Chapter 7
Related Combining Forms
espiratory System
Chapter 7
Related Combining Forms
| Structure | Related Combining Forms |
| Nose | nas/o |
| Sinuses | sinus/o |
| Pharynx | pharyng/o |
| Larynx | laryng/o |
| Epiglottis | epiglott/o |
| Trachea | trache/o |
| Bronchi | bronch/o, bronchi/o |
| Alveoli | alveol/o |
| Lungs | pneum/o, pneumon/o, pulmon/o |
Functions of Respiratory System
Delivers air to the lungs
Conveys oxygen from inhaled air to blood
Expels waste products through exhalation
Produces airflow through larynx making speech possible
Structures of Respiratory System
Structures of Respiratory System
Upper respiratory tract
Nose, mouth, pharynx, epiglottis, larynx, and trachea
Lower respiratory tract
Bronchial tree and lungs
Located within and protected by thoracic cavity
Structures of Respiratory System
Nose
Air enters through nose, and passes through nasal cavity
Nostrils
External openings of nose
Nasal septum
Wall of cartilage dividing the nose into two equal sections
Nose
Cilia
Thin hair located inside nostrils
Filter incoming air to remove debris
Mucous membranes
Specialized tissues lining parts of the respiratory, digestive, reproductive, and urinary systems
Nose
Mucus
Secretion produced by mucous membranes
Helps moisten, warm, and filter air entering the nose
Olfactory receptors
Nerve endings acting as receptors for sense of smell
Also important also for sense of taste
Tonsils
Help protect body from infection entering through nose or mouth
Palatine tonsils
Located at back of the mouth
Nasopharyngeal tonsils
Located behind the nose and roof of the mouth
Adenoids
Paranasal Sinuses
(para-: near; nas: nose; -al: pertaining to)
Air-filled cavities lined with mucous membrane
Located in bones of the skull
Three functions
Make bones of skull lighter
Give resonance to the voice
Secrete mucus to lubricate nasal cavity
Paranasal Sinuses
Four pairs
Frontal sinuses
Located in frontal bone just above eyebrows
Infection causes pain in this area
Sphenoid sinuses
Located in sphenoid bone behind eye and under the pituitary gland
Near the optic nerves
Infection may damage vision
Paranasal Sinuses
Maxillary sinuses
Located in maxillary bones under the eyes
Infection causes pain in posterior maxillary teeth
Ethmoid sinuses
Located in ethmoid bone between nose and eyes
Separated from orbital cavity by thin layer of bone
Pharynx
Commonly known as throat
Receives air and food
Three divisions
Nasopharynx
(nas/o: nose; -pharynx: throat)
Posterior to nasal cavity; continues downward toward the mouth
Transports air only
Opens into the oropharynx
Pharynx
Oropharynx
(or/o: mouth; -pharynx: throat)
Visible when looking into the mouth
Shared by respiratory and digestive systems
Transports air, food, and fluids to the laryngopharynx
Pharynx
Laryngopharynx
(laryng/o: larynx; -pharynx: throat)
Shared by respiratory and digestive systems
Air, food, and fluids continue to the opening of esophagus and trachea; air enters trachea; food and fluids enter esophagus
Larynx
Also known as voice box
Located between pharynx and trachea
Supported by nine cartilages; largest is thyroid cartilage (Adam’s apple)
Contains vocal cords that
Separate to allow passage of air
Close to assist with sound production
Protective Swallowing Mechanisms
Two mechanisms prevent entrance of food or water into trachea
Soft palate moves up and backward to close off the nasopharynx
Prevents food from entering the nose
Epiglottis swings downward and closes off the laryngopharynx
Prevents food from entering the trachea and lungs
Trachea
Commonly known as windpipe
Transports air to and from lungs
Located in front of the esophagus
Held open by flexible C-shaped cartilage rings
Allow food to pass down the esophagus
Trachea
Bronchi
Primary bronchi branch from trachea to convey air into the two lungs
Each bronchus divides and subdivides into increasingly smaller bronchioles
Alveoli
Also known as air sacs
Located at the end of each bronchiole
Site of gas exchange
Produce surfactant that reduces surface tension of the fluid in the lungs preventing collapse during exhalation
Lungs
Right lung has three lobes
Upper (superior), middle, lower (inferior)
Left lung has two lobes
Upper (superior), lower (inferior)
Space is restricted due to location of the heart
Lungs
Mediastinum
Middle section of chest cavity
Located between the lungs
Contains connective tissue
Contains organs
Heart and its veins/arteries, esophagus, trachea, bronchi, thymus gland, lymph nodes
Pleura
Moist membrane covering outer surface of lungs and lining inner surface of thoracic cavity
Parietal pleura
Outer layer
Attached to chest wall
Lines thoracic cavity, covers diaphragm, and forms sac containing each lung
Pleura
Visceral pleura
Inner layer
Attached directly to each lung
Pleural cavity (space)
Fluid-filled space between parietal and visceral pleural membranes
Fluid acts as a lubricant
Diaphragm
Muscle separating thoracic cavity from the abdomen
Breathing occurs as diaphragm contracts and relaxes
Contraction stimulated by phrenic nerves
Diaphragm
Respiration
Exchange of oxygen for carbon dioxide
1 inhalation + 1 exhalation = 1 respiration
Inhalation and Exhalation
Inhalation
Breathing in
Diaphragm contracts, and pulls downward; thoracic cavity expands causing vacuum drawing air into lungs
Exhalation
Breathing out
Diaphragm relaxes, and moves upward; thoracic cavity narrows forcing air out of lungs
Inhalation and Exhalation
External Respiration
With inhalation of air into alveoli, oxygen is passed into capillaries and carried by erythrocytes to body cells
Carbon dioxide, as a waste product, is passed into bloodstream and transported into air spaces for exhalation
Internal Respiration
Exchange of gases within cells of blood and tissues
Oxygen passes into cells; carbon dioxide passes into bloodstream where it is transported to the lungs, and expelled during exhalation
Medical Specialties Rel