The Cell in its Environment

The Cell Membrane stars in:

What we ALREADY know:

•Cell membrane is found around the outside of an animal cell and it is the second layer of a plant cell

•The job of a cell membrane is to let “things” in and out of the cell

What we will soon KNOW:

•The Cell Membrane welcomes needed materials in 3 different ways…

•The Cell Membrane disposes of unneeded materials inside the cell by sending them out in 3 different ways…

Selectively Permeable:

= some materials can pass through an object while others cannot

Permeable= “to pass though” in Latin

1. Usually permeable to oxygen, water and carbon dioxide

2. Unlikely permeable to large objects and salts

3 Methods of Moving in and out of the Cell:

1. DIFFUSION2. OSMOSIS

3. ACTIVE TRANSPORT

Passive transport

A. PASSIVE TRANSPORT:

= the movement of materials across the membrane WITHOUT Energy

Let’s learn about the methods of PASSIVE transport……..

What will happen?!?

1. Diffusion:Process where molecules in high conc. will move to areas of low conc.

QUIZ!!!

2. Osmosis: Diff. of H2O

Neato fact: osmosis is what makes fresh and salt water fish so different…

B. ACTIVE TRANSPORT!!!

= the movement of materials through a membrane USING energy

1. Gross… it did what?!?!

Endocytosis!!! = 1) the cell membrane surrounds or engulfs a particle and then 2) it will pinch off to form a

vacuole around it in the cell (this still uses E)