1. Bellringer Take out the following notes packets: Take out the following notes packets: Mollusks Mollusks Arthropods Arthropods Echinoderms Echinoderms Vertebrates/Fish Vertebrates/Fish Amphibians Amphibians

2. Introduction to Systems Lesson EQ: What are the levels of organization in the body?

3. Multicellular organisms are organized in to these levels: Multicellular organisms are organized in to these levels: Cells  tissues  organs  organ systems Cells  tissues  organs  organ systems Example: Example: Liver cell  liver tissue  liver  digestive system Liver cell  liver tissue  liver  digestive system All organ systems work to maintain homeostasis All organ systems work to maintain homeostasis Organisms want to keep their insides consistent, even though the environment changes Organisms want to keep their insides consistent, even though the environment changes Example: temperature, water level Example: temperature, water level

4. The Nervous System Lesson EQ: How does the nervous system carry out communication within the body? What are the three types of neuron?

5. Activator Brain drain: How does your body receive information? How does it make decisions about how to respond? How does it communicate in order to make responses?

6. Function: controls and coordinates functions throughout the body, responds to internal and external stimuli. Function: controls and coordinates functions throughout the body, responds to internal and external stimuli. Impulses- the messages carried by the nervous system, have the form of electrical signals Impulses- the messages carried by the nervous system, have the form of electrical signals Neurons- cells that transmit the impulses Neurons- cells that transmit the impulses

8. Usually the neuron is in a state called resting Usually the neuron is in a state called resting When it receives a message, it carries it to the next neuron in line. This is called action potential When it receives a message, it carries it to the next neuron in line. This is called action potential States of a Neuron

9.  this way  Message received Message sent

10. Link Link Link Summarizer: talk with your partner about how our activity represents the function of the nervous system Summarizer: talk with your partner about how our activity represents the function of the nervous system What did each student represent? What did each student represent? What were you “passing”? What were you “passing”?

11. Nervous system has two divisions: Nervous system has two divisions: Central Nervous System (CNS) Central Nervous System (CNS) Brain and spinal cord Brain and spinal cord Peripheral Nervous System (PNS) Peripheral Nervous System (PNS) Everything else Everything else

12. Sensory neurons- Carry impulses from sense organs to the CNS Sensory neurons- Carry impulses from sense organs to the CNS To the brain To the brain Interneurons- Connect sensory & motor neurons, carry impulses between them. Interneurons- Connect sensory & motor neurons, carry impulses between them. In the brain In the brain Motor neurons- Carry impulses from the CNS to muscles & glands Motor neurons- Carry impulses from the CNS to muscles & glands Away from the brain Away from the brain 3 Types of Neurons

13. Activator 1’s….explain how messages are transmitted through the body 2’s…..explain the pathway between the three types of neurons

14. Synapse- small gap between neuron and the next cell Synapse- small gap between neuron and the next cell Neuron transfers impulse to another cell Neuron transfers impulse to another cell Contains tiny sacs filled with neurotransmitters Contains tiny sacs filled with neurotransmitters The Synapse

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16. Neurotransmitters- chemicals used by a neuron to transmit an impulse across a synapse to another cell. Neurotransmitters- chemicals used by a neuron to transmit an impulse across a synapse to another cell. Within a neuron is an electrical signal, between neurons is chemical Within a neuron is an electrical signal, between neurons is chemical

17. Steps: Steps: 1. Action potential arrives at the end of the neuron. 1. Action potential arrives at the end of the neuron. 2. Causes the release neurotransmitters into the gap 2. Causes the release neurotransmitters into the gap 3. They diffuse across gap, attach themselves to receptors on the next cell 3. They diffuse across gap, attach themselves to receptors on the next cell Link Link Link Summarizer: talk with your partner about how our activity represents the passage of an action potential across the synapse Summarizer: talk with your partner about how our activity represents the passage of an action potential across the synapse What did the ball represent? What did the ball represent? What were you “passing”? What were you “passing”?

18. Vesicle Axon Axon terminal Synaptic cleft Neurotransmitter Receptor Dendrite of adjacent neuron Direction of Impulse Section 35-2 Figure 35-8 The Synapse

19. Summarizer Talk to your partner about what would happen if your body did not have neurotransmitters

20. Write an analogy about the nervous system, and share with your buddy Write an analogy about the nervous system, and share with your buddy Use this format: __________ is like ________ because ________________. Use this format: __________ is like ________ because ________________. Examples: Examples: “Neurons are like gossipy people because they pass information to one another. “Neurons are like gossipy people because they pass information to one another. “Homeostasis is like __________ because _________________.” “Homeostasis is like __________ because _________________.” Summarizer