Overview
At the most basic level, the body is run by neurons. These cells link together to provide sensory information and trigger muscle movements.
Each neuron is a cell with all the regular functions. It’s cell body (soma) has a nucleus, DNA, RNA, mitochondria and all the standard cell components.
Neurons have some additional structure components and a very different functional component.
Structurally, neurons typically come with extensions. The dendrites look like ginger covered with spiny bristles. Neurotransmitters bind to the receptors of the dendritic spines, so dendrites are important for inputs.
The other extensions are axons. They are the outputs of neurons.
Neurons are amazing. Functionally, they are living batteries that discharge quickly, recharge and discharge again. There are factories to produce the needed components, tubes to carry products, and pumps and gates to manage its climate.
Pay particular attention to how neurons are formed and how they are aided by glia.
Learning Objectives
By the end of this module, you should be able to:
- Compare and contrast neurons and glia.
- Explain the importance, structure and functions of the blood-brain barrier.
- Describe the properties of a semipermeable membrane.
- Compare and contrast resting- and action-potentials.
Readings:
- Kalat C1
- Neural Anatomy
- Neural Impulse
Slides:
Videos:
Discussion Question:
What happens if the sodium channels of a neuron don’t open?
Quiz (not the same as on Canvas)
Written Assignment:
For items 1 and 2, give a short but thorough summary of the factor or concept.
For item 3, describe what you found difficult or confusing in this section. If nothing was difficult or confusing, describe what you found most interesting.
At the bottom, list at least two sources in APA format (including retrieval date if it is a website). The book can be one of them but you are not limited to using it.
- Where is the blood-brain barrier and what does it do?
- Contrast and compare the absolute refractory period and the relative refractory period.
- What did you find difficult or confusing in this section? If nothing was difficult or confusing, what did you find most interesting?
Study Aids:
Key Terms
- absolute refractory period
- action potentials
- active transport
- afferent axons
- all-or-none law
- astrocyte
- axon
- blood-brain barrier
- cell body
- concentration gradient
- dendrite
- dendritic spines
- depolarize
- efferent axons
- electrical gradient
- endoplasmic reticulum
- glia
- glucose
- graded potential
- hyperpolarization
- interneuron
- intrinsic neuron
- local anesthetic
- local neurons
- membrane
- microglia
- mitochondria
- motor neuron
- myelin
- myelin sheath
- myelinated axons
- neuron
- nodes of Ranvier
- nucleus
- oligodendrocytes
- polarization
- presynaptic terminal
- propagation of the action potential
- radial glia
- refractory period
- relative refractory period
- resting potential
- ribosomes
- saltatory conduction
- Schwann cells
- selective permeable
- sensory neuron
- sodium-potassium pump
- thiamine
- threshold
- voltage-gated channels
Links:
- Life and death of a neuron (Links to an external site.)
- Neural impulses (Links to an external site.)
Summary:
Most cells keep to themselves but neurons are show offs.They love to talk to each other (chemically speaking). A neuron can’t live without interacting with other neurons.
