Endocrine System Flashcards
What is the function of the endocrine system?
Controls, monitors organs, glands, and processes int the body using hormones.
Anatomy of the Endocrine System
organs and small glands are mostly disconnected, not at all like organs in other systems
What are some organs that are apart of the endocrine system and nervous system?
hypothalamus, pituitary gland, adrenal glands, and pineal gland
Endocrine glands:
Are ductless glands that secrete hormones directly into the bloodstream
Exocrine glands (not part of this system):
Are sweat, and salivary glands that go through a duct to a “surface”
HORMONES:
= chemical messengers that influence the activities of tissues and organs
STERIOD hormones:
=lipid (fat) based, receptors found inside the nucleus (activates mRNA production and stimulates protein synthesis)
NON-STERIODAL hormones:
protein (peptide) or amino acid derived, have receptors on the cell membrane surface (activate secondary messages that work inside the cell)
Where are hormones transported to?
Hormones are transported all around the body to TARGET cells, that have specific RECEPTORS
Binding of hormone to specific target cell influences the cell’s activity:
-changes the cell’s membrane permeability
-increases or decreases enzyme activity
-increases protein synthesis
-stimulates secretion
What are the major endocrine organs?
The hypothalamus, pineal gland, pituitary gland, thyroid gland, thymus gland, adrenal glands, + the male testis and female ovaries.
the hypothalamus:
-part of both nervous and endocrine system (small/deep in brain) (connects nervous system to endocrine system)
- collects info from body system and integrates responses to maintain homeostasis
-has control over pituitary
What does the hypothalamus regulate?
metabolism, heart rate, energy level, body temperature, thirst, nutrient intake, blood pressure, blood composition, sometimes even emotions, and regulating sleep.
Where are adrenal glands located?
On top of the kidneys, pyramid shaped
Adrenal Cortex:
-outer layer of the gland
-secretes cortisol (stress hormone)increases blood glucose levels
Adrenal Medulla:
-inside of the gland
-secretes epinephrine (adrenaline) and norepinephrine (noradrenaline) in physical + emotional stress
An adrenaline rush creates the…
blood flow to be shunted/pushed into the muscles and energy becomes more available (increases heart rate, and blood pressure +breathing)
What are reproductive glands called?
Gonads
Ovaries:
-produce eggs for reproduction
- produce estrogen and progesterone to help develop female sex characteristics, and to regulate the menstrual/period cycle
Testes:
-produce sperm for reproduction
- androgen and testosterone hormones/regulate sperm production and develop male sex characteristics
Where is the thymus located?
under sternum, anterior to the heart
Thymus:
-roles in lymphatic and immune system
- releases hormone thymosin
Where is the pineal gland located?
In the brain
Pineal gland:
-role in sleep
-releases melatonin for sleeping
The pituitary gland phenotype..
Pea-sized, bi-lobed gland (two lobes), located at the base of the brain
Pituitary gland:
-most hormones secreted by the pituitary gland stimulate other endocrine glands
-“master gland” of endocrine gland
Pituitary hormone: GH
-Growth Hormone -acts directly on body tissues
-responsible for growth and development of muscles, cartilage, and bones
-even changes metabolism to use fat +protein for energy in excessive physical activity
Pituitary Hormone: Adrenocorticotropin (ACTH)-
stimulates adrenal glands
Pituitary Hormone: Thyroid-stimulating hormone (TSH)
stimulates thyroid gland
Pituitary Hormone: Oxytocin
(from hypothalamus- posterior end of pituitary releases)
-Roles in birth and breastfeeding
- “Love” hormone
Where is the thyroid gland located?
Inferior to the larynx, at the base of the throat
Thyroid Gland:
(voice box, Adam’s apple)
-butterfly shaped
-roles in growth, development, maturation, (energy production)
What does the thyroid gland secrete?
-Thyroxine (t4) and Triiodothyronine (t3)
(Thyroid is controlled by TSH from pituitary)
Where is the pancreas located/resembles?
A long thin gland located posterior to stomach
Pancreas:
-both endocrine and exocrine
-endocrine: secretes hormones that control blood glucose levels
-Exocrine = digestive enzymes
Insulin:
-decreases blood sugar
- helps move sugar into cells
Glucagon
- increases blood sugar
-releases STORED sugars into the blood stream
The endocrine system…
sends hormones through circulatory system
HORMONES REGULATE
-breakdown of chemical substances in metabolism of what we ingest
-fluid balance/urine production
-body’s growth+development
-sexual reproduction
