5.1.4 Animal Responses Flashcards
function of neurons
receive and integrate the info arriving via synapse
what does the brain contain
a mass of intermediate neurones
what does the central nervous system consist of
brain and spinal cord
peripheral nervous system
consists of all neurones that connect the CNS to the rest of the body
sensory and motor neurones
what do sensory neurones do
carry nerve impulses from receptors to CNS
what do motor neurones do
carry nerve impulses from CNS to effectors
spinal cord
runs from base of brain through neural canal as far as 1st lumbar vertebrae
central canal
contains cerebospinal fluid which nourishes and maintains electrolyte balance in CNS
meninges
3 membranes which surround brain and spinal cord
help secrete cerebrospinal fluid
Cerebrospinal fluid
fills all spaces inside brain and spinal cord and space between skull bones
helps absorb mechanical shocks to brain
provides nutrients and O2 to brain cells
what are nerves
axon and dendrons arranged in bundles on Peripheral nervous system
how do axons and dendrons enter and leave spinal cord
in spinal nerves
chronical nerves
nerves arising from brain
what are neurones
elongated branched cells specialized for conduction of impulses
what are glial cells
cells that support the neurons in a number of ways
- form insulating sheath
-provide nutrients to neurones
-control composition of fluid surrounding neurones
what does autonomic nervous system do
controls - activity of all smooth muscle
- rate of beating of cardiac muscles
- activity of exocrine glands
- most activities not under voluntary control
2 systems that make up autonomic nervous system and how do the work
sympathetic
parasympathetic
work antagonistically - against each other
sympathetic system
most active at times of stress and increase rates eg HR
fight or flight
parasympathetic
most active in sleep and relaxation
what is noradrenaline
secreted by postganglinomic neurone at synapse between neurone and effector
what is neurotransmitter for sympathetic motor system
noradrenaline
which nervous systems control heart rate
parasympathetic and symathetic
what is neurotransmitter for parasympathetic motor system
acetylcholine
what are the 2 parts of the medulla oblongata
cardiac nerve that icreases HR via sympathetic pathway
Vagus nerve that decreases HR by parasympathetic pathway
what do chemioreceptors detect
change in pH
where are the chemioreceptors located
aorta and carotoid arteries in the neck that take blood towards the brain
where and what info do the chemioreceptors send
send to the cardiac control centre about concentration of CO2, O2 and lactic acid
Baroreceptors
stretch receptors that detect increase in blood flow and blood pressure
what happens when stretch receptors are stimulated
increases HR
where are baroreceptors located
in walls of aorta vena cava and cardiac arteries
