Respitory system

• The human function of the respiratory system


  1. Take in oxygen (inhalation)

  2. Expel carbon dioxide and other minor gases (exhalation)

  
• Function of the Lungs

  • Carry out the exchange of gases during the breathing process
• What is the Respiratory process

  1. Red blood cells collect oxygen from the lungs and carry it to all parts of the body

  2. Red blood cells collect carbon dioxide and transport it back to the lungs

  3. Carbon dioxide leaves the body when we exhale
• What is Hypoxia

  Decrease in oxygen
• What is Anoxia

  Complete lack of oxygen
• If four minutes pass without the ingress of oxygen to the lungs then hypoxia and anoxia can be fatal, and brain cells begin dying, which can lead to brain damage and death
• What is a Newborn child's normal breathing rate

  Approximately 40 times each minute, may slow to 20 to 40 times per minute when sleeping
• Organs involved in the respiratory system

  • Nose
  • Pharynx
  • Larynx
  • Trachea
  • Bronchi
  • Lungs

  
• Average respiratory rate for adults

  12 to 16 breaths per minute when resting, up to 45 breaths per minute during strenuous exercise
• Nose


  • External meatus: triangular-shaped projection in the center of the face
  • External nostrils: two chambers divided by the septum
  • Septum: made up mainly of cartilage and bone, covered by mucous membranes
  • Nasal passages: lined with mucous membranes and tiny cilia (hairs) that filter the air

  
• Types of sinuses


  • Ethmoid sinus
  • Maxillary sinus
  • Frontal sinus
  • Sphenoid sinus
• Pharynx


  • Fibro muscular tube with a semicircular cross section, extends from the base of the skull to the lower border of the cricoid cartilage
  • Six muscles responsible for the voluntary actions of the pharynx

  
• Nasopharynx


  • Located between the base of the skull and the soft palate, continuous with the nasal cavity, performs a respiratory function by conditioning the inspired air and then propagating it into the larynx, lined with respiratory epithelium, contains the adenoid tonsils

  
• Oropharynx


  • Middle area of the pharynx, located between the soft palate and the superior border of the epiglottis, contains the posterior 1/3 of the tongue, lingual tonsils, palatine tonsils, superior constrictor muscle, and Waldeyer's ring, involved in the voluntary and involuntary phases of swallowing

  
• Laryngopharynx


  • Most distal part of the pharynx, located between the superior border of the epiglottis and inferior border of the cricoid cartilage, continuously inferior to the oesophagus, contains the middle and the inferior pharyngeal constrictors
• Pharynx


  Continuation of the digestive cavity, route from the oral cavity to the esophagus, communicates with the nasal cavity, middle ear cavity, and larynx

  
• Larynx


  • Tough, flexible segment of the respiratory tract, connects the pharynx to the trachea, allows the open passage of air while keeping food and drink from blocking the airway

  
• Trachea


  • Wide hollow tube, connects the larynx to the bronchi of the lungs, provides air flow to and from the lungs to enable respiration, located along the body's midline, anterior to the oesophagus and just deep from the surface of the skin

  
• Bronchi


  1. First bronchi are the right and left main bronchi, which enter the lungs

  2. Further branching develops into secondary bronchi (lobar bronchi) and tertiary bronchi

  3. Bronchi continue branching until the sixth generation, after which they become bronchioles
• Bronchioles


  • Tubular structures around 1mm in diameter, consist of connective tissues and smooth muscles to keep them open, further divide into smaller tubules that continue subdividing until they reach the alveoli
• Alveoli


  • Tiny air sacs in the lungs that take up the oxygen in the air breathed in, expand to take in oxygen when breathing in, shrink to expel carbon dioxide when breathing out
• Lungs


  • Two spongy, pinkish organs situated in the chest, the right lung has three lobes, the left lung has two lobes to make room for the heart, begin at the bottom of the trachea

  
• Bronchioles


  • Tubular structures around 1mm in diameter
  • Consist of connective tissues combined with some smooth muscles that act to keep these tiny tubes open
  • Further divide into smaller tubules, which in turn continue subdividing until they reach the alveoli
  • The bronchioles are the final and finest (smallest internal diameter) tubes in the passage of air from the nose to the lungs

  
• Alveoli


  The tiny air sacs in the lungs that take up the oxygen in the air breathed in

  
• Alveoli


  • Expand to take in oxygen when breathing in
  • Shrink to expel carbon dioxide when breathing out
• Lungs


  • Two spongy, pinkish organs situated in the chest
  • The right lung is made up of three lobes
  • The left lung has only two lobes in order to make room for the heart

  
• Respiratory system


  1. Ventilation: moving the air in and out of the lungs

  2. Diffusion: the oxygen-carbon dioxide exchange

  3. Perfusion: pumping blood through the lungs

  
• Diaphragm


  • A thin skeletal muscle that sits at the base of the chest, separating the abdomen from the chest
  • Contracts and flattens during inhalation, creating a vacuum effect that pulls external air into the lungs
  • Relaxes during exhalation, pushing air out of lungs
• Openings in the diaphragm

  • Esophageal opening: the esophagus and vagus nerve pass through
  • Aortic opening: the aorta and thoracic duct pass through
  • Caval opening: the inferior vena cava passes through
• Respiratory system disorders


  • Obstructive conditions: emphysema, bronchitis, asthma attacks
  • Restrictive conditions: fibrosis, sarcoidosis, alveolar damage, pleural effusion
  • Vascular diseases: pulmonary oedema, pulmonary embolism, pulmonary hypertension
  • Infectious, environmental and other diseases: pneumonia, tuberculosis, asbestosis, particulate pollutants

  
• Coughing is of major importance, as it is the body's main method to remove dust, mucus, saliva, and other debris from the lungs. Inability to cough leads to infection.
• The respiratory tract is permanently exposed to microbes. This is due to the extensive surface area; it is why the respiratory system includes many mechanisms to defend itself and to prevent pathogens from gaining entrance to the body.
• Common respiratory system disorders

  • Chronic Obstructive Pulmonary Disease (COPD)
  • Chronic Bronchitis
  • Emphysema
  • Asthma
  • Pneumonia

  
• Chronic Obstructive Pulmonary Disease (COPD)

  An irritation of the lungs that can lead to asthma, emphysema, and chronic bronchitis
• Chronic Bronchitis


  Irritants stimulate an increased secretion of mucus, clogging up the air passages
• Emphysema


  The delicate walls of the alveoli break down, reducing the gas exchange area of the lungs
• Asthma


  Periodic constriction of the bronchi and bronchioles makes it more difficult to breathe
• Pneumonia


  An infection of the alveoli, caused by many kinds of both bacteria and viruses, where tissue fluids accumulate in the alveoli reducing the surface area exposed to air
• Common word roots


  • adren - adrenal
  • arteri - artery
  • aur - ear
  • arth (ro) - joint
  • brachi - arm