1. Homework #1 is posted and due 9/17
Bonus #1 is posted and due 10/24
Discussions started this week

2. Expressing genes under the appropriate conditions is critical for development and survival.
Protein

3. Cells and organisms must monitor and respond to the environment.
Is there
anybody
out there?

4. What is the most critical internal and external stimuli for a human cell to perceive and respond to?

5. Signal transduction step by step: Perception

6. Signal transduction step by step: Transduction

7. Signal transduction step by step: Response
– such as changes in cellular components or production of new cellular components

8. Transduction can involve activation or inactivation of proteins.

9. Cellular responses may involve changes in the expression of genes.

10. Blood sugar levels as an example of cellular responses to the environment

11. Why so many steps?

12. Multiple steps allow for signal specificity.
Different relay molecules lead to different responses

13. Multiple steps allow for signal amplification:
Calcium is a simple method of amplifying signals