Could humans ever breathe underwater? By Marta Bakowska-­‐Mathews Introduction *  History of scuba diving *  Boyle’s Law *  How fish, whales and humans breathe underwater *  Whether or not we will ever be able to breathe underwater *  DNA linking *  Harrison Okene Marta Bakowska-­‐Mathews Could humans ever breathe underwater? History *  Hold ones breath and resist from diving very deep *  Snorkel *  Diving bells *  Scuba system – tanks with helium and oxygen/regulators/pressure gauges http://upload.wikimedia.org/
wikipedia/commons/a/af/
Diving_bell.jpg Marta Bakowska-­‐Mathews Could humans ever breathe underwater? (1) Gas supply chamber (2) On/Off Valve (3) First-­‐Stage Regulator (4) Second-­‐Stage Regulator (5) Pressure Gauge http://www.bishopmuseum.org/research/treks/
palautz97/oc.gif Marta Bakowska-­‐Mathews Could humans ever breathe underwater? Boyle’s Law and Scuba Diving *  PV=c (P=pressure V=volume c=constant) *  As diver descends, water pressure ↑ therefore volume of air has to ↓ *  This happens in the tank and body *  E.g. you have to pop your ears when descending *  E.g. have to release excess air from buoyancy compensator on ascent because air in it is expanding. Marta Bakowska-­‐Mathews Could humans ever breathe underwater? Rules *  Don’t hold your breath underwater Lungs may stretch because air expands *  Ascend slowly Nitrogen gas is absorbed on descent It expands on ascent which may cause air bubbles in blood and decompression sickness Marta Bakowska-­‐Mathews Could humans ever breathe underwater? How fish breathe underwater *  Water enters the mouth *  Mouth and throat force water over gills *  Water has higher concentration of oxygen than blood *  Therefore, dissolved oxygen enters blood through blood vessels *  CO2 is expelled Marta Bakowska-­‐Mathews Could humans ever breathe underwater? Fish Marta Bakowska-­‐Mathews Could humans ever breathe underwater? http://reptools.rutgers.edu/Functpage34.html How whales breathe underwater *  Whales absorb 90% of oxygen in one breath (15%-­‐
human) *  Stores excess in myoglobin (muscles) *  Have higher levels of myoglobin than average animal *  When they dive, heart beats slower and certain arteries constrict (slows flow of blood without ↓ blood pressure -­‐ Bernoulli's principle) Marta Bakowska-­‐Mathews Could humans ever breathe underwater? How do humans breathe *  Diaphragm expands (↓ pressure in chest cavity) *  Air flows in and inflates lungs (high to low P) *  Exhaling makes the chest cavity smaller (↑ pressure – Boyle’s Law) *  Air from the lungs leaves body (high to low P) Marta Bakowska-­‐Mathews Could humans ever breathe underwater? * Alveolar sacs are connected to bronchioles by tiny ducts * Capillary beds (blood vessels) that surround sacs, allow oxygen molecules to pass to red blood cells through thin balloon-­‐like walls * CO2 molecules go the other way Marta Bakowska-­‐Mathews Could humans ever breathe underwater? (a)  Nasal cavity (b) Pharynx (c)  Larynx (d)  Trachea (e)  Alveoli (f)  Bronchial Tree (g)  Diaphragm Marta Bakowska-­‐Mathews Could humans ever breathe underwater? How to be able to hold your breath longer *  Breathe deeply *  Learn to keep your heart rate low (splash cold water on your face) *  Relax your muscles *  Do breathing exercises (balloons, hyperventilating, hold breath) *  Exercise in water/at high elevation *  Play a wind instrument Marta Bakowska-­‐Mathews Could humans ever breathe underwater? Breathing underwater *  You need gills to extract oxygen from water *  Our lungs don’t have enough surface area *  We are warm blooded animals so we need more oxygen to heat up *  We don’t have the force to get water out of our lungs Marta Bakowska-­‐Mathews Could humans ever breathe underwater? http://wps.prenhall.com/
esm_audesirk_bloe_7/17/4460/1142010.cw/
index.html. Breathing vs. holding your breath *  We want to breathe and not just hold our breathe *  World record is 22 min *  Have to use as little energy as possible to do this *  Takes a lot of training *  Not too helpful to general society http://www.huffingtonpost.com/2012/11/16/
breath-­‐world-­‐record-­‐stig-­‐
severinsen_n_2144734.html DNA linking *  Bioengineers stated that human and marine algae DNA can be linked *  Salamanders and algae in symbiosis *  Successful symbiosis is possible between plants and vertebrates Marta Bakowska-­‐Mathews Could humans ever breathe underwater? Conclusion *  Fish survive underwater differently to humans and whales *  Boyle’s law is what really helped advance scuba diving *  Humans will only be able to breathe underwater if we change anatomically *  Just like the advancement of scuba diving, breathing underwater may one day happen Marta Bakowska-­‐Mathews Could humans ever breathe underwater? Harrison Okene *  Was part of a shipwreck *  Was stuck in an air bubble (diving bell) for 60hr *  Humans need 10 cubic m of air per day *  1atm of pressure is added for every 10m *  He only needed 6 cubic m *  His chamber was only 4 feet high *  Air could only diffuse one molecule at a time which would take ages Marta Bakowska-­‐Mathews Could humans ever breathe underwater? References *  http://www.interestingtopics.net/humans-­‐will-­‐breathe-­‐under-­‐water-­‐
id-­‐628 *  http://www.air-­‐n-­‐water.com/breathing-­‐underwater.htm *  http://physics.itsbaxter.com/pressure.html *  http://scuba.about.com/od/Theory/p/Boyles-­‐Law-­‐And-­‐Scuba-­‐
Diving.htm *  http://scuba.about.com/od/Theory/p/Boyles-­‐Law-­‐And-­‐Scuba-­‐
Diving.htm *  http://www.slate.com/articles/health_and_science/science/2013/06/
harrison_okene_s_shipwreck_air_bubble_how_could_he_survive_u
nderwater_for.html *  http://chickscope.beckman.uiuc.edu/explore/embryology/day15/
focuson_humans.html Marta Bakowska-­‐Mathews Could humans ever breathe underwater?