animal responses Flashcards
(25 cards)
Cerebrum
Largest part of brain
Receives sensory input
Processes info
Transmits impulses to effector
Controls voluntary actions
Thoughts
Speech
Emotion
cerebellum
Connects to cerebrum to fine tune motor skills
Balance
Body position
Manipulating tools
medulla oblongata
Controls all involuntary muscles
Autonomic nervous system
Heart rate
Breathing
Swallowing
pituitary gland
Regulates hunger and thrist
Reproductive system (FSH LH)
Osmoregulation ADH
hypothalamus
Controls temperature and osmoregulation via pituitary gland
What is the central nervous system
Brain
Spinal cord
Relay neurones
Coordinates sensory input
What is the peripheral nervous system
Sensory and motor neurones
Send impulses to and from CNS
Attached to effector and sense organs
Which division of the PNS controls voluntary movements
Somatic nervous system
Which division of PNS controls involuntary responses and what is this further divided into
Autonomic nervous system
Divided into sympathetic and parasympathetic
Difference between autonomic and somatic system
AUTO
often unmyelinated
×2 motor neurones
SOMATIC
myelinated
×1 motor neurone
How to sympathetic and parasympathetic differ structurally
PARA
long preganglionic axon
short postganglionic axon
net = ach
SYM
short preganglionic axon
long postganglionic axon
net = noradrenaline at organ
How do sympathetic and parasympathetic affect the body
PARA
at rest
heart rate decreases
breathing rate decreases
increased blood flow to gut
pupils contract
SYM
at stress
increased heart rate
increased breathing rate
increased blood flow to skeletal muscles
pupils dilate
Voluntary skeletal muscle
striated
multinucleate
tires easily
controlled by somatic nervous system
cylindrical shape
Involuntary smooth muscle
unstriated
spindle shaped
one nucleus per cell
controlled by autonomic nervous system
tires slowly
Cardiac muscle
striated
branched
one nucleus per cell
controlled by autonomic nervous system
contracts without tiring
Synaptic transmission
action potential arrives at pre synaptic neurone
Ca2+ ions channel open
Ca2+ ions diffuse into pre synaptic bulb
Vesicles with acetylcholine move and fuse with presynaptic membrane
Acetylcholine released by exocytosis into synaptic cleft
Diffuses across and binds to receptors on post synaptic membrane
Na+ channels open and Na+ diffuse in to create action potential
Name the enzymes that hydrolyse to acetylcholine to prevent constant action potentials occurring
Acetylcholinesterase
Acetylcholine into ethanol acid and chlorine
When an action potential reaches a neuromuscular junction and acetylcholine binds to receptors what happens
Na+ channels open
Na+ Diffuses into sarcolemma
Depolarises T tubule system
Causes sarcoplasmic reticulum to release Ca2+ ions which bind to proposing to start muscle contraction
What do we call a single contracting unit of a myofibril
How does it alter contraction
Sarcomere
I band shortens
Z bands move closer
A band stays the same
Name the proteins found in a muscle sarcomere
Thin actin filaments
Thick myosin filaments
Troponin
Tropomyosin
Describe the sliding filaments theory of muscle contraction
Ca2+ ions from sarcoplasmic reticulum
They bind to troponin
Shape changes causes tropomyosin to move and exposes binding site for myosin head
ATP hydrolysed to reset myosin head in ready position
Myosin head attaches to binding site forming cross bridge
Power strokes move actin over the top of myosin
ADP+Pi released
What is needed to detach the myosin head from the actin to start the process again
ATP binds to myosin head and it detaches from actin
What are the main uses of ATP muscle contraction
To detach myosin head from actin
To actively transport
Ca2+ ions back into sarcoplasmic reticulum
ATP hydrolysed reset myosin head
