Brief History of the and the “ doctrine”

- The Greek era: Hippocrates and Aristotle (300-400 B.C) - The Roman era: Galen (100-200 A.D.) - The Renaissance era: Vesalius, DaVinci, Descarte (1500’s) - The Enlightment era: Bell and Magendie, Gall, Flourens (1800’s) - Turn of the XIXth century: Golgi, Cajal FUN FACTS ABOUT YOUR BRAIN - the human Central (CNS) weighs approximately __3 pounds; largest existing brain is approximately 17__ lbs (sperm whale) - there are approximately ______100 billion in the CNS; that’s 100 000 000 000 !!!!!!!

- each of these neurons makes between ______1000 to ______10,000 connections with other neurons

- number of connections in the cortex alone has been estimated to ______60 trillion

- the size of a neuron varies from ______4 to 100’s of ______micrometers (um)

- length of one of the longest known: 15______feet (from giraffe’s toe to neck) - conduction speed of varies, in different , from ______1 to 250 mph

Chap. 3- 1 NEURON (biological psych definition): ______A very specialized______cell type whose function______is to receive, process,______and send information;______these cells are found______in the central nervous______system (brain, ,______spinal cord) as well as______in the peripheral nervous______system (the rest of the______body). PARTS OF A NEURON:

1. SOMA______or CELL BODY______(

4 5

3 6 7 1 2 Chap. 3- 3 Golgi stain

Golgi stain

Nissl stain

Chap. 3- 4 TYPES OF NEURONS (according to structure):

1. ______Multipolar neuron: more______than two processes ______extending from its cell body.______

AP = where Action impulse Potential is created axon AP

2. ______Bipolar neuron: two processes______extending from the ______cell body. ______AP impulse

axon

3. ______Pseudounipolar neuron:______one process extending ______from cell body. ______

dendrites axon AP impulse

Chap. 3- 5 TYPES OF NEURONS (according to function):

1. SENSORY NEURONS: Neurons______specialized to receive information______from the environment______about what’s out there -______light, sound, pain, temperature, ______pressure, , smell, etc ______and to send this information to the______brain. ______AFFERENT NEURONS (gk – to______carry toward)

2. MOTOR NEURONS: Neurons______specialized to cause movements______(contraction of muscles).______They receive infor- ______mation (“instructions”) from the ______brain (controls voluntary ______movements) and from the body (withdrawal______reflexes, for ______example). EFFERENT NEURONS______(gk – to carry away)

3. or INTRINSIC NEURONS:______Neurons that handle local information;______Ex. Connect sensory to motor information______in the spinal ______cord (withdrawal reflexes), ______Ex. Some cells are contained completely______within the ______cerebral cortex for intracerebral______cortex communication. ______Note: Can also be called projection______neurons.

Chap. 3- 6 Chap. 3- 7 And More Neurons!

Cortical pyramidal neuron seen with Golgi stain NEURAL COMMUNICATION THE : “gap”______between______the presynaptic terminal ______and the neuron it’s trying to “talk”______to.

FUN FACTS ABOUT (gk “to join together”) 1. A synapse occurs ______when one neuron wants to talk to ______.another neuron 2. Types of synapses based on structure: dendrites

(a.)Axo-dendritic ______soma (b.)Axo-somatic ______

(c.) Axo-axonic______axon presynaptic terminals

3. Types of synapses based on neurotransmitter and post- synaptic receptor

Examples: Excitatory synapses - ______Glutamate - ______Aspartate Inhibitory synapses - ______GABA - ______Glycine Modulatory synapses - ______Adrenergic Chap. 3- 8 4. Relational terms: pre-synaptic vs. post-synaptic

5. Gross anatomy of the synapse: (a.) ______axon (h.) ______dendrite (b.) ______mitochondrion (c.) ______synaptic vesicles (d.) ______pre-synaptic membrane (e.) ______synaptic cleft (gap) (f.) ______post-synaptic membrane (g.) ______post-synaptic receptors

Neuron A

impulse

Neuron B

b a c d e f g h

Chap. 3- 9 Synaptic photography! PARTS OF A NEURON : 1. BASIC CELLULAR COMPONENTS - a. CELL MEMBRANE - the “skin” of the neurons; b. CYTOPLASM - everything inside the “skin”

Dendrite: Cell extension that collects information from other cells : Small protrusions on dendrites phat increase surface area Nucleus: Central structure containing the chromosome and genes Nuclear membrane: Membrane surrounding the nucleus

Endoplasmic reticulum: Folded layers of membrane where proteins are assembled Mitochondria: Structure that Golgi body or apparatus: gathers, stores, and releases energy membranous structure that packages protein Intracellular fluid: Fluid in which the molecules for transport cell’s internal structures are suspended Microtubules: Tiny tubes that transport molecules and help give the cell its shape Cell membrane: Membrane surrounding the cell

Axon: Extension that Microfilaments: Lysosomes: Sacs transmits information from threadlike fibers containing enzymes cell body to other cells making up much of that break down wastes the cell’s “skeleton”

Chap. 3-10 General Neuron.

From Kiernan (1998). The Human Nervous System. Fig. 2-5. SUPPORTING CELLS OF THE NERVOUS SYSTEM = ______GLIA

1. : ______cells that form sheat in the ______central nervous system (CNS). ______

2. Schwann cells : ______cells that form myelin______in the ______peripheral nervous system. ______

3. : ______provide structural______support for neurons of the______central nervous system. ______- also provide nutrients to neurons______and regulate chemical ______composition of extracellular fluid.______

4. : ______smallest glial cell and______act as phagocytes to ______protect the brain from invading ______microorganisms. ______- phagocytosis: process by which______cells “engulf” and digest ______other cells or debris caused by ______cellular degeneration.

5. Ependymal cells: ______epithelial cells lining______the ventricles and ______other cavities around the brain, acting______as a barrier; ______- might secrete cerebrospinal fluid,______but in very small ______amounts. ______

Chap. 3-12 Oligodendrocytes and Schwann Cells

Chap. 3-13 Examples of astrocytes in the brain:

Brain photo Cartoon reconstruction Chap. 3-14

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