The spleen has a capsule made of elastin and smooth muscle.  Why would the spleen want to contract?
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One of the various functions of the spleen is a store house for blood.  In the event you have a sudden drop in blood pressure due to the loss of blood or some other form of shock, it can in effect increase your circulating blood volume by forcing blood from the organ into the blood vessels.  It's sort of like giving yourself a transfusion in an emergency.
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The human spleen is located in the upper left part of the abdomen, behind the stomach and just below the diaphragm.
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Muscular System\n\nMuscle tissue can be organized into separate muscles that are considered individual organs. Together, they form the muscular system.The cells in a muscle have two major duties: movement and heat production. Although the joints of the skeletal system allow movement, they cannot make the movement themselves. For this they require the contraction of striated muscle. Movement inside the body cavity is provided by muscles made up of smooth muscle cells. For example, the movement of food through the digestive tract is provided by the smooth muscles in the esophagus, stomach, and intestines. Urine is moved through the urinary system by smooth muscles in the ureters, bladder, and urethra. Air is moved in and out of the lungs by smooth muscle in the diaphragm. The muscular system also serves as the major heat generator for the body, keeping tissues warm.\n\nMuscle is made almost entirely of protein. When protein intake through food is low or when food protein is not digested or absorbed properly, it must come from some other source. That source is the muscle tissue. Even when enough protein is provided by the diet, cancer cells will raid the muscles for protein to change into glucose. When muscle tissue decreases, the individual muscle is less able to perform its job, causing weakness in movement and the sensation of coldness due to loss of heat production. Although cancer of the muscular system is very rare, cancer in general can cause a serious loss of muscle tissue.\n\nEndocrine System\nThe endocrine system includes the pituitary and pineal glands; the hypothalamus, thyroid, and adrenal glands; the pancreas; and the testes or ovaries and placenta. These glands release their hormones into the bloodstream directly, as opposed to the exocrine glands, which release their products into ducts. The cell citizens of an endocrine gland are writers. They compose messages called hormones, which are distributed primarily through the bloodstream. Glands perform the same job as the nervous system: communication, integration, and control of bodily functions. The signals travel slower but are much longer lasting. Hormones are the main regulators of metabolism, growth and development, and reproduction.\n\nEndocrine cell tumors are called carcinoids. Cancers of the endocrine system include the following:\n\nGerm cell cancers—These include testicular cancer (male), gestational trophoblasic neoplasms (placental), and ovarian cancer (female). Pancreatic cancer—Over 90 percent of the carcinomas of the pancreas are mucinous adenocarcinomas that originate in the pancreatic duct. Thyroid cancer. Because they stimulate abnormal hormone production, cancers of the endocrine system are often able to produce symptoms in distant sites.\n\nHope this helps, good luck.
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Endoplamsic reticulum (ER) is explained above.\nExamples of reticuloendothelial systems are the Liver and the Spleen. On microscopic examination, these organs show a strange structural organization. Cells form extensive hollow cannals that allow blood to pass through. You may describe it as sinusoidal. These cannals act like blood vessels but are not blood vessels.
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Arteries are composed of three layers. The middle layer is smooth muscle, and it works to control blood flow maintain blood pressure. The inner layer is made up of a smooth layer of endothelial cells which allow blood to flow freely through the artery.\n\nAs you age, the inner layer of endothelium becomes leaky, whichs allows fats and toxins to pass through the endothelial layer and into the smooth muscle cells. Your body mounts an immune response against these molecules, which causes the wall of the artery to become inflammed. \n\nIn an effort to plug the holes, the smooth muscle cells begin to produce a collagen cap over the leaks. Eventually, a plaque forms. Vascular calcification occurs when calcium is deposited on these plaques, causing a hardening of the arterial wall. If the plaque is loosened and breaks free into the blood stream, it can cause a stroke or heart attack.
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its a substance in the blood that keeps it from loosening or flowing continuously.
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Once again you asked a question that makes no sense whatsoever.  There's no such thing as "gibberline" but there is a plant growth product called gibberellin.  You can't mean THAT, can you?  Why would anyone combine white blood cells with plant food???
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Beware!  The other answer did not mention cardiac muscle cells.  These are different to smooth muscle and skeletal muscle types.\n\nThe 2 types are probably cardiac muscle and endomysial tissue, which seems to be a sort of connective tissue, containing blood vessels etc; see:\n\nhttp://web.upstate.edu/feiglind/index13.html
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A woman's uterus contracts slightly in order to shed the lining (which is seen as "blood").  These contractions can be an annoyance to some, and very painful for others.  The discomfort is controllable by medication.
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Hi,\nPerhaps it could be adhesions from past surgery. i have recently been reading about the scar tissue that can form after surgery and can somehow attach tissue to bowel or other internal organs or internal walls. Im sorry I do not know a lot about it but perhaps it would be worth looking up.
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One of the jobs of the spleen is to strain out any red blood cells that are irregularly shaped (in a healthy adult that would mean old cells that need to be replaced)  With an enlarged spleen there can be congestion of red blood cells.  If too many cells are collecting in the spleen then they are not circulating carrying oxygen...and the body can not replace them fast enough to compensate.  That is why if your spleen is enlarged it could affect your ability to perfuse your tissues adequately...but in humans it would be an extreme case of exertion before this would become an issue.
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The penis is made from a spongy tissue. When a male gets sexually excited, this tissue gets filled with blood and the penis hardens as a result.
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Its mostly spongy erectile/vascular tissue - it fills with blood to make it erect.\n\nhttp://en.wikipedia.org/wiki/Penis
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It's the parotid gland....it contracts (sometimes painfully) when u eat something sour....
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To save heat for the vital organs of the body, blood vessels on the skin contract, leaving you with bigger bumps.
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The endothelial-capsular membrane acts as a filter for the blood. \n\nThe endothelium prevents passage of the formed elements from the blood into the filtrate, but allows all other blood components to pass. \n\nThe basement membrane of the \n\nThe glomerulus consists of the fused basement membranes of the endothelium and the visceral layer epithelium of Bowman's capsule.  It acts to restrict passage of the larger plasma proteins but allows all other solutes to pass into the filtrate. \n\nWith these barriers to filtration, the formed elements and plasma proteins remain in the blood of the glomerulus while all other solutes freely pass from glomerulus into the filtrate.  \n\nhttp://www.apsu.edu/thompsonj/Anatomy%20&%20Physiology/2020/2020%20Exam%20Reviews/Exam%204/CH25%20Nephron%20I%20-%20Renal%20Corpuscle.htm
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this is caused from strenuous lifting. when too much pressure is placed on the stomach muscles during lifting it causes tear in the lining pushing out fatty tissue and on occasion the intestines