1. The Paramecium is an organism that lives in fresh water
The Paramecium is an organism that lives in fresh water. Water is constantly diffusing into the Paramecium, and so the water is constantly forced back out.
This pushing of water from an area of lower to an area of higher concentration is know as
(1) ATP wasting (3) Passive transport
(2) Active transport (4) Respiration

2. Cellular communication
Or…talking membranes…

3. YEUCHHH!!!!

4. What is a smell?
Molecules move through air (or liquid).

5. What is a smell?
Molecules move through air (or liquid).
All molecules have shapes.

6. What is a smell?
Molecules move through air (or liquid).
All molecules have shapes.
The nose has RECEPTORS with matching shapes.

7. What is a smell?
Molecules move through air (or liquid).
All molecules have shapes.
The nose has RECEPTORS with matching shapes.
If the molecule reaches the receptor, the smell is communicated!

8. The message is intended for a TARGET cell.
The TARGET cell has receptors with the matching shape.
Other cell receptors MAY NOT BE targets.

9. Molecules A and B most likely represent (1) a protein and a chromosome
The diagram below represents two molecules that can interact with each other to cause a biochemical process to occur in a cell.
Molecules A and B most likely represent
(1) a protein and a chromosome
(2) a receptor and a hormone
(3) a carbohydrate and an amino acid
(4) an antibody and a hormone

10. Where are these receptors located?
Cell membrane
Where are these receptors located?
ON THE CELL MEMBRANE!

11. Cell membrane
The message does not enter the cell, it only gives the cell a signal to do something.

12. messenger
receptor
cell membrane
MESSAGE
RECEIVED!

13. The diagram shows the surface of a cell membrane.
What may be correct labels for A & B?
1) A = glucose, B = ATP
2) A = chemical message, B = receptor
3) A = cell wall, B = salt
4) A = antigen , B = neurotransmitter