Name:
Marieb ch. 13 Respiratory system
Name the organs forming the respiratory passageway from the
nasal cavity to the alveoli of the lungs and describe the function of
each
Nasal Cavity: where air enters through nose, sense of smell
Pharynx: common passageway for air and food
Larynx: routes air and food into the proper channels and serves as
the “voice box” for speech
Trachea: “windpipe”, cilia in trachea propels mucus away from
lungs to throat, where it can be swallowed or spat out
Lungs (primary bronchi): air chambers
Bronchioles: conducts air to the alveoli
Alveoli: “air sacs” where gas exchange takes place
Describe the several protective mechanism of the respiratory
system
Respiratory mechanismsIntrapulmonary volume- decrease in gas pressure in lungs
causes a vacuum drawing air into the lungs
forced expiration- intercostal muscles are activated to help
depress rib cage, abdominal muscles contract and help to force
air from lungs by squeezing abdominal organs upward against
diaphragm
Atelectasis (lung collapse) - presence of air in intrapleural
space, disrupts fluid bond between pleurae called
pneumothorax, reverse by drawing air out of intrapleural space
with chest tubes, allows lung to reinflate and resume its normal
function
Nonrespiratory air movementsCough- taking deep breath, closing glottis, forcing air against
glottis, glottis opens suddenly, blast of air rushes upward
Sneeze- same as cough but forced air is directed through nasal
cavities instead of through oral cavity
Crying- inspiration followed by release of air in a number of short
breaths
Laughing- same as crying in terms of air movements produced
Hiccups- sudden inspirations resulting from spasms of diaphragm,
sound occurs when inspired air hits vocal folds of glottis
Yawn- very deep inspriation
Show the pathways for the flow of oxygen starting with the lungs
and ending with alveolar sac.
Lungs (primary bronchi) → bronchioles → alveoli duct → alveoli →
alveolar sac
Describe the process of gas exchanges in the lungs and tissues
and how gases are transported in the blood, include any necessary
muscles.
Volume change lead to pressure changes, which lead to flow of
gases to equalize pressure
Inspiration- when muscles of diaphragm and external intercostals
contract, size of thoracic cavity increase, rib cage is pushed
upward, residual air in lungs is pushed into larger spaces of lungs,
this causes a decrease in the gas pressure which creates a vacuum
drawing air in
Expiration- diaphragm and external intercostals relax, thoracic and
intrapulmonary volumes decrease which causes gas pressure to
increases pushing gases in lungs more closely together, pressure
becomes greater than atmospheric pressure, to equalize pressure,
air is released
Gas exchange- connections of alveoli sacs and capillary tubes
from circulation system, carbon dioxide diffuses out of capillary
tubes into alveoli sacs, oxygen diffuses into capillary tubes from
aveoli, oxygen attaches to RBC using a protein called hemoglobin
Which part of the brain controls respiration?
Pons and Medulla of brain control breathing, nerve impulses
trigger contraction of muscles through the intercostal and phrenic
nerves, oxygen sensor in artery (aortic arch) indicates an oxygen
decrease and carbon dioxide decrease
Define the following:
Apnea: breathing stops, until carbon dioxide builds up in blood
again
Dyspnea: difficult or labored breathing, often referred to as “air
hunger”
Hyperventilation: state of breathing faster and/or deeper than
necessary, thereby reducing the carbon dioxide concentration of
the blood below normal
Hypoventilation: occurs when ventilation is inadequate
chronic obstructive pulmonary disease (COPD) including
symptoms and probable causes:
Symptoms: dyspnea, coughing and frequent pulmonary infections,
hypoxic, respiratory failure
Emphysema- alveoli enlarge, lungs become less elastic, airways
collapse during expiration, obstruct airflow of air
Chronic Bronchitis- mucosa of lower respiratory passages
becomes severely inflamed produces excess amounts of mucus,
mucus impairs ventilation and gas exchange, increases risk of
infections and pneumonias
Causes: airborne pathogens and/or smoking
Label the attached diagram of the respiratory system.