1. Neurons & The Brain

2. Nervous System Functions
Sensory – gather info from inside and outside the body
Integrative – receive the info and decide what to do about it
Motor – respond to the info

4. Cellular Structure
Neurons – structural and functional unit of the nervous system
Cell Body – nucleus and most organelles
Dendrites – short, highly branched, bring info in
Axon – long, send info away from cell body
Axon terminal – releases neurotransmitter (chemical message to next cell)

5. Neuroglial cells (support cells)
Schwann cells - around axons (PNS)
Produce myelin – a lipoprotein that insulates axon to keep impulses in
Nodes of Ranvier – narrow gaps between Schwann cells

6. Astrocytes – star-shaped, support cells in CNS
Oligodendrocytes – form myelin in CNS

7. Microglial cells – CNS, support, phagocytize bacteria and cell debris
Ependymal cells – covers and lines CNS

8. The Brain
4 Major regions
Cerebrum
Diencephalon
Brain stem
Cerebellum

9. Cerebrum Divided into 2 cerebral hemispheres (left and right)
Makes up half of the brain’s mass
The surface is made of ridges(gyri) and grooves (sulci)

10. Lobes of the Cerebrum
4 lobes, divided by fissures (deep grooves/sulci)

11. Specialized Regions
Somatic sensory area – found at postcentral gyrus, receives impulses from the body’s sensory receptors
Primary motor area – found at the precentral gyrus, sends impulses to skeletal muscles
Broca’s area – involved in our ability to speak

13. Cerebral areas involved in special senses
Gustatory area (taste)
Visual area
Auditory area
Olfactory area

14. Interpretation areas of the cerebrum
Speech/language region
Language comprehension region
General interpretation area

15. Gray matter – outer layer, composed of cell bodies
Layers of the cerebrum
Gray matter – outer layer, composed of cell bodies
Cerebral cortex
White matter – inner layer, composed of axons (myelin makes it white
Cerebral medulla

16. Corpus Callosum
Connects the two hemispheres of the cerebrum
Integrates motor, sensory, and cognitive performances between the cerebral cortex on one side of the brain to the same region on the other side

17. Diencephalon Sits on top of the brain stem, enclosed by cerebrum
Composed of 3 parts
Thalamus
Hypothalamus
Epithalamus

18. The Ventricles
Network of fluid filled cavities in the center of the brain
Contain choroid plexus – produce cerebrospinal fluid (CSF)

19. Thalamus
Receives info and relays to the proper portion of the cerebrum

20. Hypothalamus
Under thalamus
Regulates body temperature, water balance, and metabolism
Connected to the pituitary gland master endocrine gland

21. Houses pineal gland and choroid plexus
Epithalamus
Houses pineal gland and choroid plexus
Pineal gland produces melatonin – regulates sleep cycle (circadiam rhythms)

22. Brain Stem Attaches brain to spinal cord Composed of 3 parts Midbrain
Pons
Medulla Oblongata

23. Midbrain
Tracts of nerve fibers
Reflex centers for vision and hearing
Two bulging fiber tracts – cerebral peduncles

24. Pons
Bulging center portion of brain stem
Mostly fiber tracts
Regulates breathing

25. Medulla Oblongata
Merges with spinal cord
Controls heart rate, blood pressure, breathing, swallowing, vomiting

26. Cerebellum
Regulates coordination, balance, posture, speech, and movement