Respiratory System Parts and Function PDF

Respiratory System RESPIRATORY SYSTEM Respiratory System: a group of organs that provides living things with oxygen from the outside the body and gets rid of wastes such as carbon dioxide Respiration vs. Breathing Common Misconception: ▻ “Respiration is the same thing as breathing” Respira...

Respiratory System RESPIRATORY SYSTEM Respiratory System: a group of organs that provides living things with oxygen from the outside the body and gets rid of wastes such as carbon dioxide Respiration vs. Breathing Common Misconception: ▻ “Respiration is the same thing as breathing” Respiration: all of the processes involved in bringing oxygen into the body, making it available to each cell, and eliminating CO2 as waste 4 STEPS IN FOR HUMANS RESPIRATI ON  1.BREATHING *For Humans* -inspiration and expiration Inspiration - breathing in or inhaling oxygen rich air into lungs Expiration - breathing out or exhaling waste air from lungs  2. EXTERNAL RESPIRATION This is the exchange of gases between *lungs* and *blood* such as O2 and CO2 This stage of the respiratory process performs the vital function of gas exchange. Gas exchange - is the delivery of O2 from the lungs to the blood, and the elimination of CO2 from the blood to the lungs. 3. INTERNAL RESPIRATION The exchange of gases (O2 and CO2) between *blood* and *body’s tissue cells*  4. CELLULAR RESPIRATION Cellular respiration (inside mitochondria) Cellular respiration is the series of energy- releasing chemical reactions that take place within the cells. It is the sole means of providing energy for all cellular activities.  Composition of Air We Breathe What is the air in our atmosphere made of? ▻ 78% Nitrogen (N2) ▻ 21% Oxygen (O2) ▻ 1% CO2 and Trace Elements (e.g., Argon) ▰ Myth: We breathe in pure O2 and breathe out pure CO2  General Functions of the Respiratory System PRIMARY function: BREATHING (for gas exchange) ▻ intake of oxygen needed by the cells ▻ release of carbon dioxide produced by the cells (remove waste, maintains pH balance of blood) ▰ Also used to produce SOUND.  Human Adaptations For efficient gas exchange to occur: 1. Water must be present respiratory at the respiratory surface surface: so that the gases are dissolved in water the area of an - Respiration should animal’s body happen in a moist environment where gases are exchanged with 2. The respiratory surface the environment must be large enough so In humans, the lungs are the main organs of respiration. - However, lungs are located deep within the body, a suitable passageway is necessary for air to move from outside the body to the respiratory surface inside the body. - This passageway is called the respiratory tract.  Human Respiratory System Lower Upper Respiratory Respiratory ▰ Bronchi ▰ Nose & Mouth ▰ Bronchioles ▰ Pharynx ▰ Aveoli ▰ Epiglottis ▰ Pleural ▰ Larynx ▰ Trachea membrane Nasal cavity Path taken by air Path taken by food Part Functi Structure on Human Respiratory System 1- Point of Septum – separates nostrils Nasal entry Mucus – moisture and sense passa of smell ges Filter, Cilia (hairs) – prevent large (Nose) warm, substances from entering. and Capillaries moiste Sinus cavities – produce ns air mucus Turbinates – tiny bones that increase surface area. 2- Oral Warms Alternate space for gas Cavity and exchange, but no filtration (Mout moiste Part Function Structure 3- Human Respiratory Connects nasalSystemCilia in top Pharynx and oral cavity to portion move larynx food towards mouth to be swallowed Epiglotti A flap that Small, flexible s prevents food from flap of tissue entering the lungs by blocking the glottis (opening of trachea) Part Function Structure 4- Human Respiratory Contains System the vocal chords Two flaps of cartilage, Larynx – for sound, aka “voice vibrate when air passes box”. through Opening to lungs “Adam’s Apple” – a thick band of cartilage that surrounds and protects the larynx. LARYNX: During normal breathing, muscular tissue holds the vocal cords apart, allowing air to pass freely through the larynx. To make sounds, the vocal cords are moved closer together so that pressure from air expelled from the lungs causes the cords to vibrate. The pitch of the sound varies with the length of the vocal cords. Diagram of Larynx Part Function Structure Human Respiratory System 5- From larynx, ~10-12cm long Trachea air moves from throat to into trachea middle of chest into 2 bronchi, Semicircular “windpipe”. loops of Filter cartilage rings particles to prevent collapse -Cilia and mucus  Nasal Cavity Path taken by air Upper Path taken by food Pharynx Respirator Larynx Epiglottis Esophagus y Trachea Tract  Human Respiratory System Lower Upper Respiratory Respiratory ▰ Bronchi ▰ Nose & Mouth ▰ Bronchioles ▰ Pharynx ▰ Alveoli ▰ Epiglottis ▰ Pleural ▰ Larynx ▰ Trachea membrane  Our Lungs The trachea (windpipe) branches into two tubes called bronchi (similar to upside down trees). ▰ One bronchus (singular term) enters each lung, which is surrounded by a pleural membrane (thin flexible sac) The left lung has two lobes, and the right lung has three lobes. Part Function Structure 6- Human One goes to each Respiratory lung. System Full cartilage rings for Bronchus Each carries air into support (plural: lungs and splits into bronchi) many bronchioles 7- Many branches carry air Many branched tubes, Bronchio to alveoli smallest passageways, to le increase surface area Able to change diameter Smooth muscle walls to regulate air flow NO cartilage rings 8- Site of external Single cell layer, and the Alveoli respiration (gas one side is surrounded by (singular exchange). many capillaries. : ~500 million alveoli per Coated with “surfactant” alveolus lung! (a lipoprotein) to prevent Diagram of Bronchi/Bronchioles  Nasal Cavity Path taken by air Upper Path taken by food Respiratory Pharynx Larynx Epiglottis Tract Esophagus Trachea Bronchi Bronchioles Lower Alveoli Respiratory Diaphragm Tract Diagram of  Human Respiratory System Part Function Structure Diaphrag Increases and Dome shaped, thin, m decreases volume of muscular chest cavity The Mechanics of Breathing Air does not just flow into and out of the lungs on its own The muscular diaphragm & the rib The brain acts as a muscles — control the air pressure inside the respiratory control lungs centre to coordinate breathing movements and  Diaphragm and Rib Muscles The diaphragm is a dome-shaped layer of muscle that separates the region of the lungs from the region of the stomach and liver The rib muscles, or intercostal muscles, are found between the ribs and along the inside surface of the rib cage.  Diaphragm and Rib Muscles With regular signals from the brain, the diaphragm and the intercostal muscles work together at the same time to move air into and out of the lungs - These 2 structures control the air pressure within the  Protection for Lungs - Pleural Membrane Function Surrounds lungs and ◻ The constant movement of lines chest cavity the lungs could cause Reduces friction problems due to the friction between lungs and on the delicate tissue if it were chest cavity not for the pleural membranes Structure 🞑 These are membranes that cover Filled with fluid that the lungs and line the thoracic reduces friction cavity between lungs and 🞑 It is filled with fluid which acts like chest cavity during Pleural Membrane