130 likes | 150 Views
food. O 2. ATP. CO 2. Why a respiratory system?. Need O 2 in for cellular respiration make ATP Need CO 2 out waste product. Passageways and Lungs. Respiratory system consists of a pair of lungs & a system of tubes that carry air to them
E N D
food O2 ATP CO2 Why a respiratory system? • Need O2 in • for cellular respiration • make ATP • Need CO2 out • waste product
Passageways and Lungs • Respiratory system consists of a pair of lungs & a system of tubes that carry air to them • Breathing is just one of the functions that the respiratory system carries out
The path air takes • Air enters through the nasal cavity • It passes through the pharynx and larynxinto the trachea
The path air takes • The trachea forks to form two bronchi • Each bronchus branches into numerous bronchioles • The bronchioles end in clusters of tiny sacs called alveoli- 1 cell layer thick wall
Lungs • Structure spongy texture • high surface area • more absorption of O2 • alveoli • small air sacs • moist lining • mucus traps dust, pollen, particles • covered by cilia • hair-like extensions of cells • move mucus upward to clear out lungs
Moving gases into bloodstream • Inhale • O2 passes from alveoli to blood • by diffusion • Exhale • CO2 passes from blood to alveoli • by diffusion capillaries (circulatory system)
O2 O2 O2 O2 CO2 CO2 CO2 CO2 Gas exchange: Diffusion of gases • Gases move by diffusion from high to low concentration • capillaries are thin-walled tubes of circulatory system • alveoli are thin-walled sacs of respiratory system capillaries in lungs capillaries in muscle External respiration: exchange of gases between alveoli and blood Internal respiration: exchange of gases between blood and cells blood lungs blood body
The Mechanics of Breathing • Breathing ventilates the lungs • The action of your diaphragm and the muscles between your ribs enable you to breathe in and breathe out • Breathing is the alternation of inhalation(active) and exhalation (passive)
Control of Respiration • Breathing is usually an involuntary process • Partially controlled by an internal feedback mechanism that involves signals being sent to the medulla oblongata about the chemistry of your blood • measure blood pH • CO2 = pH (acid)
Control of Respiration • coordinate breathing, heart rate & body’s need for energy • Will send nerve signals to the rib muscles and diaphragm • Nerve signals cause these muscles to contract, and you inhale
ATP CO2 O2 Breathing and Homeostasis • Homeostasis • keeping the internal environment of the body balanced • need to balance O2 in and CO2 out • need to balance energy (ATP) production
ATP CO2 O2 Breathing and Homeostasis • Exercise • breathe faster • need more ATP • bring in more O2 & remove more CO2 • Disease • poor lung or heart function = breathe faster • need to work harder to bring in O2 & remove CO2
Cleaning dirty air • To prevent foreign material from reaching the respiratory system is lined with ciliated (hair) cells that secrete mucus • The cilia constantly beat upward in the direction of your throat, where foreign material can be swallowed or expelled by coughing or sneezing