Endocrine+System+6a

= __Th e Endocrine System__ =



The endocrine system consists of different glands that produce chemicals called hormones. Hormones help organs keep doing what they're supposed to do at the right rate. Each person has 8 glands in their body. The hypothalamus, pituitary gland, thymus gland, adrenal glands, pancreas, thyroid gland, and parathyroid glands are the ones that everyone has but females also have ovaries and males also have testes. Each of these glands help your body do different things, as you will be learning about.

__Primary Function__
The endocrine system does many things but its main functions are to produce and stop the release of hormones. These chemicals, hormones, control the body's daily functions and regulate long-term changes such as growth and development. Hormones travel in the bloodstream until they locate and lock with a "target cell." The hormone and target cell fit together like a key and lock. Once the hormone “locks” with that target cell, it can affect it in 3 main ways. The first way is in emergencies, like how adrenaline is released in sudden danger. The second way is long term, which means that it assists in things that the organ does all the time. The last way is long term and short term, which is when it assists in functions carried on in varying degrees. Aside from producing hormones, the endocrine system also stops their release. When a hormone has reached a certain level in the blood, the gland that produces that hormone uses negative feedback to halt its production. Negative feedback is when the hormone reaches a level in the blood and somehow, the gland knows to stop its production.

The endocrine system is made up of different glands, the hypothalamus, pituitary gland, thymus gland, adrenal glands, thyroid gland, parathyroid glands, testes in males, and ovaries in females. They hypothalamus is located in the lower part of your brain, and the pituitary gland has 2 glands and they are in a bony pocket in your skull. The thymus gland is behind the breastbone. The adrenal glands are on your left and right sides, just above your kidneys, and your pancreas is between them. Your thyroid gland is at the base of your neck, and has two glands on either side of your trachea. A tissue called isthmus connects these two glands. Your parathyroid glands are on the surface of your thyroid gland. Before you were born, your testes were up in your abdomen. During fetal development they descend, and once the child is born, they hang down between the boys legs. Last but not least, the ovaries are in a female’s lower abdomen. All these different organs do so many different things!

===**__Organs__ ** ===

Each of the nine glands produce hormones that control different things in your body. The hypothalamus is very important, because it controls the pituitary gland and the pituitary gland is necessary for some of the other glands to work. The pituitary gland has two lobes, a posterior (back) lobe and an anterior (front) lobe. The anterior lobe produces 5 different hormones, growth hormone, ACTH, thyrotrophic, gonadotropic, and prolactin. The growth hormone helps with growing, ACTH stimulates the adrenal glands, the thyrotrophic hormone keeps the thyroid gland healthy and stimulates it's function, the gonadotropic hormone regulates functions of the male and female reproductive organs, and prolactin tells the mammary glands in a woman's breasts to develop and after infants birth, produce milk. The posterior lobe produces 2 hormones, ADH and oxytorin. ADH regulates the water in your body and oxytorin helps push the baby out. The thyroid gland controls the release of energy from food molecules inside cells. It also produces thyroxin, which stimulates your body's metabolic functions and also produces calcitonum, which sends calcium to your bones. Parathyroid glands produce parahormone. That helps your body take in and use calcitonum and therefore regulate the amount of calcium in your blood. The thymus gland is also important; it helps your immune system during childhood. That means that when you are a child, your thymus gland is helping protect you from different diseases. Your adrenal glands to three different things, they release adrenaline when you are in sudden danger. Adrenaline makes your heart beat faster and other things that happen when you are in danger. The adrenaline glands also produce hormones that that affect the amount of salt and water in your kidneys and the sugar in your blood. Your pancreas produces insulin and glucagon. They control the level of glucose in your blood. The ovaries in woman do two things; they release female sex hormones estrogen and progesterone. Estrogen controls changes in a females body and estrogen and progesterone trigger egg development. Finally, the testes in males also do two things. They release a male sex hormone called testosterone. Testosterone controls changes in a male’s body and also regulates the sperm production.

===**__How does this system interact with other systems?__ ** ===

The different glands in the endocrine system interact with many other systems. Oxytorin, a hormone produced in the pituitary gland, interacts with the reproductive system by helping to push the baby out. Also, the pituitary gland produces the gonadotropic hormone. This also interacts with the reproductive system by regulating the functions of the male and female reproductive organs. Another thing is that the thymus gland helps the immune system during childhood. The calcitonum from the thyroid gland helps the skeletal system because it makes the bones strong and healthy. The adrenal glands affect the salt and water in kidneys, and that is helping the excretory system. One last way is that the hypothalamus links the endocrine system with the nervous system. Nerve messages come from the hypothalamus and the hypothalamus is also an endocrine system gland.

There are many ways to keep the endocrine system healthy. One way is to prevent obesity, because that leads to type two diabetes. Also, you should keep from being stressed over long periods of time. Being stressed for longer than a few hours, it means that your body needs more of the hormones that respond to stress. This makes your body weaker and it makes your body more vulnerable to diseases. Also, stress over a long period of time causes high blood pressure and a lack of other hormones released by the adrenal glands. That leads to organ damage and failure. Exercise, proper amounts of sleep, relaxation, and positive thinking all help reduce stress. Another way to keep your endocrine system healthy is to have a nutritious, healthy, and balanced diet. A lack of iodine in your diet can cause an enlargement of the thyroid gland, and nobody wants that, right?

There are many diseases that are caused by the endocrine system. Diabetes, growth hormone deficiency, hypothyroidism, and hyperthyroidism. Diabetes is a common problem with the endocrine system. There are two types of diabetes, type one and type two. Type one diabetes is caused when the cells in the pancreas are destroyed, therefore causing a lack of insulin. The lack of insulin makes it so that there is too much glucose in the blood. When the body attacks and destroys the cells in the pancreas, it causes type one diabetes. This is called autoimmune reaction. Various things cause type two diabetes. One thing that can cause it is that the receptors on the cells in the body that respond to the action of insulin fail to respond. Another cause is simply that there is not enough insulin. The last cause is that the insulin that the pancreas does produce is abnormal, so it does not function properly. Growth hormone deficiency and hypothyroidism both cause the same thing. They make a person not grow at the rate expected. Growth hormone deficiency happens when the pituitary gland does not produce enough growth hormones. Hypothyroidism happens when the thyroid gland is not producing enough thyroid hormone. Thyroid hormone is necessary to support normal growth. One last disease is hyperthyroidism, which like hypothyroidism, is also caused by the thyroid gland. Unlike hypothyroidism, it happens when the thyroid gland is producing too much thyroid hormone. When it does this, the body uses up energy more quickly than it should, and chemical activities like metabolism in the cells speed up.

===**__Conclusion__ ** ===

In conclusion, the endocrine system does many things, from helping you grow taller to helping your immune system. The hypothalamus, pituitary gland, thyroid gland, parathyroid glands, thymus gland, testes, ovaries, adrenal glands, and pancreas all produce hormones that assist your body every day. If we all suddenly didn't have endocrine systems, we wouldn't be able to survive. Everyone would have diabetes, hypo- or hyperthyroidism, growth hormone deficiency, and many more different diseases. How horrible!

Come look at my awesome web! Look at a video from kidshealth.com

__**Websites that you can go to to learn more about the endocrine system:**__ -@http://biology.clc.uc.edu/courses/bio105/endocrin.htm -@http://kidshealth.org/kid/htbw/htbw_main_page.html

__**Books that I used:**__ -Human Biology and Health by Elizabeth Coolidge-Stolz -The Human Body: an Overview by Mary Kiltlredge

__**Websites that I used:**__ -http://www.kidshealth.org/kid/body/mybody.html -http://chinese-school.netfirms.com/diabetes-causes.html