What is the endocrine system?. Chapter 10 Regulating Body Function Working closely with your nervous system is the endocrine system, a chemical communication.

Endocrine System

What is the endocrine system?

Endocrine SystemChapter 10Regulating Body FunctionWorking closely with your nervous system is the endocrine system, a chemical communication system that regulate many body functions.

Keeps you in your happy place3Exocrine vs EndocrineExocrine GlandsEndocrinesecrete their products into ducts that empty onto a surface or into a cavity. Ex: Sweat glands and salivary glands Ductless glands. They secrete chemicals (hormones) into intracellular spaces.

notRegulating Body FunctionA gland is a group of cells, or an organ, that secretes a chemical substance. The endocrine glands secrete chemicals called hormones directly into the bloodstream. The blood carries the hormones directly to the tissue they are targeted to affect. Some hormones are produced continuously, while others are produced only at certain times.

Regulation of Hormone SecretionNegative FeedbackPositive FeedbackHomeostatic control mechanism that reverses what is happening in the body More common than positive feedback. Ex: Insulin, Body Temperature, Blood Pressure

Amplifies changes rather than reverses them. Ex: Labor amplified contractions.Discuss target cells6Mechanisms of Hormone ActionNonsteroid HormonesSteroid HormonesProteinSecond messenger mechanism: nonsteroid hormones serve as 1st messenger between gland and cells; Another molecule will then act as a 2nd messenger providing communication within the target cellLipid-solubleCan pass through cell membrane of target cellBind with receptors on the nucleus and act on DNAMeet the GlandsEndocrine SystemBut first.

PituitaryThe pituitary gland at the base of the brain is a gland that signals other endocrine glands to produce hormones when needed. It is also known as the Master Gland and is located at the base of the brain. It secretes several hormones. These regulate the thyroid gland, adrenal glands, and kidneys- plus your growth and development. It produces growth hormones.

PituitaryAnteriorPosteriorTSHThyroid stimulating ACTHAdrenocorticotropicFSHFollicle-stimulatingLHluteinizingGHgrowthProlactin

ADHAnti-dureticOxytocin

HypothalamusThe hypothalamus is a vital neuroendocrine and autonomic control center beneath the thalamus.Secretes:Releasing hormonesAnterior pituitaryInhibiting hormonesPosterior pituitary

ParathyroidThe parathyroid glands direct the distribution of certain minerals in your body.Increase Ca+ in bloodSecretesParathyroid hormone or PTH

Calcium Reabsorption

PancreasThe pancreas is part of two body systems- the digestive system and the endocrine system. It is located behind the stomach and supplies the small intestine with digestive juice. It produces insulin and contains small clusters of cells called the islets of Langerhans, which control blood sugar levels. It produces insulin.

PancreasHow Insulin Works

ThymusThe thymus gland is located in the mediastinum.It is a vital part of the bodys immune system.Produces thymosin

Pineal GlandThe pineal gland is located in the third ventricle of the brain.It produces melantonin.

ThyroidThe thyroid gland is located where the larynx and trachea meet. It regulates the chemical reactions of nutrients in the cells. It produces thyroxine.

AdrenalThe adrenal glands are located on your kidneys. They secrete hormones that help the body maintain its levels of sodium and water, aid the digestive process, and control your bodys response to emergencies. It produces adrenaline.

Adrenal

The Bodys Response to StressWhen your brain recognizes a stressful situation, your adrenal glands responds by releasing the hormone adrenaline. This hormone prepares your body to respond to stress.

ReproductiveDuring adolescence, the endocrine system plays an important role in growth and development.

OvariesThe ovaries are the female reproductive glands. They control the development of secondary sex characteristics during adolescence. It produces estrogen.

PlacentaThe placenta anchors the developing fetus to the uterus and provides a bridge for the the exchange of nutrients and waste products between the mother and the developing baby.

TestesThe testes are the male reproductive glands. They control the development of secondary sex characteristics during adolescence. It produces testosterone.

Problems or AbnormalitiesEndocrine SystemSecretions of HormonesHyposecretionHypersecretionProduction of too little hormone by a diseased gland Production of too much hormone by a diseased gland

DiabetesDiabetes mellitus is a disease that may be caused by inadequate insulin production by the pancreas. Symptoms include: lack of energy weight loss extreme thirst frequent urination

THYROIDHYPOTHRYOIDISMHYPERTHYROIDISMUnderactive thyroid gland can cause a dull facial expression, hoarse voice, facial puffiness, coarse, dry skin and hair, and weight gain.Goiter- caused by low dietary iodine intakeCretinsim- when hyposecretion occurs in infants/toddlersOveractive thyroid gland produces symptoms that may include protrusion of eyeballs, warm, moist skin, trembling hands, nervousness, increased sweating, disturbed sleep, and weight loss.

Growth HormonehyposecretionhypersecretionDwarfisimGigantism

Acromegaly results when GH is secreted too much after adolescents.

ParathyroidParathyroid hormone (PTH) and vitamin D help manage calcium balance in the bodyCalcium is important to many body functions, including:Bone formationHormone releaseMuscle contractionNerve and brain functionParathyroid and Nerve Cells

ParathyroidhypersecretionhyposecretionResults in hypercalcemiaCauses several abdominal, muscle, kidney and psychological symptomsResults in hypocalcemiaSymptoms include:Petechiae (red spots on skin)Strong muscle contractions of the hand (cramping)Life threateningECG changes