Chapter 5 - The Biological Basis of Behaviour Flashcards
Central Nervous System vs Peripheral Nervous System
CNS is composed of the brain and spinal cord while the peripheral nervous system is composed of appendages and body.
Components of Central Nervous System
Brain, Spinal Cord, Optic Nerve, Retina
Components of Peripheral Nervous System
Cranial Nerve, Spinal Nerve, Somatic Nervous System, Autonomic Nervous System
Components of nerve cells
Soma, dendrite, axon and axon terminal
Glial Cells
Cells that povide structural support to the brain, 4 different types of glial
Types of Brain Cells
Neurons and Glial Cells
Parts of the synapse
Synaptic Vesicles, Neurotransmitters, Synaptic cleft
Types of neurons
Unipolar, bipolar, Multipolar
Unipolar Neurons
Most simplistic form of a neuron with a singular protrusion, found most commonly in invertebrates
Bipolar Neurons
Neurons with two protrusions image the basic image of a neuron, most common as sensory neurons, who receive a single signal.
Multipolar Neurons
Most complicated and complexe set of neurons that branch off in an indeterminate number of branches, the most common neuron among all of them.
Action potential
Interruoted concentration gradient that falls down the axon of the neuron to send a signal. Potassium enters neuron through voltage gated channels.
Concentration gradient of a neuron
Negative inside neuron positive outside neuron.
Potassium inside neurons, Sodium outside of neurons
Resting potential
The resting voltage that neurons have outside of any action potential around -70 mV
Threshold Potential
The necessary voltage to reach to continue an action potential along the length of the axon the necessary voltage to open the voltage-gated channels. Approx -55 mV
What occurs in the Synapse
The neurotransmitters open up channels that allow the first influx of sodium into the neuron that has a butterfly effect and leads the electrical current down the axon.
Repolarization
Action potential causes potassium channels to open aswell so as the positive sodium enters potassium leaves and rebalances the the charges, at which point sodium-potassium exchange pumps restores the concentration imbalance, the slow closing of the potassium channels causes a refractory period where the neuron can no longer execute am action potential.
Absolute Refractory period
The period in which an action potential is actively taking place and thus another action potential is not possible.
Relative Refractory Period
A brief period of time after an action potential where a large stimulus is required to get the neuron to fire due to hyperpolarization
Strong vs Weak Stimulus
Speed of the Action Potential
Myelin Sheath
A covering of the axon that increases the speed of action potential by only needing depolarization at the nodes of Ranvier. Found normally in the Central Nervous system, White matter has a higher concentration of myelin.
Reflex Arc
The almost instantaneous reaction that uses interneurons inside the spinal cord to react to a stimulus.
Amino Acids
A category of small-molecule neurotransmitters, includes Glutamate and GABA.
Monoamines
A small-molecule neurotransmitter, sub-categories include catecholamines and Indolamines. Neurotransmitters that are synthesized from a single amino acid.
