1. Chapter 7:6
The Nervous System

2. Key Terms Autonomic Nervous System Brain Central Nervous System
Cerebellum
Cerebrospinal Fluid
Cerebrum
Diencephalon
Hypothalamus
Medulla Oblongata
Meninges
Midbrain
Nerves
Nervous System
Neuron
Parasympathetic
Peripheral Nervous System
Pons
Somatic Nervous System
Spinal Cord
Sympathetic
Thalamus
Ventricles

3. The Nervous System
Neuron (nerve cell) – the basic structural unit of the nervous system
Consists of:
Cell body (soma) – contains the nucleus
Dendrites – nerve fibers (carries impulses towards the cell body)
Axon – single nerve fiber (carries impulses away from the cell body)

4. The Nervous System (Axons)
Many axons have a lipid covering called a myelin sheath
Increases the rate of impulse transmission
Insulates and maintains the axon
The axon of one neuron lies close to the dendrites of other neurons
Synapses – the spaces between one neuron and the dendrites of another
Impulses “jump” the synapses to reach the next dendrite
Neurotransmitters (a special chemical) are located at the end of each axon

5. Draw and Label Your Own Neuron
To Label:
Axon
Cell Body (Soma)
Dendrites
Myelin Sheath
Terminal Branches

6. Central Nervous System (brain and spinal cord)
Main Structures of the brain:
Cerebrum – the largest and highest section of the brain
Responsible for reasoning, thought, memory, judgment, speech, sensation, sight, smell, hearing, and voluntary body movements
Cerebellum – section below the back of the cerebrum
Responsible for muscle coordination, balance, posture, and muscle tone

7. Central Nervous System (brain and spinal cord)
Main Structures of the brain:
Diencephalon – section located between the cerebrum and midbrain, contains the thalamus and hypothalamus
Thalamus – allows conscious recognition of pain and temperature
Hypothalamus – regulates and controls the ANS, temperature, appetite, water balance, sleep, and blood vessel dilation and constriction. Also involved in emotions.

8. Central Nervous System (brain and spinal cord)
Main parts of the brain:
Midbrain – located below the cerebrum at the top of the brainstem
Conducts impulses for certain eye and auditory reflexes
Pons – located below the midbrain and in the brainstem
Responsible for certain reflex actions such as chewing, tasting, and saliva production; also helps with respiration
Medulla Oblongata – lowest part of the brainstem
Responsible for regulating heartbeat, respiration, swallowing, coughing, and blood pressure

9. Draw and Label Your Own Brain
To Label:
Cerebellum
Cerebrum
Frontal Lobe
Medulla Oblongata
Midbrain
Occipital Lobe
Parietal Lobe
Pons
Temporal Lobe

10. Central Nervous System (brain and spinal cord)
Continues down from the medulla oblongata and ends at the first or second lumbar vertebrae
Meninges – cover and protect the brain and spinal cord
Dura Mater – thick, tough, outer layer
Arachnoid Membrane – middle layer that is delicate and weblike
Subarachnoid Space – contains cerebrospinal fluid
Pia Mater – innermost layer that is closely attached to the brain and spinal cord – provides nourishment to the nerve tissue

11. Peripheral Nervous System
Consists of:
Somatic Nervous System:
12 pairs of cranial nerves
Some cranial nerves are responsible for special senses
Other cranial nerves receive general sensations such as touch, pressure, pain, and temperature
31 pairs of spinal nerves
Carry messages to and from the spinal cord
Each nerve goes directly to a particular part of the body

12. Peripheral Nervous System
Consists of:
2. Autonomic Nervous System
Helps to maintain a balance in the involuntary functions of the body
Allows the body to react in times of emergency
1. Sympathetic Nervous System
Fight or flight response (increasing heart rate, respiration, and blood pressure, slow the digestive system
2. Parasympathetic Nervous System
After the emergency, it returns the body to normal