Feb. 10 – Diffusion and Osmosis

First of all, some review...

What do you remember about organelles?

Which organelle converts glucose into energy?

A)   Nucleus

B)   Ribosome

C)   Mitochondria 

D)   Vacuole

Which organelle transports materials?

A)   Endoplasmic reticulum

B)   Golgi body

C)   Cytoplasm

D)   Vacuole

What does a plant cell have that animal cells don’t have?

A)   Vacuole

B)   Nucleus

C)   Mitochondria

D)   Cell wall

What do ribosome do?

A)   Package materials

B)   Photosynthesis to create glucose

C)   Creates proteins

D)   Controls the cell

Then we started on the new topic

Learning Goals: Understand how diffusion and osmosis moves materials within cells.

Success Criteria: You can describe diffusion and osmosis using proper terminology.

Here are the notes I gave in class.

Diffusion

Concentration: how many particles are in one area.

High concentration: a lot of particles in one spot.

Low concentration: a few particles in one spot.

Diffusion is when particles move from high

concentration to lower concentration areas.

This is how nutrients move inside your cells.

Osmosis

Movement of water across a membrane.

Solution: Water with particles dissolved in it.

Solute: the particles in the water. (example: salt)

Osmosis: When water moves across a membrane towards the side with more solutes.

Then we did an demonstration using carrots.

-----------------------------------------------------

Osmosis demonstration

                       Day 1                   Day 2           Day3

Carrot A:       7.23 g

Carrot B:       7.41 g

(salt)

Hypothesis:

Carrot B should get lighter (hypertonic).

Carrot A should get heavier (hypotonic).

-----------------------------------------------------

Hypertonic: More solutes outside the cell.  The cell shrinks.

Hypotonic: Less solutes outside the cell.  The cell grows.

Homework

Complete this handout: Diffusion and Cell importance