bio ch 3.5 Active Transport, Endocytosis, and Exocytosis
Phagocytosis means
"cell eating"
cells use energy to transport materials that cannot diffuse across a membrane.
.
endocytosis and exocytosis transport materials across the membrane in vesicles.
.
two characteristics that almost all transport proteins share
1. all span the membrane 2. most change shape when they bind to a target molecule
what three things happen during both endocytosis and exocytosis?
1. they both make a pocket around their substances 2. both form a vesicle 3. both release their substance out of the vesicle in the end
Phagocytosis
A type of endocytosis in which a cell engulfs large particles or whole cells
most active transport proteins use energy from the breakdown of
ATP
active transport uses energy from
ATP molecules
during endocytosis, the vesicle fuses with what?
a lysosome
What process drives molecules across a membrane against a concentration gradient?
active transport
endocytosis, exocytosis, and phagocytosis are all examples of
active transport
How is active transport different from simple and facilitated diffusion?
active transport goes against a concentration gradient, whereas any type of diffusion goes down a concentration gradient
active transport can use transport proteins to move molecules
against concentration gradient (low to high)
exocytosis is the opposite of
endocytosis
which type of cytosis forms a vesicle, and then fuses with a lysosome or other type of vesicle?
endocytosis
Active transport requires
energy
which type of cytosis forms a vesicle that then fuses to the cell membrane and moves to the surface of the cell?
exocytosis
what would a substance be transported in a vesicle?
if the substance is too large to cross the membrane
against the concentration gradient means from
low to high
active transport goes from a region of
low to high concentration, against the flow of traffic, against concentration gradient
Going against the concentration gradient means going from
lower region of concentration to higher region of concentration
During endocytosis, the vesicle membrane fuses with a lysosome, and the membrane and its contents are broken down by ____________.
lysosomal enzymes
in an endocytosis event, what breaks down the vesicle membrane?
lysosomal enzymes
Phagocytosis is cell eating, and
makes a pocket around the material
in Endocytosis,
membrane wraps around smth and pulls in inside the cell(engulfing)
endocytosis is the
movement of liquids or large molecules into a cell by engulfing them in a membrane
cell membrane makes a "pocket" around what
phagocytosis
what is it called when a cell engulfs large particles or whole cells?
phagocytosis
what term means "cell eating?"
phagocytosis
transport proteins are called
pumps, and move materials against a concentration gradient
exocytosis
releases substances from a cell
exocytosis does what to substances
releases them out of the cell
exocytosis, exo means
releasing, letting a substance out of the cell
active transport
requires energy by cell to move certain materials in or out of the cell
in Exocytosis,
smth a cell wants to get rid of pushes up against the cell membrane and then pops out
endocytosis does what to substances
takes them into a cell
endocytosis, endo means
taking in, bring a substance into a cell
How is active transport similar to facilitated diffusion?
they both use transport proteins to move molecules through selective membranes
they key distinguishing feature of active transport proteins in that
they use chemical energy to move a substance against its concentration gradient
A cell may transport a substance in _____ if the substance is too large to cross the membrane
vesicles
Phagocytosis plays a key role in
your immune system, (white blood cells)
