The document explains two processes by which cells move materials across their membranes: endocytosis and exocytosis. Endocytosis involves three types—receptor mediated endocytosis, phagocytosis, and pinocytosis—where cells either ingest large particles or dissolved substances. Phagocytosis, discovered by Ilya Metchnikoff, involves the engulfing of solid particles, while pinocytosis focuses on the intake of liquid or dissolved nutrients.

1. ENDOCYTOSIS
Mona khimsuriya

2. INTRODUCTION
• In diffusion , dissolved particles (solutes) move down
a concentration gradient.
• Sometimes cells need to move non- dissolved
particles, or large amount of material across the cell
membrane.
• They can do this by two processes : endocytosis and
exocytosis.

3. WHAT IS ENDOCYTOSIS AND
EXOCYTOSIS
• Endocytosis : endo (within) cytosis (cell)
• The process by which a cell moves large amounts of
material, or non- dissolved particles, into its
cytoplasm from the outside environment.
• Exocytosis : exo ( exit ) cytosis ( cell)
• The process by which large amounts of material or
large non –dissolved particles are moved from the
cell’s cytoplasm to the outside environment.

5. • The three types of endocytosis are :
1. Receptor mediated endocytosis
2. Phagocytosis
3. Pinocytosis

6. RECEPTOR MEDIATED ENDOCYTOSIS

7. • Receptor mediated endocytosis (RME) is the type of
endocytosis.
• RME is an endocytotic mechanism in which specific
molecules are ingested into cell.

8. DIAGRAMMATICALY EXPLANATION

9. STEPS OF RECEPTOR MEDIATED
ENDOCYTOSIS
• Step 1

10. • Step 2

11. • Step 3

12. • Step 4

13. • Step 5

14. • Step 6

15. • Step 7

16. • Step 8

17. • Last step

18. PHAGOCYTOSIS

19. • Phagocytosis is one type of endocytosis that occurs
when a cell uses its membrane to bring non-
dissolved particles solid particles into its cytoplasm.
• In phagocytosis,the cell extends finger – like
projections of its cell membrane called psedopods
around a piece of solid material outside of the cell.

20. WHO DISCOVERED PHAGOCYTOSIS ?
• Ellie Ilya metchnikoff discovered it in 1882.
• Received nobel prize for the Same in 1906.
• Carl fredrich claus coined the term phagocytosis.

21. • WBC remove bacteria and cell debris.
• Amoeba engulfs food
EXAMPLES

22. WHAT ARE THE CELLS INVOLVED IN
PHAGOCYTOSIS?
• Professional phagocytes
1. Neutrophils
2. Monocytes
3. Macrophages
4. Dendritic cells
5. Mast cells
6. Eosinophils

23. • Non professionals
1. Lymphocytes
2. Nk and LGL cells ( large granular lymphocytes)
3. Epithelial cells
4. Endothelial cells
5. fibroblast

24. HOW DOES IT WORK ?
1. Entry of the pathogen
2. Recognition & phagocytosis by tissue phagocyte
3. sos signals
4. Recruitment of phagocytes & inflammation.

26. PINOCYTOSIS

27. • Pinocytosis is another form of endocytosis in which
small particles are brought into the cell forming an
invagination and then suspended with in small
vesicles and then it breaks down the particles.
phagocytosis is also known as “ cell drinking”.
• Pinocytosis works just like phagocytosis but the only
difference other hand , pinocytosis is when the cell
engulfs already dissolved or broken – down food.

29. • Example
• Human egg cell taking up nutrients from
surrounding cells.

30. Thank you