1. WARM UP 11 4/28 Name the organ system.
1. Consists of the peripheral nerves, brain, and spinal cord
2. Function is to coordinate the body’s responses to changes in its internal and external environments
3. Consists of blood, blood vessels, and heart
4. Helps to protect the body from disease
5. Composed of hair, skin, nails, sweat, and oil grands
6. Controls growth, development, metabolism, and reproduction
Put the following in smallest to largest:
7. Individual, cell, organ, tissue, organ system

2. The levels of organization in a multicellular organism from smallest to largest are:
cell→ tissue → organ → organ system

3. Different tissue types work together within organs

4. What is the purpose of each of these items?
Plastic Wrap
Electrical Wire
Packaging Tape

5. What type of tissue is represented by each item?
Plastic Wrap
Electrical Wire
Packaging Tape
epithelial
nervous
connective

6. Behind the scenes, your organ systems are working constantly to do something that few people appreciate- maintain a controlled, stable internal environment
-cells must be kept at a certain temperature
-supply energy through cellular respiration
-clean waste products
Failure at any of these tasks for a few minutes can lead to permanent injury or death

8. Nervous System
Brain
Spinal cord
Peripheral nerves

9. Function: Controls & coordinates functions throughout the body
Responds to internal & external stimuli
Function:

10. Neurons- cells that transmit and carry messages (impulses)
Dendrite
Cell body
Axon terminal
Myelin sheath
Nodes of
Ranvier
Axon
Nucleus
Structure of a Typical Neuron
100 billion neurons in the
brain alone

12. 3 types of neurons Classified by direction impulse travels
1) Sensory neurons- carries impulses from sense organs to spinal cord & brain
2) Motor neurons- brain/spinal cord to muscles
3) Interneurons- connect sensory & motor neurons

13. Nerve impulses are electrical
Resting potential- neuron at rest (negative inside cell)
Action potential- (positive inside cell)
Threshold- minimum level of stimulus to activate neuron

14. Synapse Location neuron transfers an impulse to another cell
Neurotransmitters- chemicals used by neuron to transmit an impulse to another cell
Synapse

16. Page 897 vocab Axon Cell body Myelin sheath Nodes Dendrites
Sketch picture
Label parts
Description for each part
Page 897
Axon
Myelin sheath
Nodes
Cell body
Nucleus
Dendrites
vocab