Types of transport include passive transport which does not require energy and active transport which uses protein pumps and channels to move substances across membranes. There are several types of active transport including bulk transport, endocytosis, and exocytosis. Endocytosis brings material into the cell through phagocytosis, pinocytosis, or receptor-mediated endocytosis while exocytosis expels material from the cell. Phagocytosis engulfs solid particles, pinocytosis brings in extracellular fluid through membrane invagination, and receptor-mediated endocytosis specifically uptakes substances bound to cell surface receptors. Both endocytosis and exocytosis use vesicle formation and membrane fusion but transport materials in opposite directions with endocytosis importing and exocytosis exporting.

1. Types of Transport
Passive
That does not use
Energy
Active
That uses Energy
Through a membrane Using a protein Protein pump
Using a protein
Bulk transport
No protein
Endocytosis
In to cell
Exocytosis
Out of the cell
Channel protein
Facilitated
diffusion
Simple diffusion
Osmosis Phagocytosis Pinocytosis
Receptor-mediated
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2. exocytosis and endocytosis:
transport larger molecules such as proteins and polysaccharides, and even
very large particles.
Exocytosis : a process in which material inside a cell is packaged into vesicles
and excreted into the extracellular medium.
Endocytosis : a process in which the plasma membrane invaginates or fold inward,
to form a vesicle that brings substances into the cell .
Definition :
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3. Exocytosis VS Endocytosis
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4. Endocytosis
•What Is Endocytosis?!What Is Endocytosis?!
•EEndocytosisndocytosis is a generalized term for whenever a cell takes in large molecules is a generalized term for whenever a cell takes in large molecules
and other particulate matter available outside the cell. It does so in three differentand other particulate matter available outside the cell. It does so in three different
ways: phagocytosis, pinocytosis, and receptor-mediated endocytosis.ways: phagocytosis, pinocytosis, and receptor-mediated endocytosis.
•Phagocytosis – solidPhagocytosis – solid
•Pinocytosis – liquid (general)Pinocytosis – liquid (general)
•Receptor-mediated
EndocytosisEndocytosis::
•Uptake of substancesUptake of substances
•Transport of protein or lipid components of compartmentsTransport of protein or lipid components of compartments 5

5. There are three main kinds of endocytosis:
• Phagocytosis: or cellular eating, occurs when the dissolved
materials enter the cell. The plasma membrane engulfs the solid
material, forming a phagocytic vesicle.
• Pinocytosis: or cellular drinking, occurs when the plasma
membrane folds inward to form a channel allowing dissolved
substances to enter the cell. When the channel is closed, the liquid is
encircled within a pinocytic vesicle.
•Receptor-mediated: chemical (LDL carrying cholesterol) binds to
receptor protein before being brought into the cell; specific
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6. Phagocytosis (phag·o·cy·to·sis )
Definition :
the ingestion of bacteria or other material by phagocytes and amoeboid
protozoans
Phagocytosis
STEPS
Step 1: Recognition Step 2: Engulfment
Step 3: Digestion Step 4; Expulsion
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7. • Recognition : Phagocytes have proteins called cell surface
receptors. these bind to the antigenic determinants of pathogens.
Recognizes cells different from self. LPS of gram negatives.
Peptidoglycan.
• Engulfment :Once attached, the macrophage extends pseudopods
around the pathogen and engulfs it, producing a phagosome.
• Digestion : Phagosome merges with a lysosome forming a
phagolycosome, and the chemicals within it diges the pathogen. 30 min
or less!
• Destructon : within the phagolysosome: Oxygen=dependent system,
oxidazing burst. Enzymes. Nitric oxide. undigested debris are release.
• Expulsion : after digestion the phagolysosome fuses with the cell
membrane and expels undigested materials.
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8. Phagocytic cells
Neutrophils
primary components of pus
Eosinophils
Monocytes transformed. scavengers
Macrophages
primary responders to parasitic infections.
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9. Pinocytosis (pin-o-cy-to-sis)
cell-drinking; EVERY CELL DOES THIS.
Definition :
• Pinocytosis is the movement of liquid through the membrane of a cell whereas
phagocytosis is the movement of solids.
In pinocytosis, or "cell drinking," the cell engulfs extracellular fluid, including
molecules such as sugars and proteins.
These materials enter the cell inside a vesicle, although they do not mix with
cytoplasm. Epithelial cells in capillaries use pinocytosis to engulf the liquid portion
of blood at the capillary surface.
The resulting vesicles travel across the capillary cells and release their contents to
surrounding tissues, while blood cells remain in the blood
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10. Steps of Pinocytosis :
1) Formation of little vesicles that takes sips of extracellular fluid
2) Membrane fold inward and small volumes of fluid are taken up.
3) Important for uptake of nutrients: cells in the digestive tract (particular intestine).
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11. Explain how phagocytosis and pinocytosis are similar and different.
Similar
Both involve the folding
Of the plasma membrane
Both are active transport
Both are forms of
Endocytosis
Both bring materials into
the cell
Different
Phagocytosis is
bringing in large
Particles/cells
Pinocytosis is bringing
In fluids and dissolved
substances.
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12. Receptor-
mediatedDefinition :
Receptor mediated endocytosis is a process by which cells internalize molecules or
viruses. As its name implies, it depends on the interaction of that molecule with a
specific binding protein in the cell membrane called a receptor .
Receptor-mediated endocytosis differs from the other two forms
of endocytosis in that it is very specific as to what it takes in. Think of it like someone
who is a very picky eater, like a child. They will only eat hotdogs and will refuse to eat
anything else, so you have to make them hotdogs.
How is it so specific?
Well, inside of the cell membrane there are specific proteins that are exposed to the
fluids outside of the cell, called the extracellular fluid. These proteins will only allow
certain substances to attach to them. Think of it as a cellular lock and key.
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13. Receptor-mediated steps :
•Step 1 (Binding) : receptors in clathrin-coated pits bind with specific materials.
•Step 2 (invagination) : invagination of the plasma membrane occurs forming a clathrin-
coated vesicle.
•Step 3 (uncoating) : the vesicle loses its clathrin coat and becomes an uncoated vesicle.
•Step 4 (fusion) : the vesicle fuses with an endosome.
•Step 5 (recycling) : the vesicle divides and recycles the receptors to the plasma membran
via transport vesicles.
•Step 6 (digestion) : another transport vesicle transports the ligands toward a lysosome;
enzymes in the lysosome digest the ligands.
The specific substances that attach to these receptor proteins actually have a specific
name, called “ligands “ . In Latin, 'ligare' means 'to bind,' so these substances are literall
binding substances. 14

14. 15
Receptors bind with ligands like key-
lock

15. Exocytosis
So What doesSo What does Exocytosis mean ?mean ?
Exocytosis is a process occurring in plant and animal cells that involves moving
materials within a cell to the exterior of the cell.
This process requires energy and is a type of active transport.
Exocytosis is the opposite of endocytosis in which substances are
taken into cells. In exocytosis, membrane-bound vesicles containing
cellular molecules are transported to the cell membrane.
Let's look at some examples of cellular secretory products :
•Secreted protein - enzymes, peptide hormones, and antibodies.
•Neurotransmitters from nerve cells.
•Plasma membrane proteins.
•Antigens - pieces of bacteria or other invaders which stimulate the immune
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16. Exocytosis is similar in function to endocytosis but working in the
opposite direction.
Exocytosis
stepsFive steps are involved in exocytosis:
Vesicle Trafficking:
In this first step, the vesicle containing the waste product or chemical
transmitter is transported through the cytoplasm towards the part of the cell
from which it will be eliminated.
Vesicle Tethering
As the vesicle approaches the cell membrane, it is secured and pulled towards
the part of the cell from which it will be eliminated.
Vesicle Docking
In this step, the vesicle comes in contact with the cell membrane, where it
begins to chemical and physically merge with the proteins in the cell 17

17. Vesicle Priming
In those cells where chemical transmitters are being released, this step involves
the chemical preparations for the last step of exocytosis.
Vesicle Fusion
In this last step, the proteins forming the walls of the vesicle merge with the cell
membrane and breach, pushing the vesicle contents (waste products or
chemical transmitters) out of the cell. This step is the primary mechanism for the
increase in size of the cell’s plasma membrane.
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18. What are the similarities and differences between endocytosis and
exocytosis?
Similarities
Both are involved in
transporting big molecules
across the membrane.
Both use a vesicle.
Both need energy.
Differences
Endocytosis brings materials to
the inside of
the cell while exo takes them out.
Exoocytosis has the vesicle being formed in
the golgi apparatus which then fuses with the membrane,
while endo has the vesicle. formed from
the cell membrane which then gets into the cytoplasm.
Exocytosis increases the size of
the cell membrane
while endo does the opposite.
•Now I'd like to finish with a summary of the main points.
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19. Well, I think I've covered everything.
I hope you enjoyed my
presentation
and if you have any question, feel
free to ask me now…. Thank You..