1. Nervous System

2. Arrange in the correct order
Levels of Organization
Arrange in the correct order

4. How are humans organized?
Cells (~300 types)
Tissues (4 tissue types)
Organs
Organ System (12 organ systems)
Organism

5. How are Humans Organized
Cells-specialized cells perform specific function
Tissues- groups of similar cells that perform single function (muscle cells all do the same thing)
Organs- group of similar tissues that perform a complex function (sight)
Organ system -groups of organs performing closely related functions
Organism

6. Homeostasis
Homeostasis- The process by which organisms keep constant/near constant internal conditions despite changes in the external environment
The nervous and endocrine systems are in charge of maintaining homeostasis.

7. Nervous System Function
Body system made up of cells that control and coordinate the other body systems to maintain homeostasis and respond to internal and external conditions Simplified—It’s the body’s major communication system

8. Neurons
The cells that make up the nervous system are called neurons These cells carry information in the form of electric and chemical signals called nerve impulses Information is electric through the neuron and chemical between Resting potential- no electric signal Action potential- carrying an electric signal

10. 3 types of neurons
Internerons = interpret information. Nerve cells that make up your brain Decide
Explain to your shoulder partner what sensory neurons do and what a nerve impulse really is
sensory neurons = 5 senses
nerve cells that gather information and send it to the brain
motor neurons = movement
nerve cells that carry messages from the brain to the body for movement
Explain to your face partner what interneurons and motor neurons do
Nerve impulse-electrical message carried to/from the brain

11. 3 types of neurons sensory neurons = 5 senses
nerve cells that gather information and send it to the brain
2) Interneurons = interpret information.
nerve cells that make up your brain
3) motor neurons = movement
nerve cells that carry messages from the brain to the muscles/body for movement

12. A B
Impulse C

14. Activating the nervous system
Stimulus- anything that activates a sensory neuron Name the stimulus sensory neurons in eyes- sensory neurons in ears- sensory neurons in body- sensory neurons in nose- sensory neurons in mouth-

16. Muscle
Motor
Neuron
Interneuron
Skin receptors
Sensory
Brain

17. Neuron Parts Cell body- contains the nucleus; receives messages
Metabolic activity
Dendrites-
Receives from environment or another from cell body
Myelin sheath/nodes- covers axon
Axon- pathway for impulses
increases the speed which impulses can be sent.

18. Dendrite receives nerve impulse/signal
Dendrite receives nerve impules/signal
Dendrite receives nerve impules/signal
Dendrite receives nerve impules/signal

20. Neuron anatomy

22. Division of the Nervous System
Central Nervous System (CNS)- Brain and Spinal Cord.
Peripheral Nervous System (PNS)- nerves and associated cells that are not part of the brain or spinal cord.

23. Central or Peripheral Nervous System
Central – the processing center of the nervous system. Receives info from AND sends info to the peripheral nervous system. Makes decisions

24. Central or Peripheral
Peripheral- Has 2 Parts
Somatic Nervous System- regulates activities under conscious control
Wiggling toes, writing, talking, etc.
Reflex arc- pathway that an impulse travels.
Ex: Stepping on a tack
Sensory receptor (toe) to sensory neuron to motor neuron to effectors (leg muscle) to pull away from tack.
Autonomic nervous system- regulates involuntary/automatic activities.
Heart rate, breathing, etc.

26. The Synapse ?
Impulse B A

27. B A Axon Dendrite Terminal What do you think Write your answer
Neurotransmitters
Impulse
Impulse
Write your answer
On the right
What do you think
Neurotransmitters
Do? B A

28. Sending Impulses
The synapse is a gap where 2 neurons meet (but don’t touch).
Neurotransmitters are chemicals that carry the impulse OVER that gap.

29. Sending Impulses
1.) A neuron is stimulated by another neuron or the environment.
2.) Protein channels allow ions to move across to transmit the impulse
3.) Impulses only travel in one direction.

30. Which is Correct ?

33. Draw and label synapse/neurotransmitter

34. Sending Messages
Resting potential- Resting Potential is when a neuron is NOT receiving a signal.
Concentration of negative proteins and positive charge potassium ions(K+) is greater inside the cell than outside.
Also, concentration of sodium ions(Na+) is greater outside the cell then inside.

35. Sending Messages
Action potential- inside of a membrane temporarily becomes more positive than the outside (reversal of charges from negative to positive- how a message is sent).
Works like dominoes
An impulse (message) reaches the axon terminal then a neuron contacts another cell.
Synapse- location where a neuron can transfer a message.

37. Nerve impulse
Synapse
Neurotransmitter