2Respiratory System Purpose: To transports O2 and CO2 from atmosphere to the cellsTwo typesExternal: use lungs to exchange gases from the air to our bloodInternal: to exchange gases between our blood and our cells
3Respiratory system is located in the thoracic cavity. Lies above the diaphragmThe diaphragm is a largesheet-like muscle thatdivides the thoracic andabdominal cavities.
4Respiratory System1. As you breathe in the air should enter via your nostrils/nares.Nasal hairs filter airNasal chambers moistens and warms the air.
52. Air then passes through the pharynx Back of throat area/behind uvulaA common passage for food & air3. The pharynx directs air into the larynx.-Larynx is referred to as the Adam’s Apple or Voice Box-Inside the larynx is the vocal cords-As air passes through the vocal cords these thin bands of tissue vibrate allowing you to make sounds.
6When you swallow this flap closes making a slight sound. 4. The larynx has a flap of tissue protecting its opening called the epiglottis.When you swallow this flap closes making a slight sound.Purpose of the epiglottis is to prevent food from entering and blocking the respiratory pathway.
75.From the larynx the air passes into the trachea. Known as the windpipeApproximately 4 ½ inches longProtected by rings of cartilagethat prevents it from collapsing asair moves in and out.
86. The trachea branches to make two smaller tubes called bronchi Bronchi direct the air into the lungsBronchi divide into smaller branches called bronchioles.Bronchioles keep dividingup to 20 times and eventuallybecoming the air ducts.
9-Bronchioles, bronchi and trachea are all lined with small hair like structures called cilia. Cilia trap foreign particles and push them back towards the throat area.-Air ducts empty into our air sacs or alveoli.
107. -Alveoli is where our gases are exchanged -Average human has 300,000,000 alveoli.
12The lungs are surrounded by a double membrane known as the pleura. Keeps the lungs pressurized so air can move in and out.Secretes a slippery fluid which reduces friction
13Mammal lungs are made up of several lobes. 3 lobes on right side2 lobes on left side
14Inspiration: Expiration: Air moves into the lungs from the atmosphere. Air we breathe is 21% oxygen and .03% carbon dioxideExpiration:Air moves out of the lungs into the atmosphereAir we exhale is 14% oxygen and 5.6% carbon dioxide.
16Inspiration/Inhaling: Air moves into lungsChest expandsRibcage moves up andout / expands spaceDiaphragm flattens and pushesdownAbdominal muscles relax.Increase volume of thoracic cavityPressure inside the cavity is lower than outside the cavityAir moves from high to low causing air to move into the lungs.
17Expiration/Exhaling: Air moves out of lungs-Chest decreases in size-Ribcage relaxes and moves in-Diaphragm moves up into aconcaved shape.-Abdominal muscles contract.Decrease volume of thoracic cavityPressure inside the cavity is higher than outside the cavityAir moves from high to low causing air to move out the lungs.