Anaphy

• Respiratory system


  Facilitates the exchange of gases between the air and the blood and between the blood and the body's cells
• Respiratory system


  • Helps us to smell things
  • Helps us to create sound
• Key functions of the respiratory system


  • Breathing (pulmonary ventilation)
  • External respiration (gas exchange in the lungs)
  • Internal respiration (gas exchange in body tissues)
  • Olfaction (smelling)
  • Phonation (sound production)
• Pulmonary ventilation


  1. Air inhaled through nasal and oral cavities

  2. Air moves through pharynx, larynx, and trachea into lungs

  3. Air exhaled back through the same pathway

  4. Changes to volume and air pressure in the lungs trigger pulmonary ventilation

  5. Diaphragm and external intercostal muscles contract during inhalation, causing lungs to expand and air to rush in

  6. Muscles relax during exhalation, causing lungs to become smaller and air to be expelled
• External respiration


  1. Oxygen diffuses from alveoli into pulmonary capillaries

  2. Oxygen binds to hemoglobin in red blood cells

  3. Carbon dioxide diffuses from capillaries into alveoli and is expelled through exhalation
• Internal respiration


  1. Oxygenated blood carries oxygen to body tissues

  2. Oxygen diffuses from capillaries into body tissues

  3. Carbon dioxide diffuses from tissues into blood

  4. Deoxygenated blood carries carbon dioxide back to lungs
• Components of the upper respiratory system

  • Nose and nasal cavity
  • Pharynx
  • Larynx
• Upper respiratory system


  • Allows us to breathe and speak
  • Warms and cleans the air we inhale
  • Mucous membranes trap foreign particles
• Nasal cavities


  • Chambers of the internal nose
  • Air is inhaled through the nostrils and warmed as it moves further into the nasal cavities
  • Nasal conchae swirl the air around to allow it to humidify, warm, and be cleaned before entering the lungs
  • Epithelial cilia and mucous membrane trap unwanted particles
  • Filtered, warmed air passes out of the nasal cavities into the nasopharynx
• Paranasal sinuses


  • Four paired, air-filled cavities found inside bones of the skull
  • Mucosae line the sinuses and help to warm and humidify the air we inhale
  • Mucus formed by the mucosae drains into the nasal cavities
• Pharynx


  • Shaped like a funnel, conducts air between the larynx and trachea and the nasal and oral cavities
  • Includes the nasopharynx, oropharynx, and laryngopharynx
• Larynx


  • Keeps the air passages open during breathing and digestion
  • Is the key organ for producing sound
  • Comprised of nine cartilages, including the epiglottis which closes to steer food down the esophagus
  • Contains the vocal folds which vibrate to produce sound
• Phonation


  1. Air passes from the lungs through the larynx

  2. Muscles in the larynx move the arytenoid cartilages to push the vocal cords together

  3. Air passing between the vibrating vocal cords creates sound

  4. Greater tension in the vocal cords creates higher-pitched sounds, lesser tension creates lower-pitched sounds
• Hyoid bone


  • U-shaped bone located under the chin
  • Only bone in the body that doesn't touch another bone
  • Attached to the tongue and helps with swallowing
  • Serves as attachment points for neck muscles that raise and lower the larynx during speech and swallowing
• Olfaction


  1. Olfactory fibers in the nasal cavities bind to chemicals in the air

  2. Stimulus sends signal from nasal cavities through the ethmoid bone to the olfactory bulbs and then to the olfactory area of the cerebral cortex
• Respiratory system


  • Works in close conjunction with the circulatory system
  • Supplies body cells with oxygen and removes carbon dioxide
• Lungs


  • Cone-shaped, pinkish in color, occupy most of the chest cavity
  • Connected to the trachea which is reinforced by cartilage rings and lined with mucous membrane
• Bronchial cast


  • Resin cast of the bronchial tree, each color indicates an individual bronchopulmonary segment
• Alveoli


  • Microscopic air sacs in the lungs
  • Elastic, thin-walled structures arranged in clumps
  • Macrophages on the inner surfaces ingest and destroy airborne irritants
  • Capillaries around the alveoli allow oxygen and carbon dioxide to diffuse through the alveolar and capillary walls
  • Over 300 million alveoli provide a huge surface area for gas exchange
• Surfactant


  • Natural substance produced by alveolar cells that prevents alveoli from collapsing
  • Consists of fatty substances and proteins
  • Reduces the cohesive forces between fluid molecules lining the alveoli
• Cellular respiration


  • Occurs in every body cell when oxygen reacts with glucose to free its energy
  • End products are carbon dioxide and metabolic water
• Respiratory system


  Facilitates the exchange of gases between the air and the blood, and between the blood and the body's cells. Also helps us to smell things and create sound.
• Key functions of the respiratory system


  • Breathing (pulmonary ventilation)
  • External respiration (gas exchange in the lungs)
  • Internal respiration (gas exchange in body tissues)
  • Olfaction (smelling)
  • Phonation (sound production)
• Pulmonary ventilation


  1. Inhalation through nasal and oral cavities

  2. Air moves through pharynx, larynx, and trachea into lungs

  3. Exhalation through the same pathway

  4. Changes to lung volume and air pressure trigger ventilation

  5. Diaphragm and intercostal muscles contract during inhalation, relax during exhalation
• External respiration


  1. Oxygen diffuses from alveoli into pulmonary capillaries

  2. Oxygen binds to hemoglobin in red blood cells

  3. Carbon dioxide diffuses from capillaries into alveoli and is expelled
• Internal respiration


  1. Oxygenated blood delivers oxygen to body cells

  2. Carbon dioxide diffuses from tissues into blood

  3. Deoxygenated blood carries carbon dioxide back to lungs
• Upper respiratory system


  Nose, nasal cavity, pharynx, larynx. Allows breathing and speech, warms and cleans air.
• Nasal cavities


  • Nostrils allow air inhalation
  • Nasal conchae swirl air to humidify, warm, and clean it
  • Cilia and mucous membrane trap particles
• Paranasal sinuses


  Air-filled cavities in skull bones that help warm and humidify air
• Pharynx


  Funnel-shaped passage for air and food, includes nasopharynx, oropharynx, and laryngopharynx
• Larynx


  Connects pharynx to trachea, keeps air passages open, produces sound
• Epiglottis


  • Closes to steer food into esophagus and away from windpipe
• Vocal folds/cords


  • Vibrate to produce sound during exhalation
• Hyoid bone


  Contributes to respiratory and digestive processes, only bone not attached to another bone
• Olfaction


  Olfactory receptors in nasal cavities detect chemicals, send signals to olfactory bulbs and cerebral cortex
• Respiratory system works with circulatory system to supply oxygen and remove carbon dioxide
• Lungs


  • Cone-shaped, pinkish, occupy most of chest cavity
• Trachea


  Muscular tube reinforced by cartilage rings, lined with mucous membrane
• Bronchial cast shows individual bronchopulmonary segments
• Alveoli


  • Microscopic air sacs where gas exchange occurs
  • Macrophages ingest irritants
  • Surrounded by capillaries
  • Over 300 million alveoli provide large surface area