1. The Scientific Method  What parts of the reflex experiment make up the scientific method?

2. Scientific Method  Ask a Question  Make a Hypothesis  Test the Hypothesis--Experiment  Analyze Results  Make a Conclusion

3. Variables  Dependent Variable What is effected by the independent variable.  Independent Variable What you control in the experiment

4. Variables  What were our independent and dependant variables in the Reflex Lab?

5. Variables  Control The experimental condition that receives no treatment. Ex. Drug testing Was there a control in the Reflex Lab?

6. Variables  Constants An experimental condition that does not change. Were there any constants in our reflex experiment?

7. Variables  Repeated Trials Why do we do this?  Experimental Error Were there any errors in the Reflex Lab?

9. The Central Nervous System  The Parts Brain ○ Collection of over 100 billion neurons collectively known as “grey matter” Spinal Cord ○ Contains 31 pairs of spinal nerves that connect the brain to the different parts of the body. Head, neck, shoulders, arms, hands, chest, abdomen etc.

10. Peripheral Nervous System  All the nerve cells outside the brain and spinal cord.  Two parts of Peripheral Nervous System Somatic NS = Voluntary Movement (Biking) Autonomic NS= Automatic Responses (blink etc.)

11. Question  Which part of the Peripheral Nervous System did we experiment on? How do you know?

12. What are Neurons? Neurons are special cells that help the different parts of the body communicate with the Central Nervous System, and Peripheral Nervous System.

13. Types of Neurons  Sensory Neuron (Input) A neuron that transmits towards the spinal cord and brain (messenger).  Motor Neuron (Output) A neuron that transmits away from the spinal cord and brain to the body (e.g. muscle control).

15. The Neuron

16. Neuron Function  Nerves from the Peripheral NS work together to let different parts of the body communicate messages to the brain and spinal cord.  The brain or spinal cord then sends a message back which results in a response known as…

17. REFLEXES!  A quick automatic response to a stimulus Voluntary and Involuntary!  Voluntary Reflex = the reflex game and lab These are more commonly known as RESPONSES  Involuntary Reflex Blinking Sneezing/Coughing Frightened jump (fight/flight response)

18. The Reflex Arc  The nerve pathway (loop) that activates a reflex. Part I: A stimulus activates a nerve that sends a signal to the spinal cord Part II: The spinal cord replies with a new message that results in a physical reaction (reflex!).

19. A Short Video  http://www.sumanasinc.com/webcontent /animations/content/reflexarcs.html http://www.sumanasinc.com/webcontent /animations/content/reflexarcs.html

20. The Response Arc (Voluntary)

21. The Reflex Arc (Involuntary)

22. What now?  Using your notes on experimental design, create an experiment that tests your INVOLUNTARY reflexes.