Chapter 24: The Respiratory System - Respiratory Muscles and Pulmonary Ventilation

Three different reflexes are involved in the regulation of respiration

(1) Mechanoreceptor reflexes, (2) chemoreceptor reflexes, and (3) protective reflexes respond to physical injury or irritation of the respiratory tract.

Chemoreceptor reflexes respond to

change in the PCO2 PH, and PO2 of the blood and cerebrospinal fluid

Mechanoreceptor reflexes respond to

changes in the volume of the lungs or to changes in arterial blood pressure

the internal intercostals .... the ribs and .... the width of the thoracic cavity, thereby contributing to expiration

depress, reduce

Contraction of the .... increases the volume of the thoracic cavity

diaphragm

the external intercostals may assist in inspiration by

elevating the ribs

Before delivery the fetal lungs are

fluid-filled and collapsed.

The pneumotaxic center

inhibits the apneustic center and the inspiratory center in the medulla oblongata

Dorsal respiratory group controls

motor neuron for inspiration

Protective reflexes respond to

physical injury or irritation of the respiratory tract.

The apneustic center (adjust pace of respiration) causes

strong, sustained inspiratory movements

The most important respiratory muscles are

the diaphragm and the external and internal intercostal muscles.

At the first breath

the lungs inflate and never collapse completely thereafter.

Pulmonary ventilation is

the physical movement of air into and out of the lungs.

The respiratory centers are three pairs of loosely organized nuclei in

the pons and medulla.

What is the ventral respiratory group?

The area of the brain stem that is involved in controlling forced expiration.

The pace for respiration is set by

The respiratory rhythmicity center

Conscious and unconscious thought processes can also control respiratory activity by

affecting the respiratory centers or controlling the respiratory muscles