Biological Basis of Behavior

FAU course summer 2025 PSB3002

Sensory neurons

detects changes in the internal or external
environment.

Motor neurons

control muscular contractions to create movement (behavior)

Interneurons

connect sensory and motor neurons in the CNS; as well as form local circuits and relay neurons in the brain and CNS

Interneurons are also known as

relay neurons

Nerves

bundles of individual nerve fibers or axons, especially in the PNS mostly mixed nerves

Dendrites

have many branches that receive input from other neurons

postsynaptic cell

somatic or dendritic membrane of the receiving cell

Axoplasmic (Axonal) Transport

How Proteins and other molecules are synthesized in the cell body
(soma) and moved down the axon

Anterograde (Orthograde) transport

The movement of materials made in the soma toward the terminal buttons; uses energy (ATP)

Kinesin

a molecular motor or protein that transports materials down microtubules

kinesin rate of transport

Rate of transport about 500 mm/day

Retrograde transport

Movement of materials from terminal buttons towards the soma; requires energy (ATP)

Retrograde transport’s molecular motor/protein called

Dynein

Dynein rate of transport

Rate of transport about 250 mm/day

Glial Cells

support cells for neurons found in the central nervous system (CNS)– 3 type

Astrocytes

Provide physical support and nutrients to neurons and controls chemical environment around neuron

Oligodendrocytes

Produce the myelin sheath around axons in
the CNS,

myelin sheath is

80% lipid: 20% protein

Oligodendrocytes myelinate

multiple places on a single axon and multiple axons myelinated by one

Node of Ranvier

the space on an axon between segments or tubes of myelin; an exposed axon

Microglia (amoeboid-like)

Act as phagocytes/scavengers, Protect the brain from invading organisms — immune system function

Schwann Cells

Each segment of myelin is produced by one _____ cell
wrapping around an axon