nervous control of heart rate

Question 1

define homostasis

Answer 1

the maintance of an internal state regardless of change in the external or internal conditions

Question 2

what factors in the body are controlled by homostasis?

Answer 2

hypothalamus
evaporation
pancreas regulates blood sugar
skeletal muscles

Question 3

describe the process of negative feedback

Answer 3

receptors = chemoreceptors in the aorta or stretch receptors in the atrial walls
CNS
effectors: SAN in the right atria

Question 4

define autonomic nervous system

Answer 4

part of the nervous system which controls unconscious action

Question 5

define sympathetic nerve

Answer 5

nerves which stimulate action, activating fight or flight

Question 6

define parasympathetic nerve

Answer 6

nerves which inhbit action - prepare the body for resting and digesting

Question 7

what causes an increase in the heart rate?

Answer 7

increase in co2 concentration
reduced o2 concentrations
increased temperature

Question 8

process of responding to exercise – increasing heart rate in response to decreases blood ph

Answer 8

increase in the co2 levels or lactate levels
chemoreceptors in the aorta stimulated
CVC initiates an impluse in the symapathetic nerve
a higher frequency of impluses are transmitted to the SAN
heart rate increased to increase removal of CO2

Question 9

process of responding to exercise – increasing heart rate in response to decreases blood volume

Answer 9

Increase in blood volume and pressure in the right atrium
Stretch and baroreceptors receptors are stimulated
Cardiovascular centre initiate impulses in the sympathetic nerve
A higher frequency of impulses are transmitted to the SAN
Heart rate increased and brings blood volume back to normal