Chapter 4

Exchange with the EnvironmentCell Energy

The Cell Cycle

Essential question on cells:

This chapter answers the

diffusion osmosis Active transport

endocytosis

exocytosis

Passivetransport

Fluency Chart

Section 1

Exchange with the Environment

Movement of “Tiny” particles:

Called Diffusion.

The movement of particles from high concentration to an area of low concentration. Happens in gases, liquids, and solids Ex. Of tiny particles: O2, H20, CO2

Gases diffuse in other gases…

Liquids diffuse into other liquids…

Solids diffuse into other solids…

Particles always move…

Brainpop

It’s about the membrane silly!

•The membrane is made of phospholipid molecules. They have two parts to them. One is the two hydrophobic tails. The other is the hydrophilic head.

Diagram of a membrane:

Plant and Animal Cell Rap

A special diffusion of H20 across a

cell membrane

Water moves from high concentration to low concentration

OSMOSIS:

Osmosis…

Diagram of how osmosis works:Extreme osmosis:

Tap the cell

A comparison……

diffusion osmosis

both

                                                 

   

Movement of “small ” particles:

Examples are sugars or amino acids These can’t pass through the

“phospholipid molecules” in the cell membrane

Need special protein channels to get in.

TWO types of movement:

1) Passive transport

Particle diffuses through protein channels from an area of high concentration to an area of low concentration

Does not require any energy

2) Active Transport

Movement of particles through proteins against the normal direction of diffusion.

(low to high concentration)

Requires the cell’s ATP (needs energy)

protein channel

Diagram of active transport:

Passive and Active Transport

Passive Active

Both

CELL MEMBRANE:

Tap the pic.

Moving Large Particles:

Two ways :

1) Bringing things in…Endocytosis 2) Getting things out of the cell…

Exocytosis video

Animation of exocytosis:

happens through

special type

depends on

happens w/o needing energy

requuires cell's ATP

depends on

moving big things in

moving big things out

Cell Exchange

Diffusion

Osmosis

particle Size-

small

passive transport

active transport

particle size- large

EndocytosisExocytosis

Concept map…