NEUROTECH OVERVIEW Flashcards
What is the main functional unit of the nervous system?
Neurons
What type of cells supports neurons?
Glial cells
How many connections are there in the brain?
over 100 trillion
How are messages relayed to the brain?
via the spinal cord
What structures are included in the central nervous system (CNS)?
The brain and the spinal cord
What are the characteristics of the tissue present in the CNS? What helps to “counteract” this?
Soft and delicate - so we have the skull and the spinal vertebrae
what prevents toxins from entering the brain?
The blood-brain barrier (BBB)
How does the CNS interact with the PNS?
The CNS will send information (motor info) to the PNS. In turn, it will receive sensory information from the PNS.
What protects the PNS?
Nothing really, it’s exposed to toxins and injury.
What type of information is afferent?
Sensory
How does afferent information conduct?
Inwards [PNS —> CNS]
What type of information is efferent?
Motor
How does efferent information conduct?
Outwards [CNS —->PNS]
What is the somatic system?
Conscious activity to and from the CNS
What is the autonomic system?
Unconcious/ involuntary activity to and from the CNS
Somatic sensory system?
info from the senses to the CNS
Somatic motor system?
info from the CNS to the PNS (like controlling the skeletal muscles)
Autonomic sensory system?
Visceral (organ) info to the CNS
Autonomic motor system?
CNS to systems/visceral
What is the sympathetic nervous system and what is it a subsystem of?
It’s a subsystem of the Autonomic motor division. Fight or flight. Increased HR breathing. Dilated pupils. Decreased digestion
What is the parasympathetic motor system and what is it a subsystem of?
It’s a subsystem of the autonomic motor division. Rest and digest. Increased digestion, decreased breathing and HR. Also slow to kick in.
What are receptors?
Part of the sensory division. Receive information about the changing environment
What are effectors?
Part of the motor division. Produce changes in the body that can in turn effect the outside world.
What 3 components do all neurons have
- Soma (cells body) 2. Dendrites 3. Axon/s
What are dendrites?
Short extensions that conduct E signals inwards towards the soma
What are Axons?
Short or long extensions that conduct E signals outwards away from the soma
How long is the longest Axon? Where is it?
1 meter or around 3 feet (base of the spine to ankle)
What is a synapse
The gap where electrochemical information/interactions occur between 2 neurons. Usually axon to dendrite
What can happen to a cell which isn’t apart of the nervous system, but interacts with a neuron?
Any cell that receives a synaptic signal from a neuron may be excited, inhibited, or otherwise modulated.
What are the 6 steps of “normal” electrochemical communication between two neurons
- E signal will travel down one neuron’s axon
- Neurotransmitters are released at the axon terminal
- These neurotransmitters will bind to the channels on one dendrite of the other neuron
- The channels on the dendrite will open to receive positively charged ions from the synapse (Na+, Ca+, etc)
- If the change in membrane voltage is enough, an action potential will occur
- This action potential causes the neuron to send an electrical signal down its own axon
What is the function of Glial Cells?
They take care of and support neurons and their connections
List some types of Glial Cells.
- Astrocytes
- Oligodendrocytes
- Ependymal Cells
- Schwann cells
- Satellite cells
- Microglial Cells
