Coordination and Response Flashcards
what are stimuli?
stimuli are changes in an organisms environment which we detect using receptors
what are three examples of reflexes and describe their purpose
the pupil reflex - pupils get smaller in bright light to regulate the amount of light which enters the eye,
the blink reflex- eyes blink when there is near movement to potentially protect the eyes from damage,
the swallowing reflex - makes it harder to swallow straight after having swallowed just before, to prevent the throat from over filling and therefore preventing choking
what part of the hand is most sensitive and why?
the palm of the hand is most sensitive as this area is designed to detect stimuli as the palm of the hand has more receptors than the other parts.
what are the 5 sense organs
skin, tongue, nose, eyes, ears
what is the stimulus for skin
pressure, pain, temperature
what is the stimulus for tongue
chemicals in food and drink
what is the stimulus for nose
chemicals in the air
what is the stimulus for the eyes
light
what is the stimulus for ears
sound
what is the central nervous system
- the central nervous system (CNS) is made up of the spinal cord and the brain.
- the peripheral nervous system carries information to or from the CNS
- when a stimulus is detected by a receptor, impulses (messages) pass down neurones to the CNS which then sends more impulses out along neurones to an effector which causes a response.
what is a reflex
a reflex is an automatic and rapid response, such as when you touch something hot or sharp.
draw a diagram of the reflex arc
include:
- sensory neurone
- motor neurone
- relay neurone
- spinal chord
- impulse
- receptor
- effector
what are neurones
- specialised cells which make up nerves
- sensory neurones carry impulses from sense organ to CNS
- relay neurones are found inside the CNS and connect sensory and motor neurones
- motor neurones carry impulses from the CNS to effectors (muscles or glands)
label a diagram of a sensory and motor neurone
MOTOR NEURONE:
- dendrites
- nucleus
- cell body
- axon
- electrical impulse
- insulating sheath
SENSORY NEURONE:
- dendrites
- nucleus
- cell body
- axon
- electrical impulse
- insulating sheath
what are synapses
- the gaps between neurones are called synapses
- the impulse is transmitted from one side to the other using neurotransmitters, which travel across the gap via diffusion
- synapses mean that nerve impulses are unidirectional, meaning they only travel in one direction
- they can also connect more than one neurone