Control And Coordination Flashcards
Dendrites
Carries nerve impulse towards cell body
Axons
Carries nerve impulse away from cell body
Some enclosed with myelin shieth
Synapse
Junction between neurons or muscles
Myelin shieth
Insulates axons
Speeds up conduction of nerve impulse
Made or Schwann cells
Nodes of ranvier
Founds between myelin shieth
Types of neurons
Sensory neuron (afferent), relay neurons, motor neuron (efferent)
Reflex arc
Very strong stimulus detected by receptors
Action potential generated in sensory neurons
Sensory neurons connected to spinal cord
Through synapse: action potential passed into relay neurons
Through synapse: action potential passed into motor neurons
Cholinergic synapse of neuromuscular junction
Effectors carry out response
Reflex arc (definition)
Pathway where nerve impulse are carried along during reflex action
Advantages of reflex arc
Fast, involuntary, protects from harm
Impulse
Brief change in charge across membrane
At rest
More negative on the inside than the outside
Resting potential: - 70 mv
When impulses are formed
More positive on the inside than outside
Action potential or depolarization: 30 mv
Roles of receptor cells
- Detects a stimuli
- Acts as transducers
Taste chemoreceptor cells (nacl)
Sodium ions into cell microvilli
Membrane depolarization
Voltage gated calcium ions channel open
Calcium ions enter cells
Triggers movement of vesicles containing neurotransmitters
Neurotransmitters releases
Stimulates an action potential in sensory neurons
Resting potential
Membrane potential is At rest
No impulse formed or transmitted
Inside of axon more negatively charged than outside
Neurons are polarized and maintained at -70 mv