Passive and Active TransportUnit 2- Cell Structure and Function

Outcomes:• Identify the factors

which influence the rate and direction of diffusion.

• Identify how osmosis is related to diffusion and the value of osmosis to living organisms.

• Examine the mechanisms of active transport by identifying and explaining the two processes.

• Compare the similarities and differences between active and passive transport.

**Don’t have to write these out**

Cellular Transport Cellular transport moves substances

_________the cell and moves substances ________and ________of the cell

There are 2 types:1. _________ Transport2. _________ Transport

Passive Transport These types of transport do not require

energy a) Diffusionb) Facilitated Diffusionc) Osmosis

A) Diffusion Remember from years before that

particles in solids, liquids, and gasses are in constant ___________ ___________(Particle Theory of Matter)

Substances dissolved in water move constantly in random motion

The random _________ of these _________ creates DIFFUSION

The amount of a substance in a certain area is called ___________________

Substances diffuse from an area of _________ concentration to an area of _________ concentration

Watch the following video and draw the diagram on the next page: http://

www.youtube.com/watch?v=Um6OoN81rb4

Diagram of Diffusion

Diffusion occurs until there is an __________ _______________ of particles in an area/cell

The particles continue to move randomly, but there is _____ ____________ ___________ this is called DYNAMIC EQUILIBRIUM

Rate of Diffusion 3 main factors affect the rate that

diffusion occurs1. _______________

When concentration is high, diffusion happens quickly because there are more particles to collide with each other

2. _______________ When temperature increases, the particles

collide more quickly3. _______________

When pressure increases, the particles collide more quickly

B) Facilitated Diffusion While water can diffuse readily across a

plasma membrane, most other substances need help

Happens through ____________ and _____________ proteins

The CHANNEL PROTEINS in the plasma membrane of the cell are used to diffuse ions and small molecules across the cell membrane (draw the diagram below)

http://kentsimmons.uwinnipeg.ca/cm1504/Image132.gif

CARRIER PROTEINS are also used to move substances across a cell membrane by ___________ _________ to help diffusion in a cell (Draw the diagram)

http://www.biologycorner.com/resources/simpdiff.jpg

C) Osmosis The _________ of water __________ a

selectively permeable ____________ is OSMOSIS

_____________ the movement of water across the plasma membrane is an important factor in maintaining homeostasis

(draw the next diagram)

http://www.biologycorner.com/resources/osmosis.jpg

If the __________________ of solute is higher on one side of the cell membrane, the water will move _____________ the __________ solute __________________

This diffusion happens until dynamic equilibrium occurs

Isotonic Solution When a cell is in a solution that has the

same concentration of water and solutes is said to be in an ISOTONIC solution

Water moves into and out of the cell at the same rate and cells keep their ______________ ___________

Hypotonic Solution If a cell is in a solution that has a lower

concentration of solute, the cell is said to be in a __________________ solution

There is more water outside of the cell than inside the cell which causes __________ to move __________ ____ ______

The water moving into the cell creates ___________ ___________

In an ________ cell, the water may enter the cell so much so that it ___________

A plant cell will ________ burst if there is a high osmotic pressure ____________ the cell __________ is very _________

Hypertonic Solution When the ________________ of the solute

____________ of the cell is _______than inside

________ __________ _________ the cell ___________ cells may __________ because

of water loss _______ cells ________because the water

vacuole is empty

Draw the diagram:

http://4.bp.blogspot.com/-yiAZAMJRq4s/Ta79K3vVk8I/AAAAAAAAACE/MhfD0z_ABi8/s1600/hypo.jpg

Video Explanation http://

www.youtube.com/watch?v=AYNwynwaALo

Active Transport This happens when substances have to move

from an area of __________ concentration to an area of __________ concentration

This process makes sure that cells have the proper ___________ of substances inside of them

These forms of cellular transport REQUIRE the use of ______________ by the cell

a) Pumps (carrier proteins)b) Endocytosis/Exocytosis

A) Pumps (Carrier Proteins) __________ proteins can move

substances against a concentration gradient

Some pumps move one type of substance in one direction across the plasma membrane

Other pumps move two substances in both directions across the plasma membrane

Sodium Potassium Pump This is a common type of pump moves 3 ___________ ions ______ of the cell moves 2 ___________ ions ______ the cell ATP (a form of energy) _______ _______ into

ADP to do this Video demonstration

http://www.youtube.com/watch?v=Q73uJ8WlY_E

http://4.bp.blogspot.com/_207DNIaL-gc/TOaSu8u3q7I/AAAAAAAAAV4/9QLnFO82wQA/s1600/07_16SodiumPotassiumPump.jpg

B) Endocytosis & Exocytosis Particles that are too large to travel

through the plasma membrane leave or enter the cell differently

Endocytosis when a cell ______________ something

_____________ of the cell The cell membrane __________ ________

and takes the substance inside the cell The substance is now in a __________ to

travel throughout the cell

Exocytosis Is when substances ___________ the cell

by vesicles ____________ the plasma _______________ to expel (get rid of) the substance

http://www.kscience.co.uk/as/module1/pictures/endoexo.jpg