Respiration 3

Question 1

Give two examples of consciously altering basic breathing rhythm

Answer 1

Hyperventilating and holding breath, both are overridden if necessary

Question 2

What is the role of the dorsal respiratory group and where is it found

Answer 2

Primarily responsible for quiet inspiration - shows periods of activity followed by periods of quiet - length of activity defines how long and deep a breath is - found in the medulla

Question 3

What is the role of the ventral respiratory group

Answer 3

Involved in both inspiration and expiration - not active during quiet inspiration but controls both forced in/expiration

Question 4

What is the role of the pre botzinger complex and where is it found

Answer 4

Found in the ventral respiratory group in the medulla and controls the basic breathing pattern

Question 5

What two centres are found in the pons and what is their function

Answer 5

Pneumotaxic centre - Shortens inspirations to increase the rate of breathing

Apneustic centre - Increases the depth and reduces the rrate by prolonging inspirations

Question 6

What is the Hering Bruer reflex

Answer 6

Stretch receptors in the lung are activated upon over inflation - Vagus nerve fires action potentials to the inspiratory centres in the medulla and apneustic centre in the pons to prevent any more inflation - Phrenic nerve acts on the diaphragm

Question 7

What role do chemoreceptors have on the control of respiration

Answer 7

Central chemoreceptors monitor the cerebro spinal fluid for changes in pH and carbon dioxide
Peripheral chemoreceptors found in the aortic arch and the carotid body are stimulated by a rise in CO2 or a fall in pH or O2, If these receptors are activated then ventilation is increased