29.2 Neurons Set up Cornell Notes on pg. 39 Topic: 29.2 Nervous System and Neurons Essential Question(s): 1.Draw and label a neuron on pg. 38 in picture bubble map format. 2.1 Atoms, Ions, and Molecules 29.2 Nervous System and Neurons

29.2 Neurons Standard 9.d Students know the roles of sensory neurons, interneurons, and motor neurons in sensation, thought, and response. Standard 9.e Students know the functions of the nervous system and the role of neurons in transmitting electrochemical impulses.

29.2 Neurons The nervous system is a physically connected network of cells, tissues, and organs Controls thoughts, movement, and emotion

29.2 Neurons Ex: Pupils shrinking in sunlight When you go out into the sun your nervous system senses the bright light coming into your eyes and tells your pupils to shrink and let in less light. Try and come up with 2 more examples at your table Senses Reflexes Heart rate Digestion Breathing rate Blinking Sneezing/coughing

29.2 Neurons The nervous system works quickly, using chemical and electrical signals. spinal chord nerves

29.2 Neurons – Central nervous system (CNS) includes the brain and spinal cord –interpret messages from other nerves in the body, and stores some of these messages for later use

29.2 Neurons –Peripheral nervous system (PNS) network of nerves that transmit messages to and from the CNS to other organs in the body

29.2 Neurons Like cable television A physical wire connects your TV. to the cable provider Sends signals through a network of specialized tissues

29.2 Neurons SPONGE 1.Why does your body need a communication system? 2.Which system, the endocrine or the nervous, controls the rate at which you blink? 3.How might a clogged blood vessel affect the endocrine system’s ability to deliver signals?

29.2 Neurons 1.Why does your body need a communication system? A communication system allows the body to respond to its environment and maintain homeostasis 2. Which system, the endocrine or the nervous, controls the rate at which you blink? The nervous system controls the rate of blinking because it controls fast processes. 3. How might a clogged blood vessel affect the endocrine system’s ability to deliver signals? A clogged blood vessel might slow down the delivery of signals by the endocrine system, but not the nervous system

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

29.2 Neurons Cell body Dendrites axon 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) neurotransmitter

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

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

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

29.2 Neurons NEURON Synapse Synapse: Gaps between neurons

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

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

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29.2 Neurons Dendrites of next neuron NEURON

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

29.2 Neurons Cell body Dendrites Draw and label this neuron on p. 38 : axon Myelin sheath Axon terminal NEURON Action potential Neurotransmitters Synapse

29.2 Neurons 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 –Before it can move to the next cell it changes into a chemical signal (neurotransmitter) –You react

29.2 Neurons –Electrical Impulse reaches terminal. impulse terminal

29.2 Neurons –Electrical Impulse reaches terminal. impulse

29.2 Neurons –Electrical Impulse reaches terminal. synapse receptor vesicles impulse neurotransmitter –Neurotransmitters (chemicals) release into synapse.

29.2 Neurons –Electrical Impulse reaches terminal. –Neurotransmitters (chemicals) release into synapse. impulse synapse receptor vesicles neurotransmitter –Neurotransmitters stimulate next cell.

29.2 Neurons Set up Cornell Notes on pg. 41 Topic: 29.2 Types of Neurons Essential Question(s): 1.Neuron Picture Tree Map on pg Function 2.Location 3.Real Example in story format 4.Picture for each (should match story) 2.1 Atoms, Ions, and Molecules 29.2 Types of Neurons

29.2 Neurons There are 3 types of neurons: 1)Sensory neurons 2)Interneurons 3)Motor neurons

29.2 Neurons Sensory Neurons: The dendrites of these neurons act as sensory receptors Gather information by detecting changes inside and outside of the body and sends it to the CNS Function: They gather information and carry impulses into the brain and spinal cord Outside: Light & Sound Intensities Inside: Temperature Oxygen Levels pH Levels

29.2 Neurons 38 1)Interneurons: Receive signals from sensory neurons and relay them within the brain and spinal cord Process and interpret messages

29.2 Neurons 39 1)Motor neurons: Pass messages from the central nervous system to the other tissues in the body, such as muscles Function: Carry nerve impulses out of the brain or spinal cord to effectors Effectors: structures that respond ex: muscles and glands

29.2 Neurons 40 Sensory Neurons Interneurons Motor Neurons Receptors Effectors

29.2 Neurons Spinal Cord 4 5 Label the parts of this reflex arc: Key: Effector Motor Neuron Receptor Interneuron Sensory Neuron

29.2 Neurons 42 1 Receptor 2 Sensory neuron 3 Interneuron 4 motor neuron 5 Effector Spinal cord

29.2 Neurons Give a real life example (Tell a story) Draw a picture for each 43 Types of Neurons Picture Tree Map Sensory Neurons Interneurons Motor Neurons 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 Function Location Function Location Function Location

29.2 Neurons 44 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 In a nutshell….

29.2 Neurons Neurons (nerve cells) are cells that can store information and send and receive messages. In a paragraph, hypothesize how drug or alcohol use might affect neurons?

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

29.2 Neurons 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.