Presentation on theme: "Respiratory System. Function: exchange gases between blood (body) and the environment O 2 in CO 2 out Respiratory System."— Presentation transcript:
Function: exchange gases between blood (body) and the environment O 2 in CO 2 out Respiratory System
Airways Lungs Alveoli Components:
Nares (nostrils) Nasal cavity clean, warm, moisten air Pharynx (throat) clean, warm, moisten air Larynx: contains vocal cords Trachea: ciliated lining, cleans air Bronchi enter lungs Bronchioles (branches) Components of the Airway
Lungs: contain many alveoli (air sacs) very large surface area Alveoli: site of gas exchange between air and blood surrounded by capillaries oxygen enters the blood and carbon dioxide enters the alveoli through diffusion. Components:
How do we Breathe In? Diaphram contracts and moves down Rib cage moves up and out Size of the thoracic cavity increases Pressure in the lungs decreases Air rushes into the lungs from an area of high pressure to low pressure
How do we Breath Out? Diaphram relaxes and moves up Rib cage moves down and in Size of the thoracic cavity decreases Pressure in the lungs increases Air rushes out of the lungs from an area of high pressure to low pressure
What Controls Breathing Rate? Brain senses carbon dioxide levels in the blood If carbon dioxide levels increase, the brain signals the diaphragm to increase the rate of breathing.