1 12 mechanisms of breathingPresentation Transcript
Do NowDescribe the journey of air through the respiratorysystem using the following words: Larynx Pharynx Trachea Nose Alveoli Bronchi Bronchioles
Do Now1. Nose2. Pharynx3. Larynx4. Trachea5. Bronchi6. Bronchioles7. Alveoli
Objective: What mechanisms are involved in breathing?
Gas Exchange Oxygen and carbon dioxide move across walls of capillaries and alveoli (why?)1. Oxygen dissolves from the alveoli into blood through capillary walls2. CO2 dissolves from the blood into alveoli through capillary walls
What process allows oxygen/CO2 to move in the directions they do? Diffusion!Remember: molecules move from high to low concentration1. Oxygen concentration is greater in the air so it moves to caps2. CO2 concentration is greater in the blood so it moves to alveoliDraw it!Let’s look at2 alveoli
Regents Review Diagrams A and B represent structures found in the human body. Diagram B represents the functional unit of which structure represented in diagram A?1. structure 12. structure 23. structure 34. structure 4
Transporting oxygen Hemoglobin (remind us, someone!)1. Protein that binds oxygen after it diffuses into caps2. Transports oxygen in blood3. Remember, in red blood cells
How do we breathe?We don’t suck the air in!By moving our diaphragm we change air pressure inour chest allowing air to move in and out The diaphragm is a muscle in the body under the lungs that allows for inhaling and exhaling
InhalationDiaphragm contracts and flattensThis creates a vacuum using air pressure Pressure in the lungs is lower than the outside so air rushes in (remind you of a process?) This is a form of diffusion!
Exhalation Exhalation is a passive process – requires no energy Diaphragm relaxes and air pressure pushes the air back out of the lungsNote: these processes onlywork if chest cavity is sealed- If punctured, air pressureleaks out and can’t inhale orexhale
Regents Review Which row in the chart below correctly shows what systems A, B, and C provide for the human body? Row System A System B System C1. blood cells glucose hormones2. oxygen absorption gametes3. gas exchange nutrients waste removal4. immunity coordination carbon dioxide
Inhale vs. Exhale
Breathing and HomeostasisBreathing is initiated by the brain in the medulla (Evidence? /)Don’t have to think about breathing – you do it subconsciouslyBrain monitors CO2 level Breathing increases as CO2 level increasesYou can control your breathing if needed – thinkof when you play an instrument!
Smoking and the Respiratory System Dangerous Chemicals - some chemicals can bypass cilia and mucus and cause damage Chemicals in tobacco smoke damage structures in the system Dangerous chemicals:1. Nicotine – addictive; increases blood pressure and heart rate Constricts blood vessels in circulatory system2. Carbon monoxide – blocks oxygen binding to hemoglobin3. Tar – 60% of compounds cause cancer
Other problems with smokingTobacco smoke paralyzes cilia – (predict problems)Can’t push particles up – develop “smoker’s cough”Swelling of respiratory tract Reduces airflow
Diseases caused by smoking1. Chronic bronchitis Bronchi get inflamed and filled with mucus2. Emphysema Loss of elasticity and breakdown of lung tissue Cannot get oxygen into alveoli and in blood3. Lung cancer 87% of lung cancer comes from smoking Second hand smoke increase rate of disease of others in circulatory and respiratory system, too – especially kids.
Regents Review Smoking may damage the respiratory system because deposits from the smoke can1. interfere with ciliary action in the trachea2. trigger the release of antigens by the alveoli3. block the transmission of impulses that regulate breathing4. lower blood pressure in the mucous membranes of the bronchioles
Regents ReviewDeposits from cigarette smoke are most likely tointerfere with the ciliated mucous membraneslocated in both thetrachea and esophagusalveoli and livernasal cavity and tracheaepiglottis and esophagus
Regents Review The table below provides someinformation concerning organelles and organs. Based on this information, which statement accurately compares organelles to organs?1. Functions are carried out more efficiently by organs than by organelles.2. Organs maintain homeostasis while organelles do not.3. Organelles carry out functions similar to those of organs.4. Organelles function in multicellular organisms while organs function in single-celled organism