Many infections and cancers in non-vital organs are life threatening, especially without prompt treatment. Injuries to non-vital organs may also affect vital organs, such as when a gallstone undermines liver function. Small and pear shaped, the gallbladder sits in the right upper quadrant of the abdomen, just under the liver. It contains cholesterol, bile salts, bile, and bilirubin. In a healthy person, the liver releases bile into the gallbladder, which the gallbladder stores and then releases to travel down the common bile duct into the small intestine to aid digestion.
However, some people develop gallstones that block the gallbladder or biliary tree, causing intense pain and interfering with digestion. Also, this can sometimes interfere with liver or pancreas function. Learn about some potential gallbladder issues here. Located in the upper left portion of the abdomen, the pancreas has two important roles: It functions as both an exocrine gland and an endocrine gland.
As an exocrine gland, the pancreas produces enzymes a person needs to help digest their food and convert it into energy. Those enzymes include amylase, lipase, trypsin, and chymotrypsin.
In its role as an endocrine gland, the pancreas also produces and releases insulin, which helps the body remove glucose from the blood and convert it into energy. Problems with insulin can lead to a dangerously high level of blood glucose and the onset of diabetes.
The main pancreatic duct connects to the common bile duct, which flows from the liver and gallbladder. Therefore, problems within the biliary tree, liver, or gallbladder may also affect the pancreas. Learn more about the pancreas here. Food begins its journey to the stomach soon after a person swallows. The food moves down from the throat and into the esophagus. The stomach is located at the end of the esophagus.
The muscles of the stomach help it break down and digest food. Within its lumen lining, certain regions of the stomach also produce enzymes that help digest food. The enzyme pepsin, for example, breaks down proteins so that they can become amino acids. The stomach also helps store chyme until it moves to the intestines. Chyme refers to food that has mixed with stomach secretions.
Anatomists usually divide the stomach into five subparts. The intestines are a group of tubes that help filter out waste, absorb water and certain electrolytes, and digest food. Partially digested food first travels through the small intestine, which comprises three parts: the duodenum, the jejunum, and the ileum. Most digestion and absorption of food happens here. Food then becomes feces as it travels within and through the large intestine.
This begins with the cecum, extends to the rest of colon, and ends with the rectum. The rectum is the last stop for feces before expulsion occurs from the anus.
Doctors usually list dozens of organs, though the definition of an organ varies from expert to expert. Most organs play a role in organ systems, which work together to perform specific functions.
The brain and spinal cord form the central nervous system, which works to process and send nerve signals, interpret information, and produce conscious thought. The portion of nervous system that communicates with the central nervous system is called the peripheral nervous system. Overall, the peripheral and central nervous systems also include an extensive network of neurons.
Located throughout the body, these fibrous bundles send information about sensation, temperature, and pain. For instance, the stomach releases the hormone ghrelin , which signals to the brain that it is time to eat.
This causes feelings of hunger and encourages a person to eat, which leads to the beginning of the process of digestion. The nervous system integrates with virtually every other part of the body. For example, nerve fibers in the hand tell the brain when there is an injury in that area.
Meanwhile, nerves in the skin relay information about external temperature. This may cause the brain to initiate involuntary responses that control body temperature, such as sweating or shivering.
Learn more about the central nervous system here. The reproductive system includes the organs that enable a person to reproduce and experience sexual pleasure. In females, the reproductive system also supports the growth of a fetus. The reproductive system works closely with other organs and organ systems. For example, the hypothalamus and pituitary gland help regulate the production and release of hormones such as estrogen and testosterone.
The male reproductive system organs include:. Display the questions and add further questions to the list as they arise from these discussions and observations. As a class, complete a bundling activity sorting the questions. Students should discuss what groupings to use. These questions can then inform planning of further investigations.
Revisit these questions at the end of each session and respond where appropriate with new information. These changing body displays become an integral part of the ongoing investigation and demonstrate a dynamic, changing display. To assist students to construct richer personal meanings for ideas and concepts related to internal body organs encourage them to complete sentence stems.
Sentence stems are incomplete statements designed to provide a structure for insights and observations. When students are familiar with a variety of major internal organs, provide activities that encourage students to consider how one organ is similar to or contributes to the work of another organ. Other questions might include:. Identify diseases and conditions commonly associated with each major organ, such as heart attack, asthma, stomach ulcer, etc.
Discuss contributing factors to these, such as inherited conditions. Explore how medicine has developed effective treatments for many of these, for example transplants, mechanical hearts and medication. Our website uses a free tool to translate into other languages. This tool is a guide and may not be accurate. For more, see: Information in your language. You may be trying to access this site from a secured browser on the server.
Please enable scripts and reload this page. Although no one knows where the number originates, the general count is 78 organs, she said. This list includes the vital organs: the tongue, stomach , thyroid, urethra , pancreas , plus many other single or pairs of organs.
Bones and teeth are each counted only once. Among anatomists, viewpoints differ on what counts as an organ. A histologist like Lee, who studies tissue at the microscopic level, may have a longer list of organs than a gross anatomist, who studies what's visible to the unaided eye. For example, scientists made headlines in for labeling the mesentery , which attaches the intestines to the abdominal wall, as an organ. Even though the scientists provided new evidence to call it an organ, it was not controversial, as many histologists and anatomists agreed, Lee explained.
But there's no group charged with keeping an official count of the organs or deciding what qualifies as an organ. Thinking microscopically, when multiple types of tissues join together and function together, the unit is an organ, she said. Lee could call a nail, or structures that support the nail, an organ, and count each tooth as an individual organ. It's loads more than you think. Counting each tooth separately brings the list to organs. Many other organs are listed only once, even though there are many of them throughout the body.
For instance, ligaments and tendons could dramatically increase the total number of organs when counted individually. This game is endless. The list of 78 counts the nerves just once, but there are trillions of them.
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