Download Active Cellular Transport Lesson 7 Biology 10 Movement of ions and

Active Cellular Transport
Lesson 7
Biology 10
Objective: You will be able to
-describe how large particles enter the cell
-define and differentiate between
endocytosis, exocytosis, facilitated diffusion .
Movement of ions and some large particles.
Recall that ions and insoluble particles cannot go
through the membrane. One method to get these
particles into or out of the cell is FACILITATED
DIFFUSION.
This does NOT require energy!
It is diffusion through a channel protein.
Note: a carrier molucule may be required to cross
the channel.
Movement of Very Large Particles Across
the Cell Membrane.
Very large particles cannot go through the cell
membrane (recall the scale of the video on the cell
membrane). They must be brought into or out of
the cell in special ways that require energy.
ACTIVE TRANSPORT
-movement of a substance from an area of LOW
concentration to an area of HIGH concentration (I.e.,
against concentration gradient)
-requires energy input and transport proteins in the
cell membrane
-most of the energy comes from cellular respiration
mitochondria turns glucose into a usable form of energy
(ATP)
Exocytosis
“outside cell”
vacuole forms around molecule
molecule can either be waste or something
manufactured in the cell that needs to be deliver
outside itself (e.g, hormone)
vacuole fuses to cell membrane and then opens on
outside to release contents into extracellular fluid
(ECF)
Endocytosis
(“inside cell”)
cell membrane wraps around large molecule and
encloses it
membrane pinches off and forms vesicle
two possible events follow:
vacuole joins with a lysosome and breaks down molecules
(used when cell brains in food)
vacuole moves to part of cell where molecule is needed and
empties content
Characteristics
Diffusion
Facilitated
Diffusion
Active Transport
Membrane
proteins
Yes/no
Yes
Yes
External energy
No
No
Yes
Movement
Down
Down
Against
Size of matter
Small
Larger
All sizes
Examples
H20, 02, H20
Glucose, calcium
ions
Amino acids, medicines
Occurrence
Dialysis,
oxygenation of Movement of glucose
in/out of cells
blood
Sodium - potassium pump in
neuron
Assignment
read pages 277 to 281
Do p. 283 # 1 to 9