Agenda 2/2 and 2/5 Respiratory System Notes Lung Cancer and Emphysema project Homework: 1. WB Section #187, 188, 189, 190 2. Fix IA (hard deadline is Tuesday) Turn in: Video Notes

Overview of Respiratory System Lungs work with heart and blood vessels to ensure the body cells are properly supplied with oxygen, and that carbon dioxide is able to leave our body as waste Ventilation is the process of filling our lungs with air and then expelling that air Air sacs (alveoli) is where gas exchange occurs Oxygen diffuses into red blood cells, carbon dioxide diffuses out

Ventilation Lung tissue is not a muscle Muscles surrounding the lungs contract to allow you to breath Diaphragm, muscles in your abdomen, intercostal muscles (around ribs) Breathing is based on an inverse relationship between pressure and volume An increase in volume leads to a decrease in pressure A decrease in volume leads to a increase in pressure

Anatomy

Inspiration (Breathing In) 1. Diaphragm contracts, abdominal muscles raise rib cage Volume increases in thoracic cavity 2. Increase in volume causes a decrease in pressure 3. The lung tissue increases its volume since there is less pressure ‘pushing them down’ 4. Air comes in through your mouth or nasal passages and fills the lungs… the air fills the alveoli http://www.argosymedical.com/Muscular/samples/animations/Respiration/

Gas Exchange in Alveoli Path of air: Trachea right and left primary bronchi  smaller branches of bronchi  very small branches called bronchioles  air sacs (called alveoli) There are about 300 million alveoli in your lungs Each is surrounded by a capillary bed

Gas Exchange in Alveoli Blood brought to the lungs is low in oxygen and high in carbon dioxide When blood passes by alveoli, the oxygen will diffuse into the blood cell and carbon dioxide will diffuse out Concentration gradient ensures these molecules move the ‘right direction’

Cells in Alveoli Type 1 Pneumocytes: Very thin with a large surface area, making it the spot of diffusion Cannot be replaced by mitosis Type 2 Pneumocytes: Little surface area, produces a solution that acts as a surfactant Prevents the sides of the alveoli from sticking to each other Can be replaced by mitosis

Alveoli Diagrams

Sketch Diagram

Emphysema Disease where alveoli are slowly destroyed Leading cause is smoking Other known causes: marijuana smoke, fumes from manufacturing plants, coal dust, air pollution Known as COPD (chronic obstructive pulmonary disease) Turns alveoli into irregular shapes with holes, so gas exchange in less effective

Lung Cancer Cancerous growth that beings in the lungs Known to metastasize (spread) to brain, bones, liver, and adrenal glands Cancerous growth replaces healthy lung tissue Caused by carcinogens Carcinogens are substances that cause cells to mutation and turn into a cancerous cell Example: cigarette smoke

Lung Diseases Project You will create an artifact that summarizes information known about emphysema and lung cancer. You can decide what you will create, but it needs to include the following: Symptoms of both diseases Treatments of both diseases Prevalence throughout time (more common today, less common today?) An explanation for the change in prevalence over time Diagrams and pictures that compare healthy lung tissue to diseases A description of how the disease affects gas exchange The social consequences of these two diseases At least 6 academic sources