Coordination and Response Flashcards
(27 cards)
Electrical impulses travel….
along neurones
define Central Nervous system
The central nervous system consists of the brain and spinal cord
define Peripheral nervous syystem
the peripheral system nervous system consists on nerves outside the brain and spinal cord
Role of nervous
the role of the nervous system is in the regulation and coordination of body function
state Simple reflex arc
receptor, sensory neurone, relay neurone, motor neuron and effector
define Simple reflex action
A simple reflex action is a means of automatically and rapidly intergrating and coordinating stimuli for the response of effectors
roles synapse
is a junction between neurones
it ensure impulses travel in one direction
Events at a synapse
an impulse stimulates the release of neurotransmitter molecules from the vesicles into the synaptic gap and the diffuse across the gap and bind on to the protein receptors on the next neurone and an impulse is stimulated on the next neurone
define Sense organs
sense organs are a group of receptors cells that respond to specific stimuli being light, tempereture, sound, touch and chemicals
Function of cornea
refracts light
Function of iris
controls how much light enters the pupil
Function of lens
focuses light onto retina
What happens during a Pupil reflex
in dim light the cirular muscles relax and the radial muscles contracts and the pupils widens increases in diametre to allow more light to enter when in bright light the circular muscles contract and the radial muscles relax and this causes the pupil to contract and to shrink in diametre to allow less light in
what happens in Accomadation
when an object is far the ciliary muscles contract and the pressure cause the suspensory ligaments to tighten and this causes the lens to become thinner and lesss light is bent. When an object is close the ciliary muscles relax and the lack of pressure causes the the suspensory ligament to slacken and this inturn causes the lens to become fatter or thicker and more light is bent
Rods are…
for night vision
what is fovea
the fovea is an area on the retina where almost all of the cone cells are found
what is hormone
is a chemical substance produced by glands that is carried in the blood that alters the activity of one or more target organs
what happens when u have Adrenaline
fast heart rate
higher glucose concentration
fast breathing rate increased pupil diametre
compare nervous system to hormonal
nervous system is faster
hormonal lasts longer
impulses carried in neurones where as hormones carried in blood
Define homeostasis
this is the maintenance of a constant internal enviroment
describe how glucose levels are controled
when glucose levels are high this change is detected and the hormone inslulin is excreted by pancreas and it stimulates the liver to convert excess glucose in the blood to gylcogen whic is to be stored when glucose levels are low the change is detected and glucagon is released to stimulate the liver to convert stored glucose glycogen in glucose to be released into the blood
treatment for type 1 diabeties
insulin shot
execise to regulate glucose
when you are hot what happens?
sweat is secretd by sweat glands
hairs lie flat on the skin allowing air to freely circulate as more heat will be lost to enviroment
vasodilation more blood pumped into arterioles
when u have low tempereture whats happens
we shiver
the hairs on our skin trap a layer of air which acts as insulatores
vasoconstriction
