An Intro To The Nervous System Flashcards
What are the functional divisions of the nervous system?
Sensory division (afferent) → CNS → responding motor division (efferent)
↓
somatic (voluntary) → autonomic (involuntary) → sympathetic division
→ parasympathetic division
What are the two key cell types of the nervous system?
- neurones
- glial cells
What is the function of glial cells?
- support neurones and allow them to function
What is the function of neurones?
- responsible for communication (action potential/ neurotransmission)
Why are neurones described as specialised cells?
Transmit information as electrical
signals - nerve impulses or action
potentials (AP)
What is apart of the structure of a neurone?
➢main part = cell body/ soma
➢dendrites (extension of cell membrane) = receive information from other cells
➢single axon = divides to communicate with other cells
➢many axons = wrapped by insulating substance (myelin sheath)
➢gaps = nodes of ranvier 9deposited by glial cells)
➢ nucleus
Which types of glial cells produce myelin?
Oligodrendrocytes (CNS) and
Schwann cells (PNS)
What do astrocytes CNS (glial cells) do?
Enable homeostasis, physical
barrier/connector, buffer, reuptake of
neurotransmitters support neurones
What do microglia CNS (glial cells) do?
- immune cells of the brain
- in charge of phagocytose dead cells and debris
What do ependymal CNS (glial cells) do?
- help form barriers to prevent things from getting into the nervous system
What is a nerve?
- a bundle/ collection of neurones
What are the 4 receptor types/ families?
*ligand-gated ion channels (ionotropic)
*G-protein coupled receptor
(metabotropic)
*Kinase linked receptor
*Nuclear receptor
What are some properties of synapses?
✿ may be excitatory
✿ may be inhibitory
✿ use different neurotransmitters
✿ allow different ions to travel through their channels
What are some examples of excitatory neurotransmitters?
*GLUTAMATE
*acetylcholine
* monoamines
*dopamine, noradrenaline, 5HT/ seratonnin
What are some examples of inhibitory neurotransmitters?
- GABA
- Glycine
- Endorphins
What are some examples of neuromodulaters?
– Neuropeptides
– Endocannabinoids
CNS brain structure: What is the cerebrum?
part of brain for higher functions
- contains cortex + sub cortex = movement, memory and emotion
What is the diencephalon?
important for homeostasis
* between brain stem and cerebrum
* contains hypothalamus and pituitary
What is the brain stem and functions?
involuntary functions,
blood pressure, breathing, vomiting,
sleep/arousal
What is the function of the cerebellum?
- co-ordinates movement
what is the structure of the cerebrum’s cortex?
- 2 hemispheres joined by corpus callosum
- surface folded
What is the frontal lobe for?
reasoning, planning, speech,
movement, problem solving
What is the parietal lobe for?
movement / orientation
recognition, stimuli perception
What structures protect the brain?
- cranium
- meninges (membranes)
What are the three meninges membranes?
- Dura mater (outer)
- Arachnoid membrane
- Pia mater (inner)
What is between the arachnoid membrane and Pia mater?
the cerebro spinal fluid (CSF)
What are the functions of the CSF?
- Protection
- Physical: buoyancy and padding
- Chemical: Stable ionic environment.
- Different to plasma
- No blood cells little protein
