Respiratory System

Respiratory System Chapter 11

Objectives • Identify the organs of the respiratory system • Locate the structures of the respiratory system • Identify the functions of the respiratory system • Review some disorders of the respiratory system • Review some laboratory test and procedures

Functions of the Respiratory System • Breathing process • Exchange of Oxygen and Carbon Dioxide • Enable speech production

How it works: • Consist of a series of tubes that transport air in an out of the lungs. • Function is to supply oxygen to the body cells and to transport carbon dioxide which is produced by the body cells into the atmosphere • There are two forms of respiration exchange

1: External respiration • Oxygen is inhaled (inhaled air is about 21% oxygen) into the air sacs of the lungs • It is then immediately passed into tiny capillary blood vessels surrounding the air spaces

External respiration contd: • Simultaneously, carbon dioxide, ( a gas produced when oxygen and food combine in cells) passes from the capillary blood vessels into the air spaces of the lungs to be exhaled. • Exhaled air contains 16% oxygen • Mostly an involuntary activity

2. Internal respiration • Happens simultaneously as external respiration • Occurs between the individual body cells and the tiny capillary blood vessels • Involves an exchange of gases at the cells with in all organs of the body • Oxygen passes out of the blood stream into tissue cells

Cellular respiration: • Further use of the body cells to use oxygen to produce energy • Release of carbon dioxide and water

FYI: RR = respiratory rate Respiratory rate is the rate per minute of inhaling and exhaling A normal rate for an adult is 16 to 18 times a minute

Structures of Respiratory System • upper respiratory tract • nose, mouth, pharynx, epiglottis, larynx and trachea • lower respiratory tract • bronchial tree and lungs

Respiratory tract divided into:

Upper Respiratory tract: • Nose: (nostrils or nares). • When we inhale air enters the body through the nose via the nasal nares • Then passes trough the nasal cavity • This cavity is lined with mucous membranes and fine hairs called cilia that filter out foreign bodies and also warm and moisten the air

Nose • nasal cavity • nasal septum • mucous membrane • mucus • cilia • olfactory receptors

Upper respiratory contd: • Pharynx (throat) • After passing through the nasal cavity air reaches the pharynx • A 5 inch muscular tube that extends from the base of the skull to the esophagus • The airway that connects the mouth and nose to the larynx

Pharynx: Divided into three sections

Pharynx contd: • Nasopharynx: nearest the nasal cavity and contain adenoids (masses of lymphatic tissue) • If enlarged it can obstruct airway • Equalize pressure on both sides of the tympanic membrane.

Pharynx Contd: • Oropharynx: located behind the mouth • Muscular soft palate that contains the uvula and tonsils.

Pharynx contd: • Laryngopharynx: surrounds the opening of the esophagus • Also known as the hypo pharynx • Serves as a common passageway for food from the mouth and air from the nose • Divided into two branches larynx and esophagus

Pharynx • Nasopharynx • adenoids or pharyngeal tonsils • oropharynx • palatine tonsils • laryngopharynx • larynx

Pharynx: Divided into three sections

Larynx: Voice box • Covered by the epiglottis which is a small flap of cartilage that is attached to the roof of the tongue • Connects the pharynx to the trachea (where air goes down into the lungs) • Contains the vocal cords and is surrounded by nine cartilages for support • Tension of the vocal cords determine the high or low pitch of the voice

Lower Respiratory Tract:

Trachea: Wind pipe • A 10 to 12 cm long tube • Extends into the chest • Serves as passageway for air into the bronchi • Kept open by 16 to 20 C shaped rings made of cartilage • Some of the rings make up the thyroid cartilage forming the Adams apple

Bronchi • Trachea branches into two tubes called bronchi • Bronchi = plural bronchus = singular • Right is primary (main) and shorter than the left • Each bronchus enters the lung and subdivides into smaller tubes • The smallest is called bronchioles

Bronchi contd: • At the end of the bronchioles are clusters of air sacs called alveoli • Alveoli = plural alveolus = singular • Each is lined with a layer of epithelium • This very thin wall permits the exchange of gasses between the alveoli and the capillaries

Lungs: • Located in the thoracic cavity • Right lung has three lobes • Left lung has two lobes • Oxygen passes from the lungs into the capillaries ( network of tiny blood vessels) that surround the alveoli and distributes them to the cells • Carbon dioxide from the blood cells passes into the lungs for removal

Lungs Right-3 lobes Left-2 lobes trachea

Lungs contd: • When oxygen is absorbed into the blood it attaches to the hemoglobin and is released as needed. • Each lung is covered by a membrane called pleura • The outer layer (near the ribs) parietal pleura • The inner layer (closet to the lungs) visceral pleura

Lungs contd: • A serous fluid ( thin, watery lubricating fluid) moistens the pleura • This facilitates movement between the pleuras and prevent friction • Lungs extend from the collar bone to the diaphragm

Lungs contd: • Diaphragm: is a muscular partition that separates the thoracic cavity from the abdominal cavity • This muscles aids in the process of breathing • Breathing is the process of inhalation and exhalation

Lungs contd: • Inhalation: (inspiration) the diaphragm contracts and descends causing enlargement of the thoracic cavity area • This allows air to flow into the lungs to equalize the pressure

Inhalation • Breathing in • Body gets oxygen from the air • Rib muscles contract to pull ribs up and out • Diaphragm muscle contracts to pull down the lungs • Tissue expands to force (pull) in air.

Lungs contd: • Exhalation: (expiration) when the lungs are full, the diaphragm relaxes and elevates making the thoracic cavity smaller • This increases the air pressure in the thorax • Air is then expelled out of the lungs to equalize the pressure

Exhalation • Breathing out • Get rid of carbon dioxide • Rib muscles relax • Diaphragm muscle relaxes • Tissue returns to resting position and forces (pushes) air out

http://users.tpg.com.au/users/amcgann/body/respiratory.html

Respiratory Root Words: • Adenoid/o Adenoids • Alveol/o Alveolus, air sac • Atel/o Imperfect, incomplete • Bronch/o Bronchus • Bronchi/o Bronchial tubes • Epiglott/o Epiglottis • Laryng/o Larynx • Nas/o, rhin/o Nose

Root words contd: • Ox/o, Ox/i oxygen • Pharyng/o throat • Pleur/o Pleura • Pneum/o Lung, air • Pulmon/o Lung • Spir/o To breathe • Thorac/o Chest • Tonsill/o Tonsils • Trache/o Trachea

Respiratory Prefixes: • An-, a- Without, absent • Endo- Within • Inter- Between • Intra- Within

Respiratory suffixes: • -ar, -ary Pertaining to • -capnia Carbon dioxide • -centesis Surgical puncture with needle to aspirate fluid • -ectasis Stretching or expansion • -gram Record • -graphy Process of recording • -itis Inflammation

Suffixes contd: • -ostomy creation of an artificial opening • -oxia oxygen • -pnea breathing • -scope instrument used to examine • -scopy visual examination • -stenosis narrowing or contracting • -thorax chest

Suffixes contd: • -ptysis spitting • -sphyxia pulse • -osmia smell

A few lung disorders: • Lung abscess: a localized collection of pus in a cavity formed by the disintegration of tissue

Asthma • Spasm and narrowing of bronchi, leading to bronchial airway obstruction

Bronchitis • Inflammation of one or more bronchi

Coryza • Profuse discharge from the mucous membrane of the nose

Deviated septum • Defect in the wall between the nostrils that cause partial or complete obstruction

Epistaxis • Hemorrhage from the nose; nose bleed

Hiatal hernia • Protrusion of part of the stomach into the chest through the esophageal hiatus defect of the diaphragm

Pleural effusion • Accumulation of fluid in the pleural space, which compresses the underlying potion of the lung causing dyspnea

Emphysema: • Destruction of alveolar walls

Respiratory System