Transcript Cell Transport PPT - Effingham County Schools

Anatomy and Physiology
Cell Transport
Types of Transport
Diffusion
• Characteristics
– Particles move from
an area of high
concentration to an
area of low
concentration.
– Moves “down” or
“with” the
concentration
gradient.
– Does not require
energy.
Types of Transport
• Factors effecting the rate of
diffusion
– Temperature - as temperature
increases, rate of diffusion increases.
– Pressure - as pressure increases, rate
of diffusion increases.
– Steepness of the concentration
gradient - the steeper the gradient,
the faster the rate of diffusion.
Types of Transport
• Diffusion will continue until dynamic
equilibrium is reached.
• Dynamic equilibrium - continuous
movement of particles, but no overall
concentration change. (Everything is
equally distributed).
Type of Transport
Osmosis
• Characteristics
– Movement of
water across a cell
membrane.
– Cell has no control
over movement of
water. It continues
to move until
[inside] =
[outside].
[ ] =concentration
Osmosis - Types of Solutions
Isotonic
• [water inside] =
[water outside]
• Dynamic
equilibrium
reached
immediately.
Normal Red blood cells
Osmosis - Types of Solutions
Hypotonic
• [water inside] <
[water outside]
• Solutes are higher
inside the cell.
• Water flows in, cell
swells.
• Cell could burst if
water flow
continues.
Swollen red blood cells
Osmosis - Types of Solutions
Hypertonic
• [water inside] >
[water outside].
• Solutes are higher
outside the cell.
• Water leaves the
cell, cell shrinks.
Dehydrated red blood
cells
Types of transport
Passive vs. Active Transport
• Passive - no energy required
• Active - energy required
Types of Transport
• Passive Transport
– Movement across
a membrane by
diffusion.
– Facilitated diffusion
- moves down the
concentration
gradient with the aid
of a protein molecule.
• Most glucose
moves this way
Types of Transport
• Active Transport
– moves from an area
of low concentration
to an area of high
concentration.
– Moves up or against
the concentration
gradient.
– Glucose moving from
blood stream into
liver for storage.
Types of Transport
• Bulk Transport
– Moving large particles across the cell
membrane.
– Endocytosis - movement into the cell
– Exocytosis - movement out of the cell
Bulk Transport
• Endocytosis - 2 types
– Pinocytosis- bulk
transport of liquids
into the cell.
– Phagocytosis- “cell
eating”- bulk transport
of solids into the cell.