29.1-2 Nervous System and Neurons Set up Cornell Notes on pg. 31 Topic: 29.2 Nervous System and Neurons Essential Question(s): Draw and label a neuron on pg. 46 in picture bubble map format. 29.1-2 Nervous System and Neurons 2.1 Atoms, Ions, and Molecules KEY CONCEPT The nervous system provides the means by which organ systems communicate and is composed of highly specialized cells.

KEY CONCEPT The nervous system provides one of the means by which organ systems communicate.

The nervous system controls thoughts, movement, and emotion as well as simpler life processes such as swallowing

interconnected network of cells (hardwired) The nervous system works quickly, using chemical and electrical signals. interconnected network of cells (hardwired) signals move through cells (neurons) divided into central nervous system (CNS) and peripheral nervous system (PNS) CNS- brain and spinal cord PNS-network of nerves that transmit messages to and from the PNS to the CNS spinal chord nerves

KEY CONCEPT The nervous system is composed of highly specialized cells.

Make up an information network (Like the internet) Neurons (aka nerve cells) are cells that can store information and send and receive messages within the nervous system. Make up an information network (Like the internet) Cell body axon neurotransmitter Dendrites

A Closer Look at Neurons (4m53s)

Neurons are highly specialized cells. A neuron has three parts. 1. cell body has nucleus and organelles 1 Cell body

Neurons are highly specialized cells. A neuron has three parts. 1. cell body has nucleus and organelles 2. dendrites receive messages from neighboring cells 2 dendrites

Neurons are highly specialized cells. A neuron has three parts. 1. cell body has nucleus and organelles 2. dendrites receive messages from neighboring cells 3. axon carries messages to other cells Specialized support cells- such as the myelin sheath- insulate neurons’ axons and helps them send messages 3 axon

Directions: Please make a picture bubble map of this neuron. Use p Directions: Please make a picture bubble map of this neuron. Use p. 876-879 in your book to help you. Label all major parts of a neuron (cell body, dendrites, axon, myelin sheath, axon terminals, action potential, synapse, neurotransmitters). Once all parts are labeled, you need to describe the function of each.

Synapse: Gaps between neurons

Neurotransmitters: Chemical signals released by neurons Neurotransmitters: Chemical signals released by neurons. Carry information from neuron to neuron. Neurotransmitters

Action Potential: Electrical impulse that carries messages Dendrites receive action potential

NEURON

NEURON

NEURON

NEURON

NEURON

NEURON

NEURON

NEURON

NEURON Dendrites of next neuron

Axon terminal: releases neurotransmitters (chemical signals) Synapse (gap) Axon terminal Dendrites of next neuron

NEURON Check your labels: Neurotransmitters Synapse Cell body axon Myelin sheath Dendrites Axon terminal Action potential

Neurons transmit information in the form of electrical and chemical impulses When a neuron is stimulated, it produces an electrical signal (action potential) within that neuron Electrical Impulse reaches axon terminal

3. Neurotransmitters (chemicals) release into synapse. 2. Before it can move to the next cell it changes into a chemical signal (neurotransmitter) 3. Neurotransmitters (chemicals) release into synapse. 4. Neurotransmitters stimulate next cell. synapse neurotransmitter vesicles receptor

Neurons and Sensory Neurons (2m59s)

How does the structure of a neuron make it effective in carrying out the functions of the nervous system?

How does the structure of a neuron make it effective in carrying out the functions of the nervous system? Neurons have long extensions called axons, which allow messages to be carried long distances without having to pass the signal to another cell.

Set up Cornell Notes on pg. 33 Topic: 29.2 Types of Neurons Essential Question(s): None. 29.2 Types of Neurons 2.1 Atoms, Ions, and Molecules

How the Nervous System Works (1m59s)

There are 3 types of neurons: Sensory neurons Interneurons Motor neurons

1. Sensory Neurons: (Think Senses) Function: Sensory receptors gather information from external/ internal environment and carry impulses along sensory neurons to the CNS NO INTERPRETATION Located in PNS Outside: Light & Sound Intensities Inside: Temperature Oxygen Levels pH Levels

2)Interneurons: Function: Receives signals from sensory neurons and processes and interprets these messages within the CNS Makes decisions on what needs to be done Sends messages/instructions to motor neurons Located in CNS

3)Motor neurons: Function: Carry nerve impulses out of the brain or spinal cord to effectors Effectors: muscles and glands will execute a specific task Located in the PNS.

Motor Neurons (57s)

Key: Motor Neurons Effectors Receptors Sensory Neurons Interneurons 1._______________ Draw/label on p. 33 2. ________________ 3. ______________ 4. _____________ 5._____________

2. Sensory Neurons 3. Interneurons 4. Motor Neurons Key: Motor Neurons Effectors Receptors Sensory Neurons Interneurons 1. Receptors 2. Sensory Neurons 3. Interneurons 4. Motor Neurons 5. Effectors

Key: Motor Neurons Effectors Receptors Sensory Neurons Interneurons 1. 2. 3. 5. 4.

Stimuli and Neurons (4m 16s)

In a nutshell…. The nervous system can: Detect changes in the body Make decisions based on the info received Stimulate muscles and/or glands to respond Counteract changes to maintain homeostasis

Types of Neurons “Story” Tree Map (P. 32) Sensory Neurons Interneurons Motor Neurons Function Location Function Location Function Location Give a real life example (Tell a story) Draw a picture for each 1. The phone rings. The sensory neurons in your ear gather the sound information and send it to the CNS 2. Your brain interprets this information and identifies the sound as the phone ringing. This info is sent to the motor neurons 3. The motor neurons send nerve impulses to your muscles which allow you to answer the phone