Respiratory System

RESPIRATION 3 levels External: External: –Moving gases from outside environment into lungs and back. – Breathing. Internal: Internal: –Moving O2 from lungs through bloodstream to mitochondrion of tissue cells and CO2 back. Chemical: Chemical: –Aerobic respiration within the mitochondrion. –C6H12O6 + 6O CO2 + 6H2O + "e" –ADP + P + "e" ATP

Control of Breathing You breath to get O2 to Mitochondrion of cells to carry out the breakdown of glucose. You breath to get O2 to Mitochondrion of cells to carry out the breakdown of glucose. C 6 H 12 O 6 + 6O CO 2 + 6H 2 O + "e" C 6 H 12 O 6 + 6O CO 2 + 6H 2 O + "e" 6 O 2 's in equals 6 CO 2 's out 6 O 2 's in equals 6 CO 2 's out The control of breathing is maintaining a delicate balance (Homeostasis) between the concentrations (pressures) of these two gasses in your blood. The control of breathing is maintaining a delicate balance (Homeostasis) between the concentrations (pressures) of these two gasses in your blood.

Respiration / Breathing Control Center Located in Medulla /Pons of brain. Located in Medulla /Pons of brain. Coordinates with sensors in spinal cord, rib muscles and lungs. Coordinates with sensors in spinal cord, rib muscles and lungs. Monitors pH of blood and signals rib muscles and diaphragm to contract / relax. Monitors pH of blood and signals rib muscles and diaphragm to contract / relax.

Place in order O 2 would follow. Trachea Trachea Body Cells Body Cells Pharynx Pharynx Sinuses Sinuses Bronchi Bronchi Bronchioles Bronchioles Larynx Larynx Nasal Pharynx Nasal Pharynx Alveoli Alveoli Bronchiole Tubes Bronchiole Tubes Blood Capillaries Blood Capillaries Red Blood Cells Red Blood Cells Glottis Glottis Mitochondria Mitochondria Nasal Openings Nasal Openings Hemoglobin Hemoglobin

BREATHING Respiration Center in Medulla sends impulse to intercostals and diaphragm to contract (14 / min) Respiration Center in Medulla sends impulse to intercostals and diaphragm to contract (14 / min) Air is drawn into lungs and due to pressure and concentration differences O2 & CO2 diffuse into and out of blood capillaries through alveoli. Air is drawn into lungs and due to pressure and concentration differences O2 & CO2 diffuse into and out of blood capillaries through alveoli.

Breathing (2) Stretch sensors in lungs and pH sensors in brain and spinal cord react and control breathing center impulses. (Feedback systems) Stretch sensors in lungs and pH sensors in brain and spinal cord react and control breathing center impulses. (Feedback systems) –if stretch sensors detect overfilling - suppress impulses until overridden by pH sensors. –pH sensors monitor build-up of carbonic acid---as pH goes down in blood Pons / Medulla increase impulse rate and visa versa

Breathing (3) O2 level has little to do with the rate as monitors deal primarily with CO2 levels....remember 6O2's in = 6CO2's out O2 level has little to do with the rate as monitors deal primarily with CO2 levels....remember 6O2's in = 6CO2's out Can consciously override the system but only temporarily....I'm going to hold my breath until I die!!!!!! Can consciously override the system but only temporarily....I'm going to hold my breath until I die!!!!!!

STEPS IN RESPIRATION Medulla sends signal out to rib muscles and diaphragm. Medulla sends signal out to rib muscles and diaphragm. Rib muscles and diaphragm contract (ribs move upwards and outwards and diaphragm moves downwards) expanding the chest cavity. Rib muscles and diaphragm contract (ribs move upwards and outwards and diaphragm moves downwards) expanding the chest cavity. A negative pressure or vacuum is created causing outside air to be drawn inwards by BULK FLOW. A negative pressure or vacuum is created causing outside air to be drawn inwards by BULK FLOW.

STEPS IN RESPIRATION (2) Air moves in through nose, sinuses, nasal pharynx, past epiglottis and through glottis, down trachea, bronchi, bronchioles and into alveoli of lungs. Air moves in through nose, sinuses, nasal pharynx, past epiglottis and through glottis, down trachea, bronchi, bronchioles and into alveoli of lungs. Oxygen DIFFUSES from alveoli into blood capillaries and into red blood cells where it is picked up and carried by hemoglobin. Oxygen DIFFUSES from alveoli into blood capillaries and into red blood cells where it is picked up and carried by hemoglobin. Oxygen moves by BULK FLOW throughout blood circulation to cells where concentrations are lower Oxygen moves by BULK FLOW throughout blood circulation to cells where concentrations are lower

STEPS IN RESPIRATION (3) Oxygen DIFFUSES out of hemoglobin in red blood cells and into cells and finally to mitochondria. Oxygen DIFFUSES out of hemoglobin in red blood cells and into cells and finally to mitochondria. Cellular respiration occurs and oxygen in consumed and carbon dioxide is generated as a waste gas. Cellular respiration occurs and oxygen in consumed and carbon dioxide is generated as a waste gas. Carbon dioxide DIFFUSES out of cells and into blood capillaries where it moves through red blood cells and is converted to bicarbonate ions and carried in the blood serum as carbonic acid. Carbon dioxide DIFFUSES out of cells and into blood capillaries where it moves through red blood cells and is converted to bicarbonate ions and carried in the blood serum as carbonic acid.

STEPS IN RESPIRATION (4) Carbonic acid moves by BULK FLOW throughout blood circulation and back to lung capillaries. Carbonic acid moves by BULK FLOW throughout blood circulation and back to lung capillaries. Carbonic acid moves through red blood cells, is converted back to carbon dioxide and DIFFUSES into alveoli of lungs. Carbonic acid moves through red blood cells, is converted back to carbon dioxide and DIFFUSES into alveoli of lungs. Medulla signals rib muscles and diaphragm to relax, (ribs move down and inwards and diaphragm moves upwards) causing a positive pressure in chest cavity. Medulla signals rib muscles and diaphragm to relax, (ribs move down and inwards and diaphragm moves upwards) causing a positive pressure in chest cavity.

STEPS IN RESPIRATION (5) Air is forced back out of the system by BULK FLOW. Air is forced back out of the system by BULK FLOW. Air moves out of alveoli of lungs, through bronchioles, bronchi, and trachea, through glottis and past epiglottis, up through nasal pharynx, sinuses and out through the nose. Air moves out of alveoli of lungs, through bronchioles, bronchi, and trachea, through glottis and past epiglottis, up through nasal pharynx, sinuses and out through the nose.

Blood Carriers of Gas O 2 diffuses from lungs into blood capillaries to RBC and is picked up by iron atom in Hemoglobin molecule. O 2 diffuses from lungs into blood capillaries to RBC and is picked up by iron atom in Hemoglobin molecule. CO 2 diffuses out of Mitochondrian of cells, into capillaries and through RBC CO 2 diffuses out of Mitochondrian of cells, into capillaries and through RBC –in RBC CO 2 + H H 2 CO 3 (carbonic acid) –Hemo causes change of H2CO3 to HCO 3 + H+ ions (bicarbonate) –Bicarbonate diffuses out of RBC and into blood serum –H+ ions carried by Hemoglobin –* In lungs reaction is reversed –HCO 3 + H -  H 2 CO 3 -  H 2 O + CO 2 –CO 2 diffuses out of blood into alveoli