1. 3.01 Remember the structures of the nervous system

2. 3.01 Remember the structures of the nervous system
Essential Question
What are the structures of the nervous system?
3.01 Remember the structures of the nervous system

3. Introduction: Structures of the nervous system
3.01 Remember the structures of the nervous system

4. Cellular structures of the nervous system
Neuron- a nerve cell
Extensions of the neuron
Dendrites - many
Axon - one
3.01 Remember the structures of the nervous system

5. Cellular structures of the nervous system
Neuron- a nerve cell
Myelin sheath - a special covering of the axon ( it speeds up the impulse along the axon)
Produces a fatty substance called myelin to protect the axon
Synapse – the space between neurons (messages go from the axon of 1 cell to the dendrite of another)
3.01 Remember the structures of the nervous system

6. Membrane Excitability
Nerves carry impulses by creating electric charges
Neurons have a membranes that separate its cytoplasm inside from extracellular fluids outside
Neuron has a lot of K+ but little Na+; opposite of extracellular fluid; membrane allows for these ions to move in and out of the cell
3.01 Remember the structures of the nervous system

7. 3.01 Remember the structures of the nervous system
Membrane Potential
Resting: More positive ions (K+ has moved outside the cytoplasm) on the outside of the membrane (ready for action)
Depolarization: A stimulus is initiated (i.e. sound) that converts to electrical charge which allows the “gated” Na+ ions to come into the cytoplasm (action potential)
Repolarization: the neuron closes to allow no more Na+ but opens the K+ gates to allow it to escape thus sending it back to a positive outside and a negative inside
3.01 Remember the structures of the nervous system

8. Structures of the nervous system
Central nervous system
Brain- cerebral cortex (outer) highest center of reasoning & intellect
Spinal cord
3.01 Remember the structures of the nervous system

9. Structures of the nervous system
Peripheral nervous system
Nerves
Cranial nerves
Spinal nerves
Sensory receptors
3.01 Remember the structures of the nervous system

10. Structures of the central nervous system: BRAIN
3.01 Remember the structures of the nervous system

11. Structures of the central nervous system: BRAIN
Cerebrum: largest part of the brain
Divided into two hemispheres (right and left) by a deep groove called the longitudinal fissure
Frontal lobe
Occipital lobe
Parietal lobe
Temporal lobe
3.01 Remember the structures of the nervous system

12. Frontal Lobe & Temporal Lobe
Controls voluntary muscle movement
Controls speech in the left hemisphere (Broca)
Cells in R hemisphere control movements on L side of the body and vice-versa
Temporal
Anterior portion is smell and the rest is hearing
Wernicke area: central language area for speech understanding & comprehension
3.01 Remember the structures of the nervous system

13. Parietal & Occipital Lobes
Behind the frontal lobe and it is your sensory center
Where you feel pain, touch, heat, cold, and balance
Occipital
Over the cerebellum, visual area that controls eyesight
3.01 Remember the structures of the nervous system

14. Structures of the central nervous system: BRAIN
Diencephalon
Located between the cerebrum and the midbrain
Structures
Thalamus
Hypothalamus
Pineal body
Pituitary gland
3.01 Remember the structures of the nervous system

15. Structures of the central nervous system: BRAIN
Diencephalon
Pineal Body- produces melatonin below the 3rd ventricle
Pituitary Gland-size of a grape, base of brain at the depression of the sphenoid bone; connected to hypothalamus; hormones of pituitary are controlled by hypothalamus
3.01 Remember the structures of the nervous system

16. Structures of the central nervous system: BRAIN
Diencephalon
Thalamus – spherical mass of gray matter; deep in the cerebral hemispheres; relay station for incoming & outgoing nerve impulses
Hypothalamus – lies below the thalamus; part of the limbic system; the “brain” of the Brain
Autonomic Nervous Control
Cardiovascular (BP, constriction & dilation of vessels and heart beat)
Sleep control
3.01 Remember the structures of the nervous system

17. Hypothalamus continued
Temperature maintains 98.6
Appetite control- gives you signals when you are hungry & when to stop eating
Water balance-high osmotic pressure in blood signals water deficiency & ADH is secreted
Manufacture oxytocin-contracts uterus in labor
GI control- increases peristalsis
Emotional State- fear & pleasure
Mind over body experiences- when patients given terminal diagnosis but are able to will themselves well
3.01 Remember the structures of the nervous system

18. Structures of the central nervous system: BRAIN
Limbic system
Located in the center of the brain
Encircles the top of the brain stem.
Olfactory bulb-relates food with emotions
Amygdala-emotional reactor (fear, anxiety, aggression
Hippocampus-memory & learning
3.01 Remember the structures of the nervous system

19. Structures of the central nervous system: BRAIN
Limbic system
Parahippocampus: monitors strong emotions like rage & fright
Fornix: pathway of nerve fibers from hippocampus to mammillary body
Mammillary Body: nucleus transmits messages between fornix & thalamus
Cingulated Gyrus: Modifies Behavior & emotion
Septum pellucidum: connects fornix to corpus callosum
3.01 Remember the structures of the nervous system

20. Structures of the central nervous system: BRAIN
Cerebellum
Controls anything regarding movement of skeletal muscles
Maintenance of balance
Maintenance of muscle tone
Coordination of muscle movements
3.01 Remember the structures of the nervous system

21. Structures of the central nervous system: BRAIN
Brain stem-has gray matter & neurons responsible for sleep-wake cycle; damage to certain area can cause coma
Midbrain-location of cerebral aqueduct assists w/ vision & hearing
Pons-2 way path for incoming and outgoing impulses for both the cerebrum & cerebellum; site of 4 cranial nerves & a respiratory control center
Medulla oblongata-white matter on outside serves as message center between brain & spinal cord; responsible for basic body functions as breathing and heart beat
3.01 Remember the structures of the nervous system

22. Structures of the central nervous system: BRAIN
Meninges
Dura mater
Outermost layer- Lines inside of skull; tough fibrous material that has an abundant amount of blood vessels
Arachnoid
Middle layer- cobweb of fluid filled spaces
Pia mater
Innermost layer- covers the brain surface itself
CSF fills space between arachnoid and pia mater (produced within the ventricles & is our brain’s
shock absorber)
3.01 Remember the structures of the nervous system

23. Structures of the central nervous system: BRAIN
Ventricles - lined cavities deep within the brain
filled with cerebrospinal fluid
Choroid plexus – rich network of blood vessels in all 4 ventricles of the brain; aids in formation of CSF
Is selective in its ability to allow certain things to pass through (blood brain barrier)
3.01 Remember the structures of the nervous system

24. 3.01 Remember the structures of the nervous system
Brain Teasers
3.01 Remember the structures of the nervous system

25. 3.01 Remember the structures of the nervous system
What word do you see?
Read aloud
3.01 Remember the structures of the nervous system

26. 3.01 Remember the structures of the nervous system
Can you read this?
3.01 Remember the structures of the nervous system

27. Structures of the central nervous system: Spinal Cord
Surrounded by the vertebrae, meninges, and cerebrospinal fluid
3.01 Remember the structures of the nervous system

28. 3.01 Remember the structures of the nervous system
Spinal Cord Anatomy
Grey Matter: route sensory or motor stimulus to interneurons of the CNS in order to create a response to the stimulus through chemical synapse activity.
White Matter: It contains nerve fibers. Many of these nerve fibers (axons) are surrounded by a type of fat called myelin. The myelin gives the white matter it's color. Myelin acts as an insulator. It plays an important role in the speed of nerve signaling.
3.01 Remember the structures of the nervous system

29. Structures of the peripheral nervous system:
Afferent peripheral nerve system: sensory neurons that send info from receptors in the periphery of the body to the brain & spinal cord
Efferent peripheral Nerve System: motor neurons send info from brain & spinal cord to muscles & glands
Somatic: impulses from CNS to skeletal muscles (voluntary)
Autonomic: impulses from CNS to smooth muscle (involuntary)
1. Sympathetic: “fight or flight”
2. Parasympathetic: “rest & digest”
3.01 Remember the structures of the nervous system

30. Structures of the peripheral nervous system
I. Olfactory
II. Optic
III. Oculomotor
IV. Trochlear
V. Trigeminal
VI. Abducens
VII. Facial
VIII. Vestibulocochlear
IX. Glossopharyngeal
X. Vagus
XI. Accessory
XII. Hypoglossal
Cranial nerves
3.01 Remember the structures of the nervous system

31. 3.01 Remember the structures of the nervous system
Structures of the PNS
Peripheral nervous system
31 pairs of spinal nerves
Named by location in the spinal cord (plexus: network of nerves in spine)
Cervical Plexus (C1-C4): mvmt of shoulders & neck
Brachial plexus (C5-8, T1): mvmt shoulder, wrist & hands
Lumbar Plexus (T12, L1-4): mvmt of buttocks, anterior thigh & leg
Sacral Plexus (L4-5, S1-2): motor mvmt leg (sciatic nerve: lgst nerve in body—gluteus maximus to knee)
3.01 Remember the structures of the nervous system

32. 3.01 Remember the structures of the nervous system
Structures of the PNS
Anterior View
Peripheral nervous system
12 cranial nerves
31 pairs of nervous
Posterior
view
3.01 Remember the structures of the nervous system

33. 3.01 Remember the structures of the nervous system
Structures of the PNS
Motor system
Autonomic nervous system
Sympathetic nervous system
Parasympathetic nervous system
Somatic nervous system
3.01 Remember the structures of the nervous system

34. Structures of the PNS Autonomic nervous system
Sympathetic nervous system
Extends from the base of the brain, along both sides of the spinal column
These nerves connect to all internal organs
Parasympathetic nervous system
The vagus nerve connects the medulla with organs of the upper body
The pelvic nerve emerges from the spinal cord and connects with the organs of the lower body
3.01 Remember the structures of the nervous system

35. Structures of the PNS Somatic nervous system
These nerves are located along the spinal cord.
Connect skeleton, muscles and joints to the brain.
3.01 Remember the structures of the nervous system

36. Structures of the CNS & PNS
Check your knowledge…
3.01 Remember the structures of the nervous system

37. Structures of the nervous system
Remember this!
3.01 Remember the structures of the nervous system

38. 3.01 Remember the structures of the nervous system
Essential question
What are the structures of the nervous system?
3.01 Remember the structures of the nervous system