Reflec Arc Flashcards
What is the simplest type of nervous response?
A reflex arc
What is the central nervous system composed of?
What is the peripheral nervous system composed of?
Central nervous system is composed of the brain and spinal cord. The peripheral nervous system is made up of pairs of nerves that originate from the spinal cord/brain
What is the nervous system split into?
The nervous system is split into the central nervous system and the peripheral nervous system
What is the peripheral nervous system subdivided into?
Sensory neurones and motor neurones
What is the fucntion of the sensory neurones?
The sensory neurones carry nerve impulses from receptors towards the central nervous system
What is the function of the motor neurones?
The motor neurones carry nerve impulses away from the central nervous system to the effectors
What is the motor nervous system divided into?
The voluntary nervous system and autonomic nervous system
What is the function of the voluntary nervous system?
The voluntary nervous system carries nerve impulses to the body’s muscles and is under voluntary (conscious) control
What is the function of the autonomic nervous system?
The autonomic nervous system carries nerve impulses to glands, smooth muscle and cardiac muscle and is not under voluntary control; involuntary (unconscious)
What is the summary of the nervous system?
The nervous system is divided into the peripheral nervous system and the central nervous system
The central nervous system is split into the brain and spinal cord
The peripheral nervous system is split into the sensory nervous system and motor nervous system
The motor nervous system is split into the autonomic nervous system and voluntary nervous system
What is the spinal cord?
The spinal cord is a column of nervous tissue that runs along the back
Where is the spinal cord positioned?
The spinal cord lies inside the vertebral column for protection
What emerges at intervals along the spinal cord?
Emerging at intervals along the spinal cord are pairs of nerves
What type of response is the reflex arc?
The reflex arc is a rapid, short - lived, localised and involuntary response
What is a reflex?
What is a reflex arc?
A reflex is an involuntary response to sensory stimulus
A reflex arc is a pathway of neurones involved in a reflex
What are the main stages of the spinal reflex arc?
1) There is a stimulus - heat from an object
2) A receptor picks up this stimulus - temperature receptors in skin generate nerve impulses in sensory neurone
3) The sensory neurone passes an impulse onto the spinal cord
4) The coordinator (intermediate neurone) links the sensory neurone to the motor neurone in spinal cord
5) The motor neurone carries the nerve impulses from the spinal cord to a muscle in the upper arm
6) The effector, muscle in upper arm, is stimulated so it contracts
7) There is a response elicited that causes the hand to be pull away from the heated object
What is the importance of reflex arcs? (4pts)
a) Reflex arcs do not require the decision making of the brain allowing it to carry out more complex responses
b) Reflex arcs protect the body from harm and are effective from, birth so do not require learning
c) Reflex arcs are fast due to the short neurone pathways that usually have very few synapses
d) The absence of any decision - making allows the reflex arc action to be rapid
