1. Copy everything in RED and draw/label when told to
The Brain and Neurons
Copy everything in RED and draw/label when told to

2. Levels of Organization (copy the pyramid)
Organ systems are living things made of a group of organs that contribute to a specific function within the body.
Organs are living things made of tissues that work together to perform a specific, complex function.
Tissues are living things made of a group of cells with similar structures and functions.
Cells are the smallest unit of life.

3. Types of Tissues
Different tissue types work together within organs:
Muscle tissue (most abundant): controls internal movements of materials (ex: blood, food)
Epithelial tissue: closely packed cells covering the surface of the body and line internal organs (ex: inside chambers of heart, glands)
Connective tissue: holds organs in place and binds different parts of the body together (ex: tendons, ligaments)
Nervous tissue: receives messages from the body’s external and internal environments, analyzes the data, and directs response (ex: controls heart beat)

4. Figure 35-2 Human Organ Systems Part I
Section 35-1
Nervous System
Integumentary System
Skeletal System
Muscular System
Circulatory System

5. Figure 35-2 Human Organ Systems Part 2
Section 35-1
Respiratory System
Digestive System
Excretory System
Endocrine System
Reproductive System
Lymphatic System

6. 11 Functions
Nervous: coordinates the body’s response to change in the internal and external environments.
Integumentary: serves as a barrier against infection and injury, helps to regulate body temperature, provides protection against UV radiation from the sun
Respiratory: provides oxygen needed for cellular respiration and removes excess carbon dioxide from the body

7. Neurons
Messages carried by the nervous system are electrical signals = impulses
Nerve cells that transmit impulses = neurons
Sensory neurons: carry impulses from sense organs to the spinal cord and brain
Motor neurons: carry impulses from the brain and spinal cord to muscles and glands
Interneurons: connect sensory and motor neurons and carry impulses between them

8. Parts of a Neuron
Cell body = largest part containing nucleus and cytoplasm (most metabolic activity occur here)
Dendrites = short, branched extensions spreading out from the cell body and they carry impulses from the environment or other neurons towards the cell body
Axon = long fibers that carry impulses away from the cell body and ends at the axon terminal

9. DRAW and LABEL THIS A Neuron Section 35-2 Nucleus Axon terminals
Myelin sheath
Nodes
Cell body
Axon
Nucleus
Dendrites

10. Synapse
At the end of the neuron, the impulse reaches an axon terminal where the impulse may be passed along to another neuron or another cell
The location where a neuron can transfer an impulse to another cell = synapse
The synapse is a small gap that separates the axon terminal from the dendrites of the next neuron or another cell
The terminals contain tiny sacs or vesicles filled with neurotransmitters = chemicals used by a neuron to transmit an impulse across a synapse
The impulse will continue with the stimulation exceeds the cell’s threshold

11. Dendrite of adjacent neuron
Figure 35-8 The Synapse
Section 35-2
Direction of Impulse
Dendrite of adjacent neuron
Axon
Receptor
Vesicle
Axon terminal
Synaptic cleft
Neurotransmitter

12. Reaction activity
Reaction time = the amount of time required for an impulse travel from your sensory neurons to your motor neurons

13. Brain and Spinal cord Both are protected by bone
wrapped in 3 layers of connective tissue = meninges
layers may have a space between them filled with cerebrospinal fluid which protects (shock absorber) and exchanges nutrients and waste

14. Brain About 100 billion neurons, mainly interneurons
Major parts of the brain:
Cerebrum
Cerebellum
Brain stem
Thalamus
Hypothalamus

15. DRAW THIS35-9 Cerebrum Thalamus Pineal gland Hypothalamus Cerebellum
Section 35-3
Pons
Pituitary gland
Hypothalamus
Cerebrum
Medulla oblongata
Spinal cord
Cerebellum
Pineal gland
Thalamus