Biology — The Respiratory System

What is the respiratory system responsible for?

gas exchange between the body and the outside environment

What is the path of air into the lungs?

nose or mouth, then pharynx, larynx, trachea, bronchi, bronchioles, and alveoli

What is the pharynx?

the throat, a tube leading from the nose and mouth

What is the larynx?

the voice box, the passage between the pharynx and trachea

What is the trachea?

the tube connecting the larynx to the bronchi

What are bronchi?

the branches that stem from the trachea into each lung

What are bronchioles?

the smaller airways that branch off the bronchi

What are alveoli?

the tiny air sacs where gas exchange happens

Where in the lungs does gas exchange occur?

in the alveoli

What happens during gas exchange in the lungs?

oxygen moves from the alveoli into the blood, and carbon dioxide moves from the blood into the alveoli

How many lobes does each lung have?

the right lung has three and the left lung has two

What is the cardiac notch?

the dent in the left lung where the heart sits

What is the bronchial tree?

the branching airway structure that looks like an upside-down tree

What is external respiration?

breathing, meaning inhaling air in and exhaling it out

What is internal respiration?

the exchange of oxygen and carbon dioxide between cells and blood

What happens when the diaphragm contracts?

it flattens, the lungs expand, and air is drawn in

What happens when the diaphragm relaxes?

air flows out and the lungs deflate

Is physiological respiration the same as cellular respiration?

no, cellular respiration is how cells make energy, while physiological respiration is breathing and gas exchange

Do we breathe in only oxygen and out only carbon dioxide?

no, air is a mix, and it actually contains more nitrogen than oxygen

Which system does the respiratory system work with to deliver oxygen?

the circulatory system