Endocrine Glands And Their Hormones Table Pdf
File Name: endocrine glands and their hormones table .zip
- Human endocrine system
- Hormones and the Endocrine System
- Endocrine System Overview
- Endocrine Glands & Their Hormones
Human endocrine system
Communication is a process in which a sender transmits signals to one or more receivers to control and coordinate actions.
Together, these two systems are primarily responsible for maintaining homeostasis in the body. The nervous system uses two types of intercellular communication—electrical and chemical signaling—either by the direct action of an electrical potential, or in the latter case, through the action of chemical neurotransmitters such as serotonin or norepinephrine.
Neurotransmitters act locally and rapidly. When an electrical signal in the form of an action potential arrives at the synaptic terminal, they diffuse across the synaptic cleft the gap between a sending neuron and a receiving neuron or muscle cell.
Once the neurotransmitters interact bind with receptors on the receiving post-synaptic cell, the receptor stimulation is transduced into a response such as continued electrical signaling or modification of cellular response. In this way, neural communication enables body functions that involve quick, brief actions, such as movement, sensation, and cognition. In contrast, the endocrine system uses just one method of communication: chemical signaling.
These signals are sent by the endocrine organs, which secrete chemicals—the hormone —into the extracellular fluid. Hormones are transported primarily via the bloodstream throughout the body, where they bind to receptors on target cells, inducing a characteristic response. As a result, endocrine signaling requires more time than neural signaling to prompt a response in target cells, though the precise amount of time varies with different hormones. For example, the hormones released when you are confronted with a dangerous or frightening situation, called the fight-or-flight response, occur by the release of adrenal hormones—epinephrine and norepinephrine—within seconds.
In contrast, it may take up to 48 hours for target cells to respond to certain reproductive hormones. Visit this link to watch an animation of the events that occur when a hormone binds to a cell membrane receptor. What is the secondary messenger made by adenylyl cyclase during the activation of liver cells by epinephrine?
In addition, endocrine signaling is typically less specific than neural signaling. The same hormone may play a role in a variety of different physiological processes depending on the target cells involved. For example, the hormone oxytocin promotes uterine contractions in women in labor. It is also important in breastfeeding, and may be involved in the sexual response and in feelings of emotional attachment in both males and females.
In general, the nervous system involves quick responses to rapid changes in the external environment, and the endocrine system is usually slower acting—taking care of the internal environment of the body, maintaining homeostasis, and controlling reproduction Table So how does the fight-or-flight response that was mentioned earlier happen so quickly if hormones are usually slower acting?
It is because the two systems are connected. It is the fast action of the nervous system in response to the danger in the environment that stimulates the adrenal glands to secrete their hormones. As a result, the nervous system can cause rapid endocrine responses to keep up with sudden changes in both the external and internal environments when necessary. The endocrine system consists of cells, tissues, and organs that secrete hormones as a primary or secondary function.
The endocrine gland is the major player in this system. The primary function of these ductless glands is to secrete their hormones directly into the surrounding fluid.
The interstitial fluid and the blood vessels then transport the hormones throughout the body. The endocrine system includes the pituitary, thyroid, parathyroid, adrenal, and pineal glands Figure Some of these glands have both endocrine and non-endocrine functions. For example, the pancreas contains cells that function in digestion as well as cells that secrete the hormones insulin and glucagon, which regulate blood glucose levels.
The hypothalamus, thymus, heart, kidneys, stomach, small intestine, liver, skin, female ovaries, and male testes are other organs that contain cells with endocrine function. Moreover, adipose tissue has long been known to produce hormones, and recent research has revealed that even bone tissue has endocrine functions. Examples of exocrine glands include the sebaceous and sweat glands of the skin. As just noted, the pancreas also has an exocrine function: most of its cells secrete pancreatic juice through the pancreatic and accessory ducts to the lumen of the small intestine.
In endocrine signaling, hormones secreted into the extracellular fluid diffuse into the blood or lymph, and can then travel great distances throughout the body.
In contrast, autocrine signaling takes place within the same cell. Interleukin-1, or IL-1, is a signaling molecule that plays an important role in inflammatory response. The cells that secrete IL-1 have receptors on their cell surface that bind these molecules, resulting in autocrine signaling.
Local intercellular communication is the province of the paracrine , also called a paracrine factor, which is a chemical that induces a response in neighboring cells.
Although paracrines may enter the bloodstream, their concentration is generally too low to elicit a response from distant tissues. A familiar example to those with asthma is histamine, a paracrine that is released by immune cells in the bronchial tree.
Histamine causes the smooth muscle cells of the bronchi to constrict, narrowing the airways. Another example is the neurotransmitters of the nervous system, which act only locally within the synaptic cleft.
Endocrinology is a specialty in the field of medicine that focuses on the treatment of endocrine system disorders. Endocrinologists—medical doctors who specialize in this field—are experts in treating diseases associated with hormonal systems, ranging from thyroid disease to diabetes mellitus.
Endocrine surgeons treat endocrine disease through the removal, or resection, of the affected endocrine gland. Patients who are referred to endocrinologists may have signs and symptoms or blood test results that suggest excessive or impaired functioning of an endocrine gland or endocrine cells.
Treatment varies according to the diagnosis. Some endocrine disorders, such as type 2 diabetes, may respond to lifestyle changes such as modest weight loss, adoption of a healthy diet, and regular physical activity. Other disorders may require medication, such as hormone replacement, and routine monitoring by the endocrinologist. These include disorders of the pituitary gland that can affect growth and disorders of the thyroid gland that can result in a variety of metabolic problems.
Some patients experience health problems as a result of the normal decline in hormones that can accompany aging.
These patients can consult with an endocrinologist to weigh the risks and benefits of hormone replacement therapy intended to boost their natural levels of reproductive hormones. In addition to treating patients, endocrinologists may be involved in research to improve the understanding of endocrine system disorders and develop new treatments for these diseases.
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Table of contents. Levels of Organization. Support and Movement. Regulation, Integration, and Control. Fluids and Transport. Energy, Maintenance, and Environmental Exchange.
Human Development and the Continuity of Life. By the end of this section, you will be able to: Distinguish the types of intercellular communication, their importance, mechanisms, and effects Identify the major organs and tissues of the endocrine system and their location in the body. Endocrine and Nervous Systems. Table Figure Endocrinologist Endocrinology is a specialty in the field of medicine that focuses on the treatment of endocrine system disorders.
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Hormones and the Endocrine System
Endocrine Community. Email Print Discuss. Written by Robert M. Sargis MD, PhD. Simply put, the endocrine system is a network of glands that secrete chemicals called hormones to help your body function properly. Hormones are chemical signals that coordinate a range of bodily functions. The endocrine system works to regulate certain internal processes.
The endocrine system is made up of the endocrine glands that secrete hormones. Although there are eight major endocrine glands scattered throughout the body, they are still considered to be one system because they have similar functions, similar mechanisms of influence, and many important interrelationships. Some glands also have non-endocrine regions that have functions other than hormone secretion. For example, the pancreas has a major exocrine portion that secretes digestive enzymes and an endocrine portion that secretes hormones. The ovaries and testes secrete hormones and also produce the ova and sperm. Some organs, such as the stomach , intestines, and heart , produce hormones, but their primary function is not hormone secretion.
Endocrine System Overview
Human endocrine system , group of ductless glands that regulate body processes by secreting chemical substances called hormones. Hormones act on nearby tissues or are carried in the bloodstream to act on specific target organs and distant tissues. Diseases of the endocrine system can result from the oversecretion or undersecretion of hormones or from the inability of target organs or tissues to respond to hormones effectively.
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Endocrine Glands & Their Hormones
The endocrine system is a network of glands and organs located throughout the body. However, while the nervous system uses nerve impulses and neurotransmitters for communication, the endocrine system uses chemical messengers called hormones. Keep reading to discover more about the endocrine system, what it does, and the hormones it produces.
The pituitary gland or hypophysis is an endocrine gland about the size of a pea and weighing 0. It is a protrusion off the bottom of the hypothalamus at the base of the brain , and rests in a small, bony cavity sella turcica covered by a dural fold diaphragma sellae. The pituitary is functionally connected to the hypothalamus by the median eminence via a small tube called the infundibular stem or pituitary stalk. Reduces smooth muscle contractions and blood flow within the intestine.