The human body is a complex, h... free essay sample

The human body is a complex, highly organized structure made up of unique cells that work together to accomplish the specific functions necessary for sustaining life. Our bodies consist of a number of biological systems that are vital to our survival and well-being, each system require support and coordination of other systems to form a living and healthy human body. If any of these systems is damaged, the human body will become unstable and this lack of stability will ultimately lead to death. The instability caused by damage of one system cannot be stabilized by other systems because functions of one system cannot be performed by another. One main system is the Endocrine system which is vital in maintaining homeostasis in the human body. This system influences almost every cellular function in our body; this system plays a role in regulating mood, growth and development, tissue function, metabolism, and sexual function and reproductive processes. Throughout this essay I will be talking about an organ in the endocrine system called the Adrenal gland which main role is to relay chemical messages know as hormones throughout the body.The adrenal gland is one of the major organs in the endocrine system, the adrenal gland is a pair of triangular shaped glands each about 2 inches long and 1 inch wide that sits on top of the kidneys. Dont let their small size fool you; these powerful little adrenal glands manufacture and secrete steroid hormones such as cortisol, estrogen and testosterone that are essential for life, health and vitality. They modulate the functioning of every tissue, organ and gland in your body to maintain homeostasis during stress and keep you alive. They also have important effects on the way you think and feel. The main purpose of your adrenals is to enable your body to deal with stress from every possible source, ranging from injury and disease to work and relationship problems. They largely determine the energ y of your bodys responses to every change in your internal and external environment. Whether they signal attack, retreat or surrender, every cell responds accordingly, and you feel the results. It is through the actions of the adrenal hormones that your body is able to mobilize its resources to escape or fight off danger (stress) and survive. The adrenaline hormone prepares our body to function at maximum efficiency by increasing our heart beats, breathing rate, and blood flowing muscles and causes the liver to put more stored glucose into our blood. All of these actions cause our body to produce a lot of energy rapidly and the energy helps us cope with these different situations.The adrenal gland is made up of two major regions which is the adrenal cortex and the adrenal medulla. These two major regions are encapsulated by connective tissue known as the capsule. The adrenal cortex is the largest gland and is essential to life, it controls the electrolyte and water distribution in the body and maintains proper carbohydrate balance. Its composed of three concentric zones, the zona glomerulosa (outer zone) which secretes mineralocorticoids; it affects mineral levels of sodium and potassium in the blood. The zona fasciculata (middle zone) which secretes glucocorticoids, it suppresses the immune system, and aids in metabolism which helps us generate energy from non-carbohydrate foods and even regulate our blood pressure. Lastly the zona reticularis (inner zone) which secretes dehydroepiandrosterone (DHEA) and androstenedione from cholesterol. These androgens are released into the bloodstream and transported to gonads where they are converted into testosterone or oestrogen. The hormones thats being released in this zone is mainly responsible for the development of sexual characteristics during puberty. The Adrenal medulla is the inner part of the gland and does not perform any vital functions, but just because it doesnt perform functions that you need to live doesnt mean its useless. Its composed of cells called ch romaffin cells, which are organized in clusters around blood vessels. The hormones that are produced in this part of the gland is epinephrine and norepinephrine which prepare the body to fight or flight response by increasing your heart rate, constricting blood vessels, increasing the metabolic rate heightening cognitive awareness and increasing the respiratory rate. Its very important for your body to produce these specific hormones because it can result in certain disorders. A disease that is caused from the failure of the adrenal glands is called Addisons disease, which is a rare uncommon condition in which your adrenal glands produces insufficient levels of cortisol and aldosterone. There are two major classifications for Addisons disease which is primary adrenal insufficiency and secondary adrenal insufficiency. Primary adrenal insufficiency which occurs when your adrenal glands are damaged so severely that they can no longer produce hormones. Its most often caused when your immune system attacks the adrenal glands known as autoimmune disease. I n an autoimmune disease, your bodys immune system mistakes any organ or area of the body for a virus, bacteria, or another outside invader. Secondary adrenal insufficiency which occurs when the pituitary gland located in your brain cant produce adrenocorticotropic hormone which tells the adrenal gland when to release hormones.The endocrine system is unique because its organs are not anatomically related. Hormones are produced in a wide variety of locations and can have wide reaching effects throughout the entire body.