week 5- neuroscience 1

Question 1

describe the divisions of the nervous system

Answer 1

NS to CNS(sensory organs and muscles) to brain and spinal chord (communicates with sensory organs and muscles)
NS to PNS to skeletal nervous to sensory nerves(detect info from physical world to send to brain) and to motor impulses from brain to body(direct muscles to relax or contract)
NS to PNS to autonomic nervous system (receives info from heart and sends comments to heard and other organs) to sensory nerves and motor nerves, from motor nerves to parasympathetic nervous system (promotes rest and digest responses) and sympathetic nervous system (network of nerves that promote a flight or fight response)

Question 2

design the spinal reflex arc

Answer 2

SRA: when sensory neurons, interneurons and motor neurone cooperate to move body away from pain and is controlled at level of spinal cord (brain not directly involved) (ex. when doctor hits knee)
5 elements of SRA: receptor to sensory neurone to integration center to motor neuron to effector

Question 3

explain how the structural and functional features of neurons allow them to process and transmit info (cell body, axon, dendrite, myelin sheath, node of ranvier)

Answer 3

neuron: responsible for transmitting and receiving info through body
glial cells: clear up dead cells, provide neurone with oxygen nutrients protection
nucleus: houses genetic info for cell
cell body: site of production for materials, also contains nucleus
axon: nerve fibre protecting cell body that carries nerve impulse
dendrite: projections that revive impulses from other neurons
myelin sheath: fatty insulating material around axons
node of ranvier: gaps in myelin sheath that helps with impulse conduction

Question 4

name and explain the 3 types of neurons

Answer 4

sensory neurons: carry info towards the CNS
motor neurons: carry impulses away from the CNS
interneurons: forms connection between 2 neurons (ex. between sensory and motor neurons)

Question 5

describe the structure of the neurone and define the action potential

Answer 5

cell body (control center), dendrites (incoming signals), axons (outgoing signals), nucleus, myelin sheath (protects wire thing), axon terminals contain neurotransmitters
Action potential: If neuron successfully depolarized (reaches threshold of activation (-40 to -70 charge)) it will generate action potential and information can pass through one neuron to the next through the synapse and the synaptic cleft (the gate will open for info to pass through), (the potassium and chloride left that did not make it through gate is put back through synapse (reuptake)

Question 6

Describe a synapse and the effects of synaptic transmission

Answer 6

neurotransmitter leaves terminal buttons and crosses synaptic cleft, a synapse is the space between one neuron to the next and space in-between that space is a synaptic cleft
attaches to receptor molecules (key and lock model)
produces excitation or inhibition effects
effects terminated by reuptake or enzymatic breakdown

Question 7

Explain how neurotransmitters affect behavior and mental processes (dopamine, epinephrine, norepinepherine, serotonin, acetylcholine, optoids, GABA, glutamate)

Answer 7

3 families of neurotransmitters that control behavior: amines, amino acids, peptides
Amines:
-dopamine:involved in motivation, punishment and reward
-epinepherine: burst of energy (adrenaline)
-norepinepherine: involved in arousal
-serotonin: regulating mood
-adetylcholine: responsible for motor control
Amino acids:
-optoids: body to cope with pain
-GABA: allows for relaxation (too little GABA=anxiety)
-glutamate: excitatory

Question 8

Describe the ways in which drugs can alter synaptic transmission (2 types of drugs) (3 ways to alter)

Answer 8

2 types of drugs:
-transmitter agonist (enhances neurotransmitter actions)
-transmitter antagonist (blocks/reduces neurotransmitter actions)
3 ways to control:
1) stimulate or inhibit the release of neurotransmitter
2) stimulate or block post-synaptic receptors
3) inhibit reuptake