Animal responses Flashcards
sympathetic nervous system
many nerves out CNS leading to separate effectors ganglia just outside CNS short pre-ganglionic neurones long post-ganglionic neurones noradrenaline as neurotransmitter
parasympathetic nervous system
few nerves out CNS, divide and lead to diff effectors ganglia in effector tissue long pre-ganglionic neurones short post-ganglionic neurones acetylcholine as neurotransmitter
cerebrum
higher mental processes conscious thought memory actions emotional responses decisions reasoning
cerebellum
movement - contraction of skeletal muscles
balance/maintain body position
judge position of objects/limbs
hypothalamus
homeostatic responses
controls physiological processes
medulla oblongata
controls autonomic responses
association areas
compare sensory input with previous experience and judge appropriate response
pituitary gland
acts with hypothalamus
posterior lobe linked to hypothalamus by specialised neurosecretory cells (hormones made in hypothalamus pass down this to be released to blood from pituitary gland)
anterior lobe produces hormones released in blood in response to releasing factors from hypothalamus
medulla oblongata
controls non-skeletal muscles
cardiac centre regulates heart rate
vasomotor centre regulates circulation/blood pressure
respiratory centre regulates rate/depth of breathing
cranial reflex
passes through part of the brain but doesn’t involve thought processes in higher parts of the brain
corneal reflex
sensory neurone in cornea, AP enters myelinated neurones in pons
AP to sensory region in cerebral cortex to inform higher centres of brain and allow reflex to be overridden by conscious control (inhibitory signal to motor centre in pons)
how can an inhibitory AP prevent AP in motor neurone in corneal reflex?
myelinated neurones from/to cerebral cortex more rapid than non-myelinated relay neurone in pons
when activity is increased in sympathetic NS, where are hormones released from?
anterior pituitary gland
process of adrenaline taking effect
adrenaline binds to receptors on plasma membrane associated with G protein
G protein activated which activates adenyl cyclase
adenyl cyclase catalyses ATP to cyclic AMP (cAMP) which acts as the secondary messenger causing enzyme action
hormones form the anterior pituitary gland
hypothalamus secretes releasing factors (enzymes) which pass down portal vessel to pituitary
stimulate release of tropic hormones from anterior part which stimulate endocrine gland activity
