Endocytosis Flashcards

Flashcards about Endocytosis

What is Endocytosis?

Cellular uptake of substances from outside, requiring energy.

What are the 2 main types of large-scale endocytosis?

Phagocytosis (cell eating) & Macropinocytosis (cell drinking).

What are the types of micropinocytosis (small vesicle uptake)?

Clathrin-mediated, Caveolin-mediated, & Constitutive micropinocytosis.

What is the main purpose of endocytosis?

To get nutrients into cells.

What are the "professional phagocytes"?

Macrophages, Dendritic cells, & Neutrophils.

What is the role of macrophage endocytosis?

To ingest and break down pathogens and dead cells.

What starts particle internalization in phagocytosis?

Receptor-ligand interaction on cell surface.

What cytoskeletal change happens during phagocytosis?

Actin polymerization.

What is a phagosome?

A vesicle formed after engulfing a particle during phagocytosis.

What does a phagosome fuse with?

An acidic lysosome.

What is phagocytosis mainly used for in complex organisms?

Defense.

What is Macropinocytosis?

Cell membrane ruffles inward in an actin-dependent manner.

What's inside a macropinocytosis vesicle?

Extracellular fluids and molecules.

What is Clathrin-mediated endocytosis for?

To uptake specific macromolecules.

What can mammalian cells ingest via Clathrin-mediated endocytosis?

Hormones, enzymes, cholesterol, iron, etc. (cell-type dependent).

What is Caveolin-mediated endocytosis?

Small flask-shaped invaginations with caveolin.

What is Caveolin-mediated endocytosis thought to do?

Cholesterol uptake.

What does Clathrin/Caveolin-independent endocytosis include?

Processes using flotillin, Cdc42, or Arf6.

What is the purpose of the bacterial endocytosis experiment?

Assess macrophage uptake of bacteria & Latrunculin A's effect.

Why run a control in the experiment?

To have a baseline for comparison.

What is a permeabilizing solution for?

To create pores allowing entry of labeling substances.

Why are bacteria visible under the microscope?

They are labeled with a green fluorophore.

Why count the number of bacteria in 5 macrophages?

To increase statistical reliability and accuracy.