Copyright 2009 Pearson Education, Inc., publishing as Benjamin Cummings Nervous Tissue: Neurons ...

Nervous Tissue: Neurons Neurons = nerve cells

Cells specialized to transmit messages Major regions of neurons

Cell body Processes

Nervous Tissue: Neurons Cell body

Nucleus & large nucleolus, regular organelles except cytoskeleton (*confirms amitotic nature of neurons)

Nissl substance Specialized rough endoplasmic reticulum

Neurofibrils Intermediate cytoskeleton Maintains cell shape

Nervous Tissue: Neurons Processes outside the cell body

Vary in length from microscopic to 3 – 4 feet Dendrites—conduct impulses toward the cell

body Axons—conduct impulses away from the cell

body Axon hillock– cone-like region of the cell body

One axon/cell can have many dendrites (and collateral branches)

Nervous Tissue: Neurons (p. 233)

Figure 7.4

Neuron Processes Cont. Axon Terminal:

Very branched end of axon; contain vesicles with neurotransmitters

Axonal terminals are separated from the next neuron by a gap

Synaptic cleft—gap between adjacent neurons Synapse—junction between nerves

Myelin Sheaths Whitish, fatty material covering axon Functions: protection, insulation, & increasing

transmission rate of impulses Schwann cells—produce myelin sheaths in jelly

roll–like fashion Nodes of Ranvier—gaps in myelin sheath along

the axon Multiple Sclerosis (MS) – myelin sheaths

gradually destroyed & converted to hardened sheaths called scleroses (scar tissue); autoimmune (protein component is attacked)

Nervous Tissue: Neurons

Figure 7.5

Terminology

White Matter = dense collections of myelinated fibers (tracts)

Gray Matter = unmyelinated fibers & cell bodies

CNS PNS

Cell bodies in clusters

Nuclei Ganglia

Bundles of nerve fibers

(neuron processes)

Tracts Nerves

Functional Classification of Neurons Classified according to the direction the nerve

impulse is traveling relative to the CNS Sensory (afferent) neurons

Carry impulses from the sensory receptors to the CNS

Cutaneous sense organs in skin & Proprioceptors in muscles & tendons

Functional Classification of Neurons Cont’d. Motor (efferent) neurons

Carry impulses from CNS to viscera, muscles, or glands

Cell bodies are always in the CNS

Functional Classification of Neurons Interneurons (association neurons)

Found in neural pathways in the CNS Connect sensory and motor neurons

Functional Classification of Neurons

Figure 7.7

Neuron Classification

Figure 7.6

Figure 7.8a

Structural Classification of Neurons Based on # of processes extending from cell body Multipolar neurons—many extensions from the

cell body (ex: motor & association neurons)

Structural Classification of Neurons Bipolar neurons—one axon and one dendrite (rare)

Figure 7.8b

Structural Classification of Neurons Unipolar neurons—have a short single process

leaving the cell body

Figure 7.8c

Copyright 2009 Pearson Education, Inc., publishing as Benjamin Cummings Nervous Tissue: Neurons ...

Documents

Cells and Genes Biology/Psychology 2606. Introduction We touched a teeny bit on neurons and glial cells last time Let ’ s get into it in detail Neurons

Nervous System Chapter 9. Introduction to the NS Neurons – nerve cells Neurons – nerve cells Nerve impulses – electrochemical changes which transmit information

CHAPTER 48 Neurons, Synapses, and Signaling. Neurons Neurons are nerve cells that transfer information within the body. Your brain is made of neurons,

Beyond Neurons: Evidence That Immune and Glial Cells Contribute

12-1 Chapter 12. 12-2 Nervous Tissue Overview of the nervous system Nerve cells (neurons) Supportive cells (neuroglia) Electrophysiology of neurons Synapses

6.5 Neurons and synapses - Pritzker College Prep Freshman … · 2018-03-20 · Synapses are junctions between neurons and between neurons and receptor or effector cells. Only chemical

Anti-Importin 3 NIH3T3 cells Primary hippocampal neurons Mouse ES cells Anti-Importin 1 Anti-Importin 1 NIH3T3 cells Primary hippocampal neurons

Applicability of image analysis of neurons and neuroglia ... · three basic cell types: neurons, neuroglia and endothelial cells. The number, density, volume and morphology of neurons

Cells of the Nervous System Neurons – cells that send signals within the bodyNeurons – cells that send signals within the body Supporting cells: –Glial

Nervous Tissue Two main cell types Neurons Support cells (neuroglial cells)

Floor Plate Issues Diversity – Non-neuronal cells – Neurons Developmental origins Midbrain dopaminergic cells Comparison to insect midline cells

Psychology 210 Cellular Anatomy Lecture 2. Cells of the Nervous System Neurons Neurons Information processing and communicating nerve cells Information

Nervous system - meier.science€¦ · Neurons Basic unit of nervous system All functions involve communication between neurons and with other cells Neuroglia (Glial cells) Regulate

Nervous System. Cell types of Neural tissue Neurons Neuroglial cells

The Nervous System...•The nervous system contains two types of cells: neurons and neuroglia. •Neurons are the cells that transmit nerve impulses between parts of the nervous system

Brain and Behavior Neurons 01.21.2016. W HAT ARE NEURONS ? Cells transmitting info in the nervous system Neurons exist in circuits Group of neurons

TOPIC 6.5 NEURONS & SYNAPSES€¦ · Understandings U1: Neurons transmit electrical impulses. IB BIO –6.5 Key Terms Neurons The nervous sytem is made up of cells called neurons,

Induction of A9 dopaminergic neurons from neural stem cells - Brain

Nervous System Nervous system cells Neurons Glial cells OBJ 43

Pathologic Basis of Disease Neuropathology - 1. Major cells of the CNS Neurons Glial cells: -astrocytes -oligodendrocytes -ependymal cells -microglial