respiration Flashcards
what are the components of the upper respiratory tract?
nose, pharynx, and associated structures.
what are the components of the lower respiratory tract?
larynx, trachea, bronchi and lungs.
what is the most superior part of the respiratory tract?
the nasal cavity.
where is the pharynx and what does it do?
part of throat behind mouth and nasal cavity, caries air to larynx.
what does the larynx do?
It is involved in breathing and producing sound, protects trachea from food aspiration.
Known as the voice box.
Describe the trachea.
Is a cartilagenous tube connecting larynx to the bronchi of the lungs.
Describe bronchus/bronchi
conducts air to lungs, no gas exchange at this point.
Branches off at trachea to left and right, becoming narrower in lungs.
what is the most important organ in respiratory system
the lungs.
where are lungs found in the body ?
near backbone, either side of heart above diaphragm.
where is the site of gas exchange in the respiratory system & describe it.
the lungs, extract oxygen from air, transfer to the blood. then carbon dioxide is released from blood to atmosphere.
what is the pleurae?
covers the lung, lubricates and reduces friction between lung and chest wall.
list the functions of the respiratory system.
1)Provision of O2
2)Elimination of CO2
3)Regulate pH of blood (homeostasis)
4)Phonation (sound production: singing, speaking)
5)Protection against microbes & environmental variations (dehydration, temperature changes)
6)Emotional expression (laughing, crying)
7)Muscles of respiratory system assist in abdominal compression during urination, defecation & childbirth
8)Provide olfactory sensations.
name the 5 steps of respiration.
1) ventilation
2) gas exchange
3) gas transport
4) gas exchange
5) cellular respiration.
how does air get in and out of lungs ?
air moves bc of pressure differences. high to low
what Is Boyles law?
Gas law, states that pressure of a gas is proportional to its volume.
what muscles elevate ribs and sternum during inhalation?
external intercostals, pectoralis minor and scalenes ,neck, increase size of thoracic cavity.
what muscles depress ribs and sternum during active expiration?
internal intercostals, abdominal muscles decrease size of thoracic cavity.
what muscles depress ribs and sternum during passive expiration?
elastic lung recoil, elastic fibres in alveolar wall, surface tension of fluid film lining alveoli.
air movement results from different between what?
atmospheric pressure (760mmHg) and alveolar pressure P alv (inside alveolus) decrease = air moves into lungs.
what is the pleural cavity?
the space between lung and chest wall.
what happens if P ip (inside pleural cavity) is less than P alv?
alveoli expands.
what happens if air enters the pleural cavity?
alveoli cannot expand, lungs collapse. called pneumothorax
what factors affect rate of pulmonary airflow.
surface tension of alveolar fluid.
lung compliance - capacity for stretching
Airway resistance - controlled by pressures and airflow.
what is the role of surfactant in lung ?
decreases surface tension of alveoli to prevent them from collapsing.
