animal respones Flashcards
(28 cards)
2 different type of nervous systems
Central
Peripheral
what does the CNS consist of
brain and spinal cord
relay neurone
synapse
PNS features
contains sensory and motor neurones
detects stimuli
nerves go from sense organs to glands
what does PNS break down to
Somatic
Autonomic
role of somatic ns
conscious control
role of autonomic ns
subconscious control
what does autonomic ns branch into
sympathetic
parasympathetic
role of sympathetic ns
noradrenaline is the neurotransmitter
fight/flight
role of parasympathetic ns
acetylcholine is the neurotransmitter
rest and digest
role of cerebrum
controls voluntary action such as learning memorising and conscious thought
role of cerebellum
controls unconscious functions such as posture and balance
role of medulla oblongata
used in autonomic control
controls heart rate and breathing rate
role of pituitary gland
stores and releases hormones that regulate many body functions
e.g FSH LH GH
role of hypothalamus
regulatory centre for body temperature and balance of water potential
reflex arc features
involuntary
causes faster response preventing or minimising damage to the body
knee jerk reflex
when the leg is tapped beneath the knee cal it stretches the patellar tendon which stimulates the quadriceps muscle to contract and the hamstring muscle to relax causing the leg to extend
blinking reflex
occurs when the cornea is stimulates and the eye lid closes preventing anything from entering the eye
importance of reflex
involuntary response
doesn’t need to be taught so available from birth
it’s fast as it only involves like one or two synapses
how change in blood pH changes blood pressure
increases metabolic activity cause more carbon dioxide to be produced by tissues
this reduces blood pH which is detected by chemoreceptors
sends impulses to medulla oblongata centre
activates sympathetic nervous system
increases frequency of impulses send to SAN
SAN increases heart rate
increases the blood pressure so more carbon dioxide is removed
how blood pressure is increased
low bp is detected by baroreceptors in blood vessels
sends impulses to medulla oblongata centre
activates sympathetic NS
impulses send down accelerator nerve to san
increases the frequency of wave of excitation from SaN
increases heart rate
how blood pressure is reduced
high bp is detected by baroreceptors
sends impulses to medulla oblongata centre
activates parasympathetic ns
impulses send down vagas nerve to SAN which causes a decrease in the frequency of wave o excitation from SAN
decreases heart rate
features of skeletal muscle
responsible for movement under conscious control
regular arrangement of muscle fibres so contracts in one direction
multinuckeated
straited due to bands of actin and myosin
short contraction length
rapid contraction
features of cardiac muscles
found in heart
involuntary control
faintly straited
contains branches cells
uninucleated
intermediate contraction length and speed
myogenic
smooth muscles
involuntary control
non straited muscle
uninucleated
spindle shaped
contracts more slowly
no regular arrangement