Gas exchange

Alternative transcript:

surface area. the 3D sacks and so have a large surface area efficient diffusion + respiration. H INTERCOSTAL MUSCLES EXHALING →→ Diaphragm relaxes (becomes domed) intercostal muscles relax. - ribs move down and in. → decreases volume → inside → increases pressure. INHALING intercostal muscles contract. - ribs move up + out. → the diaphragm contracts and flattens. →Decrease pressure increases volume. air will go rushing out (away from high pressure). chest cavity. SMOKING TAR Sticky substance that coats teeth + gums. damages enamel, causing teeth to decays. damages nerve endings, causing loss of smell. NICOTINE addictive → narrows blood vessels, damages lining cells come to fix them then. blood pressure higher. → makes red blood cells stickier, causing more blood clots. EFFECT ON AIR PASSAGES G triggers dopamine + endorphins. make it thicker, making paralyses cilia in air ways. → they can no longer waft, so there is a build up of mucus. causes disease and lung infections. CARBON MONOXIDE → combines irreversibly with haemoglobin in red blood cells. - displaces oxygen which cannot provide for respiration, Causing fatigue + Shortness of breath. → linked to neart disease → effects fetuses as well. EMPHYSEMA →shortness of breath, coughing, wheezing. → coats + damages the alveoli, leads to them rupturing. decreases surface area for gas exchange. 1 H: FUNCTIONS OF GAS EXCHANGE INTERCOSTAL MUSCLES → muscles betwleen ribs. → help move the rib cage up and down. TRACHEA → Windpipe going down your throat. → made of smooth muscle and cartilage rings, nice and strong and flexible. - They have ciliated epithilial cells in the lining to waft mucus. BROWCHI carries air from trachea to Bronchioles. same muscle and cartilage as Trached. also have aliated epithilial cells. BROWCHIOLES → 3 carry air from Bronchi to alveoli. RIBS →The bone structure that protects heart and lungs. → keep structure of thorax. DIAPHRAGM sheet of muscle that sits below ribs + lungs. → domed when relaxed and flat when contracted. 7 → it relaxes or contracts to create or release pressure and volume in the lungs, so they can bring air in and push it out. PLEURAL MEMBRANES → bag that holds lungs. →in chest cavity. ALVEOLI air sacks that are connected to the bronchioles. thousands of them in lungs. 'where gas exchange takes place. D! L BREATHING RATE EXPERIMENT INDERENDENT VARIABLE → the thing that you change → exercise / no exercise. type of activity. DEPENDENT VARIABLE → what you measure. Breathing rate / breaths per minute. CONTROL VARIABLE → things you keep the same. → level of less age of person → food and water intake. REPEAT →DO a few times for relicubility and average. MEASURE → time taken for experiment. → Exercise for 1 minute. →Breaths per min. 1