Endocrine System Essay

Endocrine System Essay The Endocrine System The body requires information in order to develop properly and maintain physiological balance. In order for the body to develop properly and maintain physiological balance it requires many different types of information. The endocrine system is one way in which these communications happen. By using hormones, organs and tissues alike contribute to the regulation of bodily processes. Hormones are chemicals that the endocrine glands excrete into intercellular spaces that then diffuse into the bloodstream. There are two types of hormones that affect how the individual hormone reacts to its specific target cell: non-steroid and steroid. Steroid hormones are lipid soluble and pass through the cell membranes, where they bind to receptors within the cells and attach to DNA molecules to activate genes (Alcamo, 2003). Because protein, or non-steroid, hormones are not lipid soluble, they must instigate chemical changes by binding to hormone receptors at the plasma membrane of their target cells. This triggers chemical reactions that activate the second messengers, molecules that continue carrying the information, for the â€Å"message† to be processed within the cell (Thibodeau Patton, 2008). In the second-messenger mechanism, it may help to remember that the non-steroid hormone acts as the first messenger, and the molecules activated by the non-steroid hormone re acting with the receptor at the cell membrane are the second messengers. The primary purpose of hormones is to affect changes in various body systems in order to create developmental changes. They are also responsible for maintaining the balance of the body as a whole. For example, the hormone epinephrine (commonly known as adrenaline), produced by the medulla of the adrenal glands, affects the sympathetic nervous system as part of a response to stress (Thibodeau Patton, 2008). While epinephrine is not currently considered a hormone that is required for living, it is one that promotes homeostasis by providing immediate bodily response to cope and survive in perceived emergency situations. The endocrine system is composed of organs and ductless glands that facilitate body development and homeostasis (Walker Wood, 2003).The primary organs of the endocrine system include the pituitary gland, hypothalamus, pineal gland, thyroid gland, parathyroid glands, thymus gland, adrenal glands, sex glands, and the pancreas. Many other organs also function in some capacity as part of the endocrine system (Davis, 2006). They may utilize typical hormones or prostaglandins, which are hormones used by tissues in order to act upon other cells within the tissue (Thibodeau Patton, 2008). The pituitary gland has been, and still often is, thought of as the â€Å"master gland† because of its role controlling the functions of many of the other endocrine glands. The pituitary gland is actually two parts: the adenohypophysis (the anterior pituitary gland), and the neurohypophysis (the posterior pituitary gland). The adenohypophysis is composed of glandular tissue and releases growth hormone (GH), prolactin, and tropic hormones that control other endocrine glands. GH promotes the breaking down of fat while slowing down the catabolism of glucose, and supports normal growth (Thibodeau Patton, 2008). Prolactin, also known as lactogenic hormone, promotes breast development and lactation in the pregnant and nursing mother. The tropic hormones secreted by the adenohypophysis are: thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). TSH stimulates growth of the thyroid gland and release of thyroid hormones. ACTH acts as TSH does with the thyroid, but for the adrenal cortex and glucocorticoids. FSH, in females, affects the growth and maturation of ovarian follicles, ovulation, and stimulates estrogen. In males, FSH stimulates sperm production. LH, like FSH, works on the reproductive organs. In females it acts with FSH to increase estrogen secretion from follicles, help follicles and ovum mature, and cause ovulation. LH also stimulates luteinization and the production of progesterone in women, and is sometimes called the â€Å"ovulating hormone† (Thibodeau Patton, 2008). For men, LH acts to instigate the development and secretion of testosterone. The posterior portion of the pituitary gland, the neurohypophysis, is made up of nervous tissue. This gland secretes anti-diuretic hormone (ADH) and oxytocin when signaled to do so by the nervous system (Walker Wood, 2003). ADH helps regulate the electrolyte balance of the body by reducing the amount of fluid urinated -as it increases how much water is reabsorbed into the body from the kidneys. Oxytocin promotes a positive feedback loop, temporarily encouraging the disruption of homeostasis, by stimulating uterine contractions during childbirth. Oxytocin also affects the cells of milk-filled breasts to encourage lactation by causing the breast milk to flow. The hypothalamus is the main reason the pituitary gland no longer has the same reputation for being the dominant endocrine gland. This is because the hypothalamus, in effect, regulates much of the pituitary gland. On top of producing the hormones the neurohypophysis secretes, the hypothalamus itself secretes hormones that act on the adenohypophysis of the pituitary gland: inhibiting and releasing hormones. The thyroid gland produces and stores the thyroid hormones thyroxine (T4) and triiodothyronine (T3), as well as secretes calcitonin. T4 and T3 increase the rate cells metabolize energy. Calcitonin promotes calcium balance in the blood by inhibiting the breakdown of bone. The parathyroid glands are located on the posterior side of the thyroid gland and are responsible for parathyroid hormone (PTH), also known as parathormone (Alcamo, 2003). PTH acts in the opposite regard as calcitonin and increases blood calcium levels by stimulating bone resorption. The thymus gland releases hormones for the development and differentiation of T cells, and is most productive in children as it is responsible for the development of the immune system. The hormones currently known to work for the thymus gland are: thymosin, thymopoietin, thymulin, thymic humoral factor, interleukins, and interferon (Eroschenko, 2008). The pineal gland regulates the internal clock through melatonin. Melatonin inhibits the adenohypophysis in releasing gonadotropins (Alcamo, 2003). Its secretion is controlled by the amount of light the eyes register. The adrenal glands are located on top of each kidney. They consist of the adrenal medulla, the core of the adrenal gland, and the outer portion of the adrenal gland known as the adrenal cortex. The adrenal medulla is the part that secretes epinephrine and norepinephrine in order to support the body in stressful situations. The adrenal cortex is made up of three layers: the outer layer (zona glomerulosa), the middle, or second, layer (zona fasciculate), and the zona reticularis -the third, innermost layer (Alcamo, 2003). The hormones these layers release are corticoids. More specifically, the corticoids each layer secretes are the mineralocorticoids, glucocorticoids, and sex hormones, respectively. Mineralcorticoids help maintain electrolyte balance. Glucocorticoids aid in the process of gluconeogenesis, which is a process whereby liver cells convert amino and fatty acids into glucose to increase blood glucose levels. The sex hormones secreted by the zona reticularis are androgens. The testes are the sex glands in the male and the ovaries in the female. The testes secrete the hormone testosterone from their interstitial spaces, or the spaces between the cells. Testosterone is a steroid hormone that regulates the secondary sex characteristics of males (Alcamo, 2003). Ovaries consist of two structures that have endocrine functions. The corpus luteum secretes primarily progesterone, but also secretes some estrogen, while the ovarian follicles secrete estrogen. Estrogen has many roles the females system, and contributes to maturation of the female reproductive organs, maintaining pregnancy, preparing the breasts for lactation, and developing the secondary sex characteristics (Walker Wood, 2003). Progesterone essentially serves to prepare the uterus for pregnancy. The pancreas acts as both an endocrine and exocrine gland. Its endocrine functions are extremely important to regulating blood glucose and ensuring cells receive sufficient energy. The pancreas has islet cell clusters, known as islets of Langerhans, which contain alpha, beta, and delta cells (Alcamo, 2003). The alpha cells secrete glucagon, which acts to increase blood glucose levels. The beta cells secrete the hormone insulin. Insulin behaves antagonistically to glucagon, so it acts to reduce glucose levels in the blood. The role of somatostatin, the hormone released by the delta cells, is still unclear, although its considered to affect the secretion of both insulin and glucagon (Alcamo). Other organs and tissues not immediately associated as endocrine organs also use hormones to regulate their functions. Among these organs are the heart and the kidneys. The heart produces atrial natriuretic hormone (ANH) to help regulate sodium in the blood, while kidneys have endocrine cells that release the hormone erythropoietin, helping bone marrow produce red blood cells (Davis, 2006). Research continues to teach new things about the endocrine system. Recently, in 2007, researchers at Columbia University Medical Center determined that the skeleton also performs endocrine functions by regulating blood sugar (Ballantyne). Until research reveals new information, it can be hard to define how much is still unknown about the endocrine system. Additionally, there are unanswered question concerning what is currently known such as â€Å"what is the purpose of androgens in males?† and â€Å"what does somatostatin really do? The structure of the endocrine system is unique in that most of its organs arent actually physically attached to each other. Another interesting attribute of this system is that many other body systems also contribute to endocrine functions. This allows for the organs to communicate more quickly in localized systems, such as in the case of endocrine functions in the digestive system. The endocrine system serves to communicate with a broader group of cells, more gradually and more long-term, than the other primary communication system of the body: the nervous system (Walker Wood, 2003). The chemical transmission of information this system provides aids the body in balancing its activities throughout the other body systems, thereby promoting homeostasis. References Alcamo, I.E. (2003). Anatomy coloring workbook (2nd ed.). New York City, NY: Princeton Review Publishing, L.L.C. Ballantyne, C. (2007). Is bone-fat chitchat the key to weight loss? Scientific American. Retrieved from http://www.scientificamerican.com. Davis, G. (2006). Hormonal control and the endocrine system: achieving homeostasis. Nurse Prescribing, 4(11), 446-453. http://search.ebscohost.com. Eroschenko, V.P. (2008) diFiores atlas of histology with functional correlations (11th ed.). Baltimore, MD: Lippincott Williams Wilkins. Thibodeau, G.A. Patton, K.T. (2008). Structure and function of the body (13th ed.). St. Louis, MO: Mosby, Inc. Walker, P. Wood, E. (2003). The endocrine system, Farmington Hills, MI: Lucent Books.

Grade 8 Graduation Speech

Grade 8 Graduation Speech Hello, graduating class of 2012! Good evening and welcome to all the parents and families who have came to this graduation ceremony today. Our parents are the people who know us the best in the whole world, even if that seems hard to believe, it's true. They've helped us become the people we are today, and they've done a great job. After all, we wouldn’t be here without them. So, thank you, parents. Today, June, 26th, 2012, is the day that we, as a class, are going to graduate the eighth grade. Of course, we all know that. But do we really understand what it all means?The definition of graduation is to complete a class or course of study. That’s it, the original definition of graduating. To me, graduation means more than that. It means growing, it means changing, and it means moving on. Today, the ceremony might seem like it's all happening too fast, or, it might seem like it's never going to end, but all our lives we'll remember it, and that's what counts. My two years of middle school have been a time to remember, I’ve learned a lot during my time in middle school, and these memories are what we are going to remember for the rest of our lives. For me, it all started on the first week of September.All I saw was these big guys playing basketball and soccer and I was wondering whether or not I will be able to fit in. Everyone else was eagerly waiting for the first school bell to ring after like 3 months of summer while I was just standing there looking everywhere as if I was lost. Eventually, all of these started to change as I started to know people better. Thing was, they weren’t as furious or mean as I thought they might be. In the beginning of the school year, I used to nervously switch classes without actually knowing where to go, but now I am familiar with this school like all the others.I managed to develop many new skills and stuff during grade 7. Before I knew it, it was June, grade 7 ended, and to m y surprise, I'd survived my first year of school in Regent Heights. When we came back from a 3 month long summer, I knew what more teachers would expect from me. 8th grade began. We were the oldest, and the wisest. It was a completely different experience for me, with all the testing for specialised program registrations. It required you to know quite few stuff ahead of what you were being taught.After all of that, term 2 came to an end, and we all started setting goals to do well on the next term. Many activities were held during spring. And as usual, it came to an end. We grew as teams and as a grade, but more importantly as people—figuratively and literally. We became smarter, more confident, and of course, taller. Together, we listened as the guidance counsellors told us about the high school and together we looked over the seemingly endless lists of classes. We turned in our worn, wrinkled, class sheets nervously, but a couple months later, all our worries were gone.Toda y, we will graduate together, in a matter of minutes, leaving behind a school, a grade, our team, and some great, great teachers. Together we will enter the high school next fall, and in four years we’ll graduate again. Senior year will be just like this one, but the intensity will be higher. I’m excited to enter high-school, I’m pretty sure it will be fun. And, I'm sure that we can handle all of it: the teachers, the seniors, and of course, the homework. So, it's time for our graduation. Here, now, today, we're ready, even though we might not know it. Let's go, and let's make today a day that we'll remember forever.

Is aid good or bad?

Aid is a form of help usually given by the wealthy areas of the world to the poorer areas. Aid tries to help countries to develop and improve their standards of living and quality life. There are many advantages and disadvantages to giving aid. The aid that we give can save lives in times of disaster! Giving aid can help to reconstruct livings and housing after a disaster. Aid can also provide medical training, medicines and equipment. This will improve health and standards of living because in other countries, medical care is very expensive and not very good.It is hard for them to get well trained staff, and the right equipment so if another country can provide this for them, they can give better quality medical attention to more people and for less money. This will save many lives because in a poor country, some people cannot afford to get help and they die, or they get attention but it is not helpful because they don’t have well trained staff, or the right medicine and equi pment. Aid for agriculture will increase food production and the quality and quantity of food available.This will also improve health and standards of living for the people who don’t have food because there will be more available. Aid for industrial development will not only improve transport organisation, but it will also create jobs for those who are jobless and who need money for their families. However, there are some disadvantages of giving aid. Giving aid can cause on Less Economically Developed Countries (LEDC’s) to rely on richer countries to supply them with all that they need. Sometimes aid is a loan, not a gift, and poor countries may find it hard to pay back what they owe.They could get so used to just getting all they need for nothing and failing to progress themselves! Another disadvantage is that the people who need aid the most, may not actually receive it. For example if medical aid was given to a country, they might use it to get well trained staff, a nd lots of equipment and medicine, just making the prices higher, causing less people being able to afford it, which leads to less people with medical attention, and more people dying or politicians could use the aid for their own means or for political gain.Or, rather than the aid helping to create more jobs, they could just use it to benefit the people who already have jobs by paying them more. Giving aid could also lead to prices of food and water going up. This could happen if the country spends a lot of money on improving the quality of the food and water then the price ends up increasing. In conclusion, although aid is not always used in the right way, I think that it is a very good thing to give. If aid is shared equally then it is very useful and will really help the country develop and improve their standards of living and quality life. Is aid good or bad? Aid is a form of help usually given by the wealthy areas of the world to the poorer areas. Aid tries to help countries to develop and improve their standards of living and quality life. There are many advantages and disadvantages to giving aid. The aid that we give can save lives in times of disaster! Giving aid can help to reconstruct livings and housing after a disaster. Aid can also provide medical training, medicines and equipment. This will improve health and standards of living because in other countries, medical care is very expensive and not very good.It is hard for them to get well trained staff, and the right equipment so if another country can provide this for them, they can give better quality medical attention to more people and for less money. This will save many lives because in a poor country, some people cannot afford to get help and they die, or they get attention but it is not helpful because they don’t have well trained staff, or the right medicine and equi pment. Aid for agriculture will increase food production and the quality and quantity of food available.This will also improve health and standards of living for the people who don’t have food because there will be more available. Aid for industrial development will not only improve transport organisation, but it will also create jobs for those who are jobless and who need money for their families. However, there are some disadvantages of giving aid. Giving aid can cause on Less Economically Developed Countries (LEDC’s) to rely on richer countries to supply them with all that they need. Sometimes aid is a loan, not a gift, and poor countries may find it hard to pay back what they owe.They could get so used to just getting all they need for nothing and failing to progress themselves! Another disadvantage is that the people who need aid the most, may not actually receive it. For example if medical aid was given to a country, they might use it to get well trained staff, a nd lots of equipment and medicine, just making the prices higher, causing less people being able to afford it, which leads to less people with medical attention, and more people dying or politicians could use the aid for their own means or for political gain.Or, rather than the aid helping to create more jobs, they could just use it to benefit the people who already have jobs by paying them more. Giving aid could also lead to prices of food and water going up. This could happen if the country spends a lot of money on improving the quality of the food and water then the price ends up increasing. In conclusion, although aid is not always used in the right way, I think that it is a very good thing to give. If aid is shared equally then it is very useful and will really help the country develop and improve their standards of living and quality life.

THE LAW OF PROPERTY Free Essay Example, 1500 words

The first is that of implied by common intention easement. This would not apply as it has come to the attention of Mrs. Batsford after the purchase and there was no common intention. The next important implied by way of easement is that of Wheeldon v. Burrows, however this rule merely applies to grant only and so Mr. Brown would not be able to use this rule in his favour as he is reserving the right of easement rather than granting it. The same principle also applies under section 62 of the Law of Property Act 1925, that is it refers merely to grants and not to reservation (Cooke 2006) As far as easements by way of prescription is concerned, it is an established principle that land which belonged to one person cannot be said to create an easement and thus Mr. Brown would not be able to rely on prescription. The next are is that of Prescription at common law which means long use. However such would require a servient owner to be separate from dominant which is not present on the facts (Cooke 2006; Chapelle 2006) Thus it would not be possible for Mr. We will write a custom essay sample on THE LAW OF PROPERTY or any topic specifically for you Only $17.96 $11.86/pageorder now Brown to claim easements in respect of the underground use of land of Mrs. Batsford after the purchase and a restriction can be be place on him by Mrs. Batsford. (iii) Under the unregistered and registered land principles, the transfer ownership or change in titles after conveyance differs and as such there have been various reforms brought about by the LRA. It is important to mention since Mr. Brown had conveyed the property, the rights and interests in the piece of land that had been conveyed had passed to Mrs. Batsford. Furthermore, even though there would be differing level of time when the title would pass, the interests had passed as the land had been conveyed and any property found therein was to be the property of Mrs. Batsford. Thus it would be irrelevant whether the land is registered or not as Mr. Brown had conveyed the property to Mrs. Batsford and she had acquired all the rights and liabilities of the piece of land. Thus she would be the rightful owner of the gold chain and claim her right of the chain unless it can be proved by Mr. Brown that he was the owner and had lost the chain. Ownership of Mr. Brown would be important because if such is shown then since the interest is not covered under the land conveyance. However, on the facts it is seen that no such ownership exists and Mr. Brown had merely found it and thus he was possibly a trespasser when he found the chain and so cannot claim the gold chain to be his.