why do we have 2 kidneys, lungs and ovaries, but only one heart, liver and spleen?
478865
There are no definite answers, except that millions of years of evolution has deemed it necessary, but if you look at the organs function it can give you some clues.\n\nMost people know that that we breath in Oxygen and breath out Carbon Dioxide, but don't actually know why. Oxygen is essential to a process called "Cellular Respiration", but the short answer is that Oxygen is needed to bind to the waste products of our cells using sugar for food. When humans have to switch to fat for energy, like when your exercising, massive amounts of oxygen is needed to get rid of the waste products, so much so that two lungs can't even keep up. \n\nKidneys are the organs that regulate our bodies chemistry. Especially Ph levels that have to be in a very narrow range for our cells to stay alive. It's possible that a person could live with one of them, but by their nature, kidney's absorb poisons and damage themselves, and if you've only got one and it starts to have damage areas it would lead to death.\n\nGonads (ovaries/testicles) is a little more hazy. Ovaries take turns releasing eggs every other menstrual cycle. But I would guess that this is more a safety in redundancy type of thing, since biologically our body is little more than a system of keeping our sex cells alive to make sure we reproduce.\n\nHeart, liver and spleen, is simple, we only need one of them to perform the function that it does.
357835
Medical experts feel confident about most organ transplants.\n\nSuccess in this field of surgery is increasing every year.\n\nThe only organs which cannot be successfully transplanted at the moment are the brain and spinal column.\n_______________________________________________________\n\nThoracic Organs...\n...........................\nHeart (Deceased-donor only) \nLung (Deceased-donor and Living-Donor) \nEn bloc Heart/Lung (Deceased-donor only) \n__________________________________________________\n\nAbdominal Organs....\n...............................\nLiver (Deceased-donor and Living-Donor) \nKidney (Deceased-donor and Living-Donor) \nPancreas (Deceased-donor and rarely Living-Donor) \nSmall bowel (Small Intestine) (Deceased-donor and Living-Donor) \nKidney-Pancreas (Sometimes simultaneous, sometimes in separate procedures) (Deceased-donor, Living-Donor, and combined deceased/living (e.g. kidney from living donor, pancreas from deceased donor)) \nCombined Liver-Kidney (Generally Deceased-donor only) \nCombined Liver-Small Bowel (Deceased-donor only) \n_________________________________________________\n\nOther Organs.........\n.................................\nHand (Deceased-donor only) \nCornea (Deceased-donor only) \nSkin graft including Face transplant (almost always autograft) \n[edit]\nTissues, Cells, and Fluids\nIslets of Langerhans (Pancreas Islet Cells) (Deceased-donor and Living-Donor) \nBone marrow/Adult stem cell (Living-Donor and Autograft) \nBlood transfusion/Blood Parts Transfusion (Living-Donor and Autograft) \nBlood vessels (Autograft and Deceased-Donor) \nHeart valve (Deceased-Donor, Living-Donor and Xenograft[Pig]) \nBone (Deceased-Donor, Living-Donor, and Autograft) \nSkin (Deceased-Donor, Living-Donor, and Autograft) \n\n________________________________________________________\n\nCheck out this link...it's pretty cool ;\n\nhttp://en.wikipedia.org/wiki/Organ_transplant#Major_Organs_and_Tissues_Transplanted
68383
Heart, Brain, Spleen, Kidney, Blood, etc.\n\nJust kidding.\n\nMy son now that I have one.  Without him I'd not have any use for anything.
514687
All mammals are set up on a bilateral plan. Two arms, two legs, two eyes, two ears, two nostrils, two halves of the mouth and ideally are identical on either side. It has to do with the way the cells divide. So, humans would have to have an even number of nipples to maintain this symmetry.
281754
The spleen and the stomach are under the rib cage on the left side....pancreas is more midline....liver and gallbladder are right sided.\n\nSpleen:  Upper left quadrant, left hypochondriac region, articulated with ribs 9-11 (laterally). \nhttp://www.geocities.com/doctor_uae/abdomen.htm\n\nPS:  the link supplied by the person above me is a good one, but you have to realize this.  You have to look at that drawing like you are looking at an actual person.  So, the liver is on the person's right side, not on the viewer's right side....
1063237
I have never heard of a person being able to have more than one heart transplant. You are certainly a blessed man. Here are a few links to stories about people who received two organ transplants. I hope you find these stories helpful. Please try to speak with the doctor handling your case as he would be the best person to give you a prognosis.\n\nGood luck...\n\nhttp://www.sbhcs.com/services/renal/newsletter/issue_7/gift.html\n\nhttp://www.transplantweek.org/members/vol2/news/013605.htm\n\nhttp://www.aetnapharmacy.com/AP/ihtAP/r.WSIHW000/st.9339/t.32966.html
455801
Frogs have a three-chambered heart, consisting of two atria and a single ventricle. Blood leaving the ventricle passes into a forked aorta, where the blood has an equal opportunity to travel through a circuit of vessels leading to the lungs or a circuit leading to the other organs. Blood returning to the heart from the lungs passes into one atrium, while blood returning from the rest of the body passes into the other. Both atria empty into the single ventricle. While this makes sure that some blood always passes to the lungs and then back to the heart, the mixing of oxygenated and deoxygenated blood in the single ventricle means the organs are not getting blood saturated with oxygen. Still, for a cold-blooded creature like the frog, the system works well.
682856
Common animal (including human) organs include the heart, lungs, brain, eye, stomach, spleen, pancreas, kidneys, liver, intestines, skin, uterus, and bladder.\n\nBlood vessels exist in varying calibers:\n\nArteries \nAorta (the largest artery, carries blood out of the heart) \nBranches of the aorta, such as the carotid artery, the subclavian artery, the celiac trunk, the mesenteric arteries, the renal artery and the ileac artery. \nArterioles \nCapillaries (the smallest blood vessels) \nVenules \nVeins \nLarge collecting vessels, such as the subclavian vein, the jugular vein, the renal vein and the iliac vein. \nVenae cavae (the 2 largest veins, carry blood into the heart)
775861
After conception, the single fertilized egg begins to multiple and divide. Up to a point all of the cells are identical. That is why it is possible to have identical twins.  If at some point the dividing cells increase their number so suddenly that a section of cells actually get  bumped away from the main body of cells the second set of cells are identical to the first. If that second set can attach to the wall in time it will develop into an identical twin.\n\nAt this point the identical cells are called STEM cells. They have no individual identity and they are completely interchangeable.  \n\nIt is a mystery that still puzzles researchers as to how the "triggers"  turn on to tell one area of cells to become brain, another liver, another lungs, etc.  But they do.  The really amazing thing about that is that the body produces those cells even after we are born. I believe it occurs in the bone marrow.\n\nResearchers are trying to find ways to coax those stem cells out of our body and place them into damaged areas to create new cells. Stem cells inserted into a dieing pancreas will become pancreas cells because they take on the identity of whatever cells they come into contact with.\n\nThey could be inserted into a diseased heart or lungs, or liver to grow new healthy cells.\n\nThey all carry the same genes because they come from the same donor. \n\nIt truly is a mystery....
599187
The liver is the largest internal organ and it resides immediately under the right side of your diaphragm, a flat muscle separating your thorax (chest) from your abdomen.  It tucks up under the right ribs and extends across the midline and a small lobe extends almost to the spleen on the left.  A typical size for an adult liver is 1800 grams.
225583
????\nI don't understand your question...whatcha mean one organ? The human body has many organs...are you saying this person only has one organ left in their body? Sounds to me, their lucky to even be alive.
449077
We don't. \n\nThe body usually finds stuff to fill up the space with. In the abdomen (peritoneal cavity), the guts just slither around into the space formerly occupied by, say, the spleen. The kidneys are in the retroperitoneal space and if you take one out the space just heals together. If you take out the uterus (which is pretty small anyway), the bladder has a bit more room.\n\nI work in the brain. If you take out a large chunk (e.g. for tumor, epilepsy surgery, or after traumatic injury) there is a space left. We fill it up with sterile saline at operation as best we can, though there's always a bit of air left (because of gravity and water level), but over the next day or so the body replaces it with the normal cerebrospinal fluid anyway. You can image these people later, and it's just a big fluid space there.
964941
an organ which has an immune role and also destroys aged red blood cells.  This can be doen by the liver if spleen removed
598020
The two kidneys of humans are located behind the abdomen.  The kidneys regulate how much water, sodium, potassium, calcium, and phosphate are in the blood.  The kidneys also remove waste products from the body such as uric acid.  Each kidney is filled with capillaries wrapped around very tiny nephrons which filter the blood.
656861
This is a problem. Medical dictionaries define an organ as a relatively independent part of the body that carries out 1 or more special functions. Lists of internal organs usually list 22. The skin would make 23. Eyes and ears are certainly organs and in the skin are sense organs. So there isn't a definite answer or an official answer.
1059236
Spleen is useful to\n \n1) filter for your blood, cleansing it of bacteria, viruses and other debris. When blood flows through your spleen, white blood cells attack and remove any foreign invaders. This keeps your blood clean and helps protect you against infection.\n\n2) Destroying old red-blood cells\nRed blood cells have a lifespan of around 120 days, after which your spleen breaks them down. The red blood cell remains are transported elsewhere in your body where they are excreted or recycled to manufacture new red blood cells.\n\n3) Making blood cells\nBefore birth, foetuses produce red and white blood cells in their spleens. Shortly before birth the spleen loses its ability to make red blood cells and bone marrow takes over this job. The spleen continues producing infection-fighting white blood cells throughout our lives.\n\nWhat happens if spleen is removed (Living without a spleen)\nIt is possible to live without a spleen as most of its functions can be taken over by other organs. However, people without spleens are more vulnerable to all kinds of infections.
646007
Organs:\n1.  Brain\n2.  Voice Box\n3.  Lungs\n4.  Heart\n5.  Liver\n6.  Spleen\n7.  Stomach \n8.  Kidnets\n9.  Large Intestine\n10. Small Inestine\n11. Skin\n12. Bladder\n13. Gallbladder\n14. Pancreas\n15. Female/Male Genitals\n16. Appendix\n\nOrgan Systems:\n1.  Circulatory\n2.  Digestive\n3.  Endocrine\n4.  Integumentary\n5.  Muscular \n6.  Nervous: \n7.  Reproductive\n8.  Respiratory \n9.  Skeletal\n10. Urinary/Excretory: \n\nthere's 12 but I left out 2, sorry, dont want to double check to find the other two, look urself...