Cardio and resp

Question 1

How do the ANS and components interact with the heart?

Answer 1

• the ANS modifies the rate of heart contraction
o the parasympathetic NS innervates the heart via the vagus nerve
♣ causes a decrease in heart rate
o the sympathetic NS innervates the heart via the cervical and upper thoracic ganglia
♣ causes an increase in heart rate
o the adrenal medulla exerts hormonal control via epinephrine (adrenaline) secretion
♣ causes an increase in heart rate

Question 2

o Human body contains an average of four to six litres of blood
o Has both liquid components (55%) and cellular components (45%)

Answer 2

ya