Controlling Heart and Breathing Rates

Question 1

parasympathetic nervous system

Answer 1

involves autonomic motor neurones which produce acetylcholine as their neurotransmitter and often often have a relatively slow, inhibitory effect on an organ system; these neurones have long myelinated preganglionic fibres that leave the CNS and synapse in a ganglion very close to the effector organ; postganglionic fibres are very short and unmylelinated

Question 2

sympathetic nervous system

Answer 2

involves autonomic motor neurones which produces noradrenaline as their neurotransmitter and often have a rapid response, activating an organ system; these neurones have very short myelinated preganglionic fibres that leave the CNS and synapse in a ganglion very close to the CNS; postganglionic fibres are long and unmyelinated

Question 2

sympathetic nervous system

Answer 2

involves autonomic motor neurones which produces noradrenaline as their neurotransmitter and often have a rapid response, activating an organ system; these neurones have very short myelinated preganglionic fibres that leave the CNS and synapse in a ganglion very close to the CNS; postganglionic fibres are long and unmyelinated

Question 3

cardiac volume

Answer 3

the volume of blood pumped at each heartbeat

Question 4

cardiac output

Answer 4

a measure of the volume of blood pumped by the heart per minute, calculated by multiplying cardiac volume by heart rate

Question 5

cardiovascular control centre

Answer 5

centre in the medulla oblongata of the brain that receives information from a number of different receptors and controls changes to the heart rate and the cardiac volume through parasympathetic and sympathetic nerves

Question 6

autonomic (involuntary) nervous system

Answer 6

the involuntary nervous system; autonomic motor neurones control bodily functions that the conscious area of the brain does not normally control

Question 7

noradrenaline

Answer 7

neurotransmitter in the sympathetic nervous system and adrenergic synapses of the brain

Question 8

acetylcholine (ACh)

Answer 8

neurotransmitter in the parasympathetic nervous system, the synapses of motor neurones, and cholinergic synapses in the brain

Question 9

baroreceptors

Answer 9

mechanoreceptors in the aorta and carotid arteries that are sensitive to pressure changes

Question 10

adrenaline

Answer 10

hormone produced by the adrenal glands which stimulates the fight or flight response

Question 11

chemoreceptors

Answer 11

sensory nerve cells (or organs) that respond to chemical stimuli