1.Air enters through the external nares (nostrils) 2. Nasal cavity. Nasal cavity is lined with ciliated, mucosal epithelial tissue that trap inhaled particles and sweep them towards the throat to be swallowed and digested. Contains three lobes (conchae) which increase the surface area of mucosa exposed to air to better trap particles 3.Pharynx (upper throat) Passage for both food and air Contains tonsils The cilia in the nasal cavity don’t work as well in cold weather, which is why you may get a runny nose in the cold.
4.Larynx (aka voice box) Acts to prevent food and liquid from going into trachea. Epiglottis is located at the top of larynx. Normally it allows free passage of air, but when we swallow, the larynx is pulled up and the epiglottis tips over, sealing off the larynx. The vocal cords – a pair of membranes that vibrate as we expel air are also in the larynx. The passage between the vocal cords is the glottis. If food / liquid does get past the epiglottis, it triggers the cough reflex. Put your hand over your throat and swallow – what you feel moving is your larynx! Swallowing animation!
5.Trachea also contains ciliated mucosa to trap particles 6.Bronchi Largest air tubes of lungs 7.Bronchioles Smallest of the air tubes 8.Alveoli Site of gas exchange Take up most of the space of the lungs Covered with capillaries to exchange gasses with blood. Bronchitis = inflammation of bronchi
» Sinuses Spaces in the skull bones Act as resonance chambers for speech and produce mucus Sinusitis = inflammation of sinus membranes Pleural membranes Sac surrounding lungs Fluid-filled space reduces friction as lungs expand and contract Tightly bound to thorax wall, which is essential to breathing b/c it allows the lungs to expand and contract with muscular movement.
» What structures in the respiratory system help with disease prevention? Are those structures specific or non-specific defenses? » Name some similarities between the cardiovascular and respiratory systems.
» Inspiration Diaphragm & external intercostals contract, expanding the chest cavity and the lung capacity. Causes a decrease in pressure within the lungs. Air rushes into the lungs. » Expiration Diaphragm & external intercostals relax, reducing the chest cavity and the lung capacity. Causes a increase in pressure within the lungs. Air rushes into the lungs. Watch me! Exhalation is normally passive (we just relax muscles, we do not contract any), but we CAN actively exhale and do after exercise. How does the process of breathing help the cardiovascular system?
» Breathing rate is controlled by respiratory centers in the pons and medulla. » There is a ‘normal’ rate of inspiration (12 -15 breaths / min) maintained by self-exciting cells » Many sensory inputs act to increase or decrease this normal Low O 2 ↑ High CO 2 ↑ Low blood pH ↑ Irritants/stretch ↑ High body temp ↑ Emotions ↑↓ Volition ↑↓ Usually, Our body is more sensitive to CO 2 / blood pH levels than to O 2 Revisit Do Now – How is breathing regulation similar to and different from heart beat regulation?
Chronic Obstructive Pulmonary Disorder » 3 rd or 4 th leading cause of death (after heart disease and cancer, about tied with stroke) » Inability of air to get to capillaries of lungs » Two major diseases associated with COPD Chronic bronchitis – inflammation of bronchi & excessive mucus production Emphysema – destruction of alveoli COPD is strongly associated with smoking, but it can also be caused by air pollution How does each disease reduce gas exchange?
Shortness of breath Enlargement of right side of heart COPD is also characterized by high CO 2 levels – so high, that overtime, the body starts to ignore that information and focus on O 2 levels
Pulmonary rehabilitation breathing exercises Surgery removal of part of the lungs or lung transplant
1.What were our objectives and what did you learn? 2.How does this relate to our unit question? (How do body systems work together?) 3.How did we demonstrate our learner profile trait?