Please enable JavaScript.
Coggle requires JavaScript to display documents.
Endocrine System by Miabella Aguilar & Period. 5 - Coggle Diagram
Endocrine System by Miabella Aguilar & Period. 5
1. Major functions of the endocrine system
Endocrine system controls and integrates:
Reproduction
Growth & Development
Maintenance of electrolyte, water, and nutrient balance of blood
Regulation of cellular metabolism and energy balance
Mobilization of body defenses
Endocrine System:
acts with nervous system to coordinate and integrate activity of body cells
Influences metabolic activities via hormones transported in blood
Responses slower but longer lasting than nervous system response
2. Major endocrine glands/organs and their functions (separate by region/ body cavity)
• Include the hormones produced, their functions and their target organs
Thoracic Cavity
Parathyroid glands:
Stimulates osteoclasts digest bone matrix & release Ca2+ in blood.
Enhances reabsorption of Ca2+ and secretion of phosphate (PO43-) by kidney's
Promotes activation of vitamin D by kidneys, which leads to increased absorption of Ca2+
Hormones: Parathyroid hormone (PTH) or parathormone
Target organ: Bone and Kidneys
Thymus:
Produces and matures lymphocytes or immune cells
Hormones: Thymosin, thymopoietin, and thymulin
Target organ: Growth hormone (GH)
Thyroid gland:
Produces and releases certain hormones.
Hormones: Thyroxine and Triiodothyronine
Target organ: the heart, CNS, ANS, bone, and metabolism
Abdominal Cavity
Adrenal glands:
- Paired, pyramid-shaped Organs atop kidneys
Adrenal Cortex:
3 layers of glandular tissue that synthesize and secrete several different hormones
Hormone: corticosteroids; mineralocorticoidoids, Glucocorticoids, Gonadocorticoids
steroid hormones are not stored in cells and 3 layers of cortical cells produce 3 different corticosteroids
Adrenal Medulla:
Nervous tissue that is part of sympathetic nervous system
Hormones: Epinephrine & norepinephrine
vasoconstriction
increased heart rate
increased blood glucose levels
blood diverted to brain, heart, and skeletal muscles
Pancreas:
Triangular gland located partially behind stomach
Hormones: Alpha cells - glucagon & Beta cells insulin
Cranial Cavity
Hypothalamus:
Is a neuroendocrine organ. Secretes hormones that stimulate or suppress the release of hormones in the pituitary gland
Target Organs: Pituitary, thyroid, adrenal glands, kidneys, and reproductive system
Pituitary gland:
Regulates growth, metabolism, and reproduction through hormones.
Hormones produced are GH, TSH, ACTH, FSH, LH, PRL, and MSH
Target organs: Adrenal gland, gonads, or thyroid gland
Pineal gland:
Function: Receives information regarding the light-dark cycles for sleep in order to produce the hormone
Melatonin
Target Organ: targets hypothalamus and pancreas
Pelvic Cavity
Gonads:
gonads produce same steroid sex horror moans as those of adrenal cortex, just lesser amounts
ovaries produce estrogen and progesterone
estrogen: maturation of reproductive organs, appearance of secondary sex characteristics, with progesterone causes breast development and cyclic changes in the uterine mucosa
testes produce testosterone
testosterones: initiates maturation of male reproductive organs, causes appearance of male secondary sex characteristics and sex drive, necessary for normal sperm production, maintains reproductive organs in functional state
3. Compare and contrast steroid vs. non-steroid hormones and list the hormones for each
category
Steroid Hormone
- amino acid-based hormones:
amino acid deivatives, peptides, and proteins
water-soluble
Steroids:
synthesized from cholesterol
gonadal and adrenocortical horomes
lipid-soluble
Parathyroid hormone:
PTH is most important hormone in Ca2+ homeostasis
secreted in response to low blood levels Ca2+
inhibited by rising levels of Ca2+
Functions:
stimulate osteoclasts digest bone matrix and Ca2+ in blood
enhances reabsorption Ca2+ and secretion of phosphate by kidneys
promote activation of vitamin D by kidneys which leads to increase absorption of Ca2+
Mineralocorticoids:
regulates electrolyte concentrations
Aldosterone: most potent mineralocorticoid
-stimulates Na+ reabsorption by kidneys
-results in increased blood volume and blood pressure
-stimulates k+ elimination by kidneys
Thyroxine & Triiodothyronine:
Body's major metabolic hormone and found in both forms
both are iodine containing amine hormones
TH affects virtually every cell in body
enters target sell in binds to intracellular receptor within nucleus
triggers transcription of various metabolic genes
Glucocorticoids:
influence Metabolism of most cells and helps resist stressors
keep blood glucose levels relatively constant
maintain blood pressure by increasing the action of vasoconstrictions
Prolactin:
Stimulated by decreased PIH release enhanced by estrogens, birth control pills, breast-feeding, and dopamine blocking drugs. Inhibited by PIH
-Target organ: Breast secretary tissue
Gonadocorticoids:
weak androgens converted to testosterone and tissue cells, some to estrogens
many contribute to:
-onset of puberty in appearance of secondary sex characteristics
-Sex drive in women
-source of estrogen in postmenopausal women
Luteinizing hormone:
Stimulated by GnRH & Inhibited by feedback inhibtion exerted by estrogen and progesterone in females and testosterone in males
Target organ: ovaries in Testes
Epinephrine & Norephrine:
Effects of catecholamine:
Vasoconstriction
increased heart rate
increase blood glucose levels
blood diverted to brain, heart, and skeletal muscles
both hormones have basically same affects but:
-Epinephrine is more a stimulator of metabolic activities
-Norepinephrine has more of an influence on peripheral vasoconstriction and blood pressure
Follicle stimulating hormone:
stimulated by GnRH & inhibited by feedback inhibition exerted by inhibin, and estrogens and female and testosterone in males
Target organ: Ovaries and Testes
Estrogen & Progesterone:
gonads produce same steroid sex hormones as those of adrenal cortex, just lesser amounts
ovaries produce estrogen and progesterone
Estrogen:
-maturation of reproductive organs
-appearance of secondary sex characteristics
-which progesterone, causes breast development and cyclic changes in uterine mucosa
Adrenocorticotropic hormone:
Stimulated by CRH, stimuli that increase CRH release include fever, hypoglycemia, and other stressors. Inhibited by feedback inhibition exerted by glucocorticoids.
Targe organ: Adrenal cortex
Testosterone:
testes produce testosterone
initiates maturation of male reproductive organs
causes appearance of male secondary sex characteristics and sex drive
necessary for normal sperm production
-maintains reproductive organs in the functional state
Thyroid- stimulating hormone:
Stimulated by TRH & in infants indirectly by cold temperatures. Inhibited feedback inhibition exerted by thyroid hormones on anterior pituitary and hypothalamus and by GHIH.
Target organs: Thyroid gland
Melatonin:
melatonin affects:
timing of sexual maturation of puberty
day/night cycles
psychological processes that show rhythmic variations
production of antioxidant and detoxification molecules in cells
Non-Steroid hormone
Glucagon:
extremely potent
-triggered by decrease blood glucose levels, rising amino acid levels, or sympathetic nervous system
-raises blood glucose levels by targeting liver to:
-Break down glycogen into glucose
-synthesize glucose from lactic acid and other non-carbohydrates
-release glucose into the blood
*Insulin:
secreted warm blood glucose level increase
insulin lowers blood glucose levels in three ways:
-enhances membrane transport of glucose into fat and muscle cells
-inhibits breakdown of glycogen to glucose
-inhibits conversion of amino acids are fats to glucose
5. Diseases associated with the endocrine system
Hypersecretion - cushing's syndrome/disease:
depressed cartilage/bone formation and immune system; inhibits inflammation; disrupts neutral, cardiovascular, and gastrointestinal function
causes colon tumor on pituitary, lungs, pancreas, kidney, or adrenal cortex; overuse of corticosteroids
cushingoid signs: "Moon" face or "buffalo hump"
treatment: removal of tumor discontinuation of drugs
Hyposecretion - Addison's disease:
usually involved defecates in both glucocorticoids and mineralocorticoids
decrease in plasma glucose in Na+ levels
Weight loss, severe dehydration and hypotension are common
treatment: Corticosteroid replacement therapy
Early sign is characteristics bronzing of skin due to high levels of ACTH which triggers melatonin production in melanocytes
Hypersecretion:
most common type of Graves' disease
auto immune disease: body makes abnormal antibodies directed against thyroid follicular cells
symptoms include elevated metabolic rate, sweating, rapid and irregular heartbeats, nervousness, and weight loss despite adequate food
treatments include surgical removal of thyroid or radioactive iodine to destroy active thyroid cells
Diabetes mellitus (DM):
can be due to:
hyper secretion of insulin: type one
hypo activity of insulin: type two
Three cardinal signs of DM:
-
Polyuria:
huge urine output
glucose acts as osmotic diuretic
Polydipsia:
excessive thirst
from water loss due to polyuria
Polyphagia:
excessive hunger and food consumption
cells cannot take up glucose and are "Starving"
Hyposecretion
: hyposecretion of TH in adults can lead to myxedema
symptoms include low metabolic rate, thick and or dry skin, puffy eyes, feeling chilled, constipation, edema, mental sluggishness, and lethargy
If due to lack of iodine a goiter may develop
lack of iodine decreases TH levels, which triggers increase TSH secretion, triggering thyroid to synthesize thyroglobulin
TH is critical for normal growth and brain development in early childhood
congenital hypothyroidism is usually caused by poor development of thyroid gland
Ketones:
when sugars cannot be used as fuel, as in DM, fats are used causing lipidema: high levels of fatty acids in blood
fatty acids metabolism results information of ketones
ketones are acidic and they're build up in blood can cause ketoacidosis
also causesketonuria: ketone bodies in urine
Hypersecretion of Growth hormone:
hypersecretion of GH is usually caused by anterior pituitary
in children results in gigantism
can reach heights of 8 feet
in adult acromegaly
overgrowth of hands, feet, and face
hyposecretion of GH
in children results in pituitary dwarfism
mini reach heights of only 4 feet
in adults usually causes no problems
Hyperinsulinism:
excessive insulin secretion
causes hypoglycemia: low blood glucose levels
symptoms: activity, nervousness, disorientation, unconsciousness, even death
Treatment: sugar ingestion
Diabetes insipidus:
ADH deficiency due to damage to hypothalamus or posterior pituitary
Must keep well hydrated
4. Homeostatic mechanisms of hormone regulation (negative and positive feedback)
Positive feedback:
Oxytocin and ADH
-each composed of nine amino acids
-almost identical but different into amino acids
Oxytocin:
-strong stimulant of uterine contractions released during childbirth
-also access hormonal trigger for milk ejection
-both are
positive feedback mechanisms
-act as Neuro transmitter in brain
Hormones are released to initiate actions that lead to an additional release of that hormone
Negative feedback:
Hormone release
blood levels of hormones
-controlled by negative feedback systems
-increased hormone effects on target organs can exhibit further hormone release
-levels vary only within narrow, desirable range
-hormone release is triggered by:
Endocrine Gland stimuli
Nervous System Modulation