Respiratory System Flashcards
What is cellular respiration?
Inspired O2 is used by cells as energy to conduct specific cellular functions.
What is the primary function of the respiratory tract?
To conduct inspired O2 around the body to cells for gaseous exchange and remove Co2 in expired air.
What are the main components of the upper respiratory tract?
Nose, nasal cavity, pharynx and larynx
What structures make up the lower respiratory tract?
Trachea, bronchi and bronchioles, lungs, diaphragm and alveoli
Where are the nasal turbinates located and what is their function?
Scrolls of bone located in the nasal cavity, made of ciliated epithelial cells. They trap dust and particles as well as warming inspired air to protect the lungs.
What are the 2 divisions of the pharynx? What are their functions?
Nasopharynx and Oropharynx. Conducts air to the trachea and food to the oesophagus.
What is the function of the larynx?
Regulates the flow of gases into the respiratory tract and prevents the aspiration of food into the lungs.
How does gaseous exchange occur in the alveoli?
Oxygen in inspired air diffuses across the pulmonary membrane and into bloodstream within capillaries. Carbon dioxide diffuses out of the blood and into the alveoli to be expired in air.
Why does diffusion occur during gaseous exchange?
There is a higher concentration of oxygen within the inspired air and lower in the blood in capillaries. There is a higher concentration of carbon dioxide in the blood and lower in the air.
How do bronchioles differ from bronchi?
Smaller divisions which are narrower with less cartilaginous support. Continue to divide into smaller passages before reaching alveolar ducts.
What is the purpose of smooth muscle in the walls of bronchi and bronchioles? What system does this relate to?
Allows respiratory passages to dilate and for a greater volume of air to enter the lungs. This relates to the autonomic nervous system.
What happens to the diaphragm during exhalation?
Diaphragm moves up and thoracic muscles relax, causing chest cavity to get smaller and push air out the respiratory system.
What adaptations do birds have to their respiratory systems? How is this suited to enable flight?
They have air sacs with unidirectional air flow, moving in one direction ensuring a constant oxygen supply and maximising gas exchange. Enhances metabolic processes needed for flight.
How do fish breathe with gills underwater?
Oxygen-rich water is inhaled through the mouth, pumped over the gills and diffuses into the capillaries where the circulatory system supplies it to all tissues and cells. Co2 leaves through gills.
What are spiracles?
respiratory openings found in the abdomen and thorax of insects. They contain hemolymph for carrying oxygen which diffuses into the body.
