , infographics and blogs visit : https://studyscienceblog.wordpress.com

1. Exocytosis and endocytosis

2. Exocytosis
• Types;
• 1) Ca2+ triggered non-
constitutive (i.e., regulated
exocytosis)
2) non-Ca2+ triggered
constitutive.
3) Vesicular exocytosis in
prokaryote gram negative
microbes is the latest finding in
exocytosis.

3. Non-constitutive or regulated exocytosis
• Each specialized secretory
cell produces large quantities
of a particular prod-uct—such
as a hormone, mucus, or
digestive enzymes—which is
stored in secretory vesicles for
later release.

4. Vesicle Budding Is Driven by the Assembly of a
Protein Coat

5. Vesicle Docking Depends on Tethers and
SNAREs

6. Endocytosis
• Types
• Pinocytosis (“cellular drinking”)
• Phagocytosis (“cellular eating”)
• Receptor-mediated Endocytosis

7. Specialized Phagocytic Cells
• Function;
• nutrition
• defend us against infection by
ingesting invading microor-
ganisms.
• ingulf dead and dam-aged
cells and cell debris.

8. Fluid and Macromolecules Are Taken Up by
Pinocytosis
• macrophage, for example,
swallows 25% of its own
volume of fluid each hour. This
means that it removes 3% of
its plasma membrane each
minute

9. Receptor-mediated Endocytosis
• receptor-mediated
endocytosis, provides a
selective concentrating
mechanism that increases the
efficiency of internalization of
particular macromolecules
• such as; Cholesterol-
containing LDLs, Vitamin B12
and iron

10. Endocytosed Macromolecules Are Sorted in
Endosomes
• Early endosome
–pH 6.5-6
• Late endosome
–pH 5.5-5
Lysosome
–pH 5-4.5
• transcytosis

11. Lysosomes Are the Principal Sites of
Intracellular Digestion
• They contain about 40 types
of hydrolytic enzymes
• ATP-driven H+ (proton) pump
• autophagy

12. Thanks for listening