AllSystemsGo

that's the he said the one he's gone nopee we are t-minus 30 seconds initiate kisses Jake musculoskeletal system he was helpful system is go eral vestibular system this video is systems go cardiopulmonary cardio pulmonary systems go cardiovascular cardiovascular system ago all systems are go we are t-minus ten nine eight seven six five four three two one and liftoff we have liftoff ok let's go through pain is Garcia main engine start four three two one bill and liftoff liftoff of the space shuttle and it has cleared the tower hi welcome aboard the space shuttle Columbia and Space Lab life sciences one after ten years of flying space shuttle missions we're becoming accustomed to the strange things that can happen in place but it hasn't always been that way when we first went into space no one knew how the human body would react to spaceflight we wondered if we could survive in weightlessness and we wondered if we could work in space okay I'm up 30 years later we know that the answer to both of these questions is yes but in spite of our successes in space many questions about the effects of spaceflight on the human body remain unanswered during the flight of space lab life sciences one my colleagues and I will try to answer some of these questions the human body is much like the shuttle it is a very complex sophisticated piece of living machinery that relies on several subsystems to perform its mission where the shuttle has a propulsion system a life-support system a guidance system and so on our bodies have systems like the cardiovascular system the cardiopulmonary system the renal endocrine system a blood and immune systems the musculoskeletal system and the neuro vestibular system the shuttle systems communicate with each other to keep the spacecraft flying smoothly in a similar way our body systems also talk to each other to maintain what is called homeostasis or a stable internal environment all of our body systems are affected to some degree by spaceflight the most dramatic change occurs immediately after we become weightless on earth the pull of gravity normally pulls our body fluids in our feet legs and abdomen but when we enter space and become weightless the fluid and our bodies is no longer pulled down toward our feet instead it shifts up to our chest and head since eighty percent of our body is fluid that changes the way we look our faces get puffy and our legs get skinny we call this the bird legs of space after we're up here for a while we adapt somewhat to the fluid shift but our bodies remain in this altered state until we're back on earth the weightlessness affects our bodies in another way to its class space motion sickness it's much like being seasick on earth but luckily our bodies adapt to this new environment until it isn't really a problem after the first couple of days the fluid shift + space motion sickness are easily recognizable changes that take place in weightlessness but less obvious changes also occur right down to individual cells during the flight of SPS 40 spacelab life sciences 1 my fellow crew members and I will introduce you to the six major body systems will learn how they function on earth and how spaceflight may affect them our cardiovascular system is a network of over 96,000 kilometers of blood vessels and not to go more than twice a really earth these blood vessels include arteries which carry freshly oxygenated blood to all the tissues in our bodies and other vessels called veins which bring back waist Laden blood so the process can be repeated the driving force of the cardiovascular system is the heart it's a pump that forces blood through the arteries and the veins our heart pumps are beat about 60 times a minute every minute of our lives if you live to be 70 years old your heart will pump more than tues billion times our cardiovascular system works well in gravity whether we're lying or standing we always have an adequate supply of blood for vital organs like the brain but when we go into space and take our hearts out of their normal environment some strange things happen the upward shift is fluid in our body tricks the heart and its sensors into believing that there's an increased blood supply so our heart tries to compensate first the muscle structure of our heart stretches so that it can hold more blood when this happens other body systems tell our kidneys to eliminate what appears to be excess fluid as the fluid level is reduced we believe our bone marrow shops on its production of red blood cells in order to keep our blood from getting too thick pretty soon the amount of blood and the red cells in our body is less than we have on earth with less blood to pump our heart shrinks back to about the same size it is on earth but when we return to Earth from space gravity again pulls much of our blood back to our legs now there's not enough blood to go around and some of us will get lightheaded and dizzy for a short time until our bodies get more fluids and manufacture more blood in spite of this there's no indication that space flight causes any permanent problems for our cardiovascular system but during this slide we're going to investigate this matter more closely before we departed earth I had a long plastic tube inserted into a vein in my arm this tube is called a catheter the tube was advanced in a vain to a point just above my heart during the first few hours of flight when the fluid shifts occur we're able to measure the central venous pressure near my heart sister venous pressure is directly related to the volume of blood our heart pumps once we get back to earth will do the same experiment see it's the central venous pressure measurements differ if our suspicions are correct will demonstrate the fluid shift caused by weightlessness increases activity and changes the control mechanism to the heart and circulation information like this will help us with better understand the changes we go when we first enter weightlessness and it will give us insight into the possible effects of long-term weightlessness as well as diseases of earthbound patients [Music] the cardiovascular system works closely with another body system called the cardiopulmonary system cardio refers to the heart and pulmonary first is lungs this lung heart connection is right in the middle of the cardiovascular system but not literally there's what I mean the heart pumps blood through our arteries and veins the blood turn has an equally important job when the blood is on its way to our tissue in organs it is said to be oxygenated meaning that it is carrying oxygen to all of the cells in my body when blood is returning from the cells his oxygen depleted meaning that the oxygen has been used up and in its place whose carbon dioxide looking at a diagram with the cardiovascular system we see that it's a closed system if this is true then how does the blood get a fresh supply of oxygen to carry back to the cells that's where the lungs come in oxygen depleted blood is pumped from the heart to the lungs things alone is see large air bag full of thousands of tiny blood vessels call Kappler my friend here is going to help me show what happens when we take a breath of air when we breathe air which with oxygen enters alive now we've got two lungs for fresh air and oxygen and we have a network of small blood vessels filled with oxygen depleted blood now something quite fascinating hounds the oxygen in the lungs and the carbon dioxide in the blood are going to trade places through the thin membranes that line lungs this phenomenon is called gas exchange now the antler is oxygen is depleted and the blood is oxygenated okay now you can breathe thank you the blood that returns to the heart where it's pumped out to the body to nourish yourself and give them off if it returns back to the heart and then again to the rungs with the processes again repeated on earth where gravity tends to pull blood toward our feet the majority of the blood in the lung stays near the bottom and the air stays mostly in the top but in space where the fluid in our body shifts upwards it is felt that there will be a more even distribution of blood and air in the lungs that means that the lungs should function even more efficiently in space than they do on earth spacely's gas analyzer is going to help us determine if this is true by bleeding into the rebreather device we only have a mixture of traceable gases when we exhale the mixture the gas analyzer will identify each gas and determine the quantity it was absorbed by the bloodstream investigators back on earth will then be able to determine if gas exchange Mullins is actually more efficient in space if that is the case it may help us to better understand certain respiratory problems that people have back on earth [Music] Sarah health a young person weighing about 120 pounds over sixty percent and certainly series hands of your body is made out of work that means that water is the most abundant and the most important fluid in your body but how do we keep our body water at a constant level every time we respired go to the bathroom we hear that body some water and every time we take a drink of water we add water back so how does the body speak the water can balance this is done for us automatically by our renal intercom system renal refers to the kidneys and the endocrine system is a collection of hormone secreting glands that include the hypothalamus the pituitary the thyroid gland the pancreas and the adrenal gland the primary bodied compounds regulated by this system are water and electrolytes when we drink water or other fluids they go into our gastrointestinal tract from their water and electrolytes are absorbed into the bloodstream by a process called osmosis the cells in our bodies then absorb whatever water they need from the bloodstream the cells also dumped water along failure waste into the bloodstream as the blood passes through our engine system it is monitored for different metabolic products two of the endocrine glands the hypothalamus and the pituitary monitor fluid levels in the blood if the fluid level is not right they will release the hormone and that Parma tells the brain there's a problem if the flood level is too low the brain tells us that reserves but if the fluid level of high the brain tells the kidneys to eliminate fluid through an elaborate filtering process our kidneys remove the excess tumors and waste from our blood and store it in our bladder in the form of urine when our kidneys or cobra body to get rid of water we make more urine in the body our bladders bill who would get the urge to urinate but walking father's clean for the space traveler for one it means that when we enter witnesses the body fluids shift upwards and our renal intercom system will tell our bodies to eliminate to it what we don't know is how weightlessness affects the production of hormones that keep our fluid levels found here on sls 14 investigating all the changes that occur during spaceflight changes in hormone production changes and how the kidney function on the circulation and with this new knowledge we hope to shed new light on things like how why would be conditioned here with this life and on earth trouble orthostatic hypertension and heart failure all of us know that blood is essential for life but do we really know why what has two very important jobs first it transports oxygen and carbon dioxide to and from the millions of cells in our bodies what is also a defense mechanism that allows our bodies to fight infection and disease blood has three components red blood cells which do the transporting of oxygen and carbon dioxide white blood cells which five infections and a watery fluid called plasma which makes our blood liquid and allows it to flow through the blood vessels let's take a look at each of these components a little closer red blood cells could be compared to millions of taxicab looming around in our body as each red blood cell taxes passes through our line it's wired down by an oxygen molecule the oxygen is wanting to go to one of the millions of cells that mix up our bodies so the red blood cell takes off the cardiovascular system toward that destination once they are the oxygen gets out and goes to the cell now like any good taxi driver the red blood cell doesn't want to make a return trip without a paying customer month so while it'll sell he picks up a carbon dioxide passenger for the return trip to the lungs without red blood cells ourselves can't get the oxygen they need to sustain life white blood cells also perform an important function they are a major part of our immune system from time to time foreign substances in our bodies these substances might be bacteria viruses or even something like a splinter who might compare the white blood cells to a good watchdog in our yard when someone or something forms that conventional cars are watched on the attack the white blood cells looks the same way except there are millions of them when a foreign substance enters our body the white blood cells attack and repel the intruder there are several types of white blood cells if the ones that were interested in on this flight are called loose excite the red and white blood cells would have a difficult time making it through our blood vessels if it works for our liquid called plasma in the red fluid we call blood cells make up about forty to forty-five percent the rest is classic this glass is a fluid it is really affected by the upward fluid shift that takes place in our body and we first encounter weight with you and then affects our body's overall blood supply here's how when the fluid in our bodies drifts upward sensors in the circulatory system and the endocrine system and a message to the brain saying that there's too much fluid the brain then tells the kidneys to reduce the fluid volume this is probably accomplished mainly through urination once the fluid level has been reduced blood cells make up more than forty-five percent of the blush reply in other words our blood becomes thicker to compensate Siddhant we think the bone marrow decreases its production of red blood cells until the racial returns to about 45 a shame so once again our bodies adapt to the changes of spaceflight but when we return to Earth we faced another problem we find that we've lost both blood volume and red blood cells the loss of blood volume is a problem immediately upon returning to earth because earth gravity is again pooling blood in our legs the decrease volume makes it more difficult for blood to be poked to our brain this can lead to lightheadedness and a woozy feeling right after landing we begin working to correct this problem even before we land by drinking lots of water by drinking water we begin to replace the plasma in our black but once the plasma level is increased he thinks another problem now we have fewer red blood cells from this shoot this condition is called space Amelia even though it doesn't actually happen until we're back on earth thanks anemia will continue until the body manufacturers enough red blood cells to bring the plasma cell ratio back to about forty five percent during the SLS one mission were setting several ways in which spaceflight may affect the blood and immune system for example in the past we have found the astronauts have fewer lymphocytes after flying in space and malicious sites that you have so not as effective in fighting insistence as they had been prior to stay flies at various times throughout this mission we're going to draw blood from the crew these specimens will be studied later on earth to determine if the lymphocytes ability to respond to infection decreases the longer they remain weightless this is an important question to be answered is that a functioning immune system our bodies would become easy prey for disease most structures are designed with a specific purpose in mind the orbiter was designed to function in the unique conditions of space our bodies were designed to function on earth where there's gravity in fact our bodies musculoskeletal system needs gravity to function properly balla body systems were studying during sls 1 the musculoskeletal system may be the only one that has serious problem adapting to the changes it encountered during spaceflight by pulling against our bodies gravity makes our bones and muscles work and become stronger each time we take a step and push our weight forward we perform a weight lifting exercise for the muscles in our legs activities like climbing stairs make our muscles work even harder but in space nothing has weight so our muscles don't have to work the same as they do on earth when muscles don't work in their usual way they become weaker most of us have known someone who's broken an arm or a leg and had to wear a cast while the bone heals while in the cast the muscles of that arm or leg didn't have to work and once the cast was removed the muscle was weak and had lost its bulk the same is true for people who have been confined to a bed for a long time and could not use their muscles in space we work our muscles on treadmills and exercise bikes but the results still aren't the same as they are on earth imagine that every day we lift the barbell that weighs 100 pounds then one day we go on a trip it lasts a month and you only have a 40 pound barbell to take with it even though we lift the 40 pound barbell every day the 100 pound barbell is going to be hard to lift when we return from our trip same is true about spaceflight even though we exercise in space we're going to be weaker when we return depending on how long we've been in space it may take us weeks or even months to regain the strength and our muscles that we've lost it could be even worse for astronauts will someday live on the space station or at lunar bases not to mention a trip to Mars that could last a year or more muscles aren't the only parts of our bodies which suffered during spaceflight weightlessness also causes our bones to lose the minerals calcium and phosphorus many of us don't think of our bones as being alive but they are really very active in our bone are two types of cells osteoclasts which get rid of old bone matter and osteoblasts which build new bone because of the activity of these two types of cells our bones are in a constant state of tearing down and rebuilding the balance of these cells seems to be tipped slightly in the favor of the osteoblast cells that's why our bones grow stronger but what happens in space is still somewhat of a mystery since there is no weight to bear in space then there is no stress on our bones as they go through the rebuilding process this seems to affect the structural integrity of our bones bone density recovers but without stress they may not grow as strong the only way to prove this theory is to test some of our bones for strength and the only way to do that is to remove the bone and so far we've had no volunteers so NASA is working on ways to study bone strength without removing the bone finding a way to test bone strength is going to help us to treat elderly patients who have a common bone problem known as osteoporosis here on sls one we're going to measure the level of calcium producing hormones and compare them directly to the uptake and release of calcium in the body it will be the first time that this has been done in the weightlessness of space [Music] it's a spectacular view out the window but most of the time looking outside doesn't tell us before flying the way we should since there aren't a lot of visual references in space the shuttle has a guidance system that helps keep us in the proper position we have a guidance system in our bodies too it's called the neuro vestibular system and it's what keeps our bodies in the proper orientation on earth the neuro vestibular system is very sensitive to gravity in fact it's gravity that makes it work deep inside our inner ear in the vestibular organ our thousands of tiny hairs resting on top of these hairs are microscopic clumps of crystals called odorless on earth gravity pulls the odorless in different directions according to the type of activity we're doing this in turn Ben's a tiny hairs sending messages that tell the brain if we're hanging upside down accelerating or any other sensation that has to do with body movement the neuro vestibular system also uses sensors in our muscle to determine sensations of motion or changes in position but most of all it relies on RI we might even say that the neuro vestibular systems main purpose is to create a stable platform for our eyes when our eyes can't lock on to what we're looking at we can get a queasy feeling we call motion sickness it's the same feeling some people get when they ride a wild ride at an amusement park everything rushes by in a blur and before long they think they might get a second look at the hotdog they just ate some of us who fly in space get a similar feeling we call it space motion sickness that doesn't mean riding the shuttle is like climbing aboard of tilt the wheel at a carnival but it does mean that space flight can confuse our neuro vestibular system and disorient the visual references we rely on for stability there's a reason for this when we get into space gravity no longer pulls down on us the way we're used to on earth things start to float away and for all practical purposes objects become weightless in this environment the vestibular system functions differently and it does on earth and we no longer have a way to tell our brain what the right body position is without the vestibular system functioning the way we're used to some of us get confusing signals in our brain our eyes tell us that our feet are off the ground but our vestibular organ doesn't give us the sensation of falling that we expect usually after a few days in flight our bodies adjust to the weightlessness and the space motion sickness goes away [Music] not everyone experiences space motion sickness and that's one of the medical mysteries would like to know more about the reason is quite obvious imagine getting off a ride at a carnival and someone hands you an algebra book and tells you to work a few problems that's what it's like playing astronaut is suffering from space motion sickness it's rather difficult to concentrate on an experiment if all you can think about is how sick you feel we want to have as much productive time as possible when we're in space so to help us learn more about the effect of space motion sickness and how to treat it we're going to do some experiments here on sls one one of my favorite experiment involves dislocating dome what the dome does is to help us see how visual cues affect the way our body responds to do the experiment Millie will put her head in the dome and look at the doxies they locate our eyes naturally want to lock onto the dot which causes her body to want to keep up with her eye and pretty soon her whole body will feel like it is turning but it really isn't a camera mounted in the dome is recording for I reaction backorder scientists will study this and other data we've collected you see if they can answer some of the questions about how our neural vestibular system work and why we get safes motion clicking I'll leave you with a small bit of a bike the next time you're on a roller coaster ride and you feel yourself getting sick just close your eyes our body systems are so different from each other yet they all depend so much on each other they perform their jobs each day in a way that most of us never realize our garlic NASA is to enable the human exploration of faith but to do that we have to understand how space affects our bodies safe lab mission like this one are a step toward that goal but only a small step orbiting laboratory will allow us even longer periods to investigate the mysteries of the human body hopefully the benefits of all safe space research may someday help solve the puzzles of such of earthbound problems as heart disease emphysema osteoporosis and other disorders the possibilities are as limitless as the stars themselves late life sciences one has been a valuable learning experience for all of us we're really glad you could join us on this voyage of medical discovery [Music] [Applause] [Music] you [Music]