Homeostasis Part 5

Neuron

nerve cell that conducts ner impulses, communication via neurons is called neuron singaling

4 components of neural singaling

Receprion, transmission, intergration, and response

3 types of neurons

Afferent neuron, interneuron, Efferent neuron

Afferent neuron

are sensory neurons, carry indo to receptors (skin, eyes, ears) to central nervous system

Interneuron

intergrate information

Efferent neuron/ Motor neurons

carry response signal/carry singals from central nervous systems to muscle and gland for action

Neuron characteristics

vary widely in shape and size, all have enlarged bodies and have 2 extensions and processes

Axons…

are bundled together and from nerve fibers

Neuronal circuit

connections between the axon terminals of one neuron and the dendrite of another

Glial cells

they don’t conduct electrical signals, the provide nutrition and support

Schawnn cells

Form tightly packed layers of plasma membranes (myelin sheaths) around axons

Nodes of Ranvier

allows diffustion to happen, are the gaps between schawnn cells and expose the axon, and speeds the rate of electrical impulse of movement

Central Nervouse System

Made of interneurons, is made uo of the brain and spinal cord and is the centre for mechanical and chemical actions

Peripheral nervous system

subsystem that communicates with the central nervous system, is composed of the afferent system and efferent system

Efferent system

controls motor activities of the body, is made up of th somatic systme and the autonomic system

Somatic system

responsible for control of voluntary body movements via skeletal muscles and for processing sensory information like touch and pain

Autonomic system

controls involuntary processes like breathing, heart rate and digestion, is further divided into sympathetic system and parasympathetic system

Sympathetic system

Increases energy production consumption and is the body’s flight or fight response, activates when stressed or in danger, increases heart rate and and enlarges pupils

Parasympathetic system

activates after a period of stress or danger and is the body’s “rest and digest” state, conserves energy and reduces body activities like reducing heart rate and constricts pupils

Reflex arc

the simplest neural circuit, doesn’t require the brain to respond first

Interneurons connected to…

the reflex circuit also send signals to the brain that makes you aware of the stimulus that caused the reflex

exmaples of the reflex arc working

delay in feelings of pain due tp extra tiem required for the impulses to travel to the brain