1. Nervous System

2. Squid vs. Human

3. Nervous System of a Squid
The squid has the most complicated brain of all the invertebrates.
Has 300,000,000 neurons.
Squid and Octopi have "good" memories and can also learn.
The eyes are similar to mammals
They have a cornea, lens, iris and retina. It can also focus and form images.
It is different because instead of changing the shape of the lens it actually moves the lens closer and further away from the retina.
The squid has NO blind spot because the optic nerve leaves from the outside of the eyeball.

4. Anatomy of a squid

5. Neurons Nerve cells Made up of a cell body and branches
Axon – carries messages away from the cell body
Dendrites - receive messages

6. Types of neurons
Sensory neuron - receive information and send impulses to the spinal cord and brain
Interneuron – go between sensory and motor neurons
Motor neurons – go from the brain and spinal cord to the muscles

7. How do impulses move Synapse –a small space that impulses jump across.
Neurotransmitters – chemicals released by the ends of the axons

8. Central Nervous System
Brain and Spinal Cord (CNS)
Brain is broken up into sections
Cerebrum – senses, memory, voluntary muscle control
Cerebellum – coordination, balance and muscle tone
Brainstem – involuntary muscle movement, heartbeat, breathing, etc.

9. Corpus Callosum connects right to left sides of the brain
Cerebrum
Cerebellum
Are you left brained or right brained?

10. Peripheral Nervous System
Nerves that extend from the spinal cord
Somatic – controls your muscles
Autonomic – controls heart beat, digestion and gland functions

11. Reflexes Involuntary and automatic response to stimuli
Reflex Arc – messages are sent from sensory neurons to spinal cord back to motor neurons
Brain movie

12. Senses Light – receptors are eyes
Taste – receptors are taste bud on tongue
Pressure – receptors are in the skin
Temperature – receptors are in the skin
Pain – receptors are in the skin
Vibrations – receptors are ears
Scent – receptors are olfactory cells in the nose

13. Eyes

14. Ear

15. Taste buds