Phys II - Intro to Endocrine Flashcards
What are the 2 systems that regulate the body’s internal enviornment?
- Nervous System
- Endocrine System
Of the 2 systems that regulate the body, which if RAPID?
Nervous System
Of the 2 systems that regulate the body which is involved in LONG TERM PROJECTS?
Endocrine System
Chemical Messenger: Neural
Nerotransmitters relased at synaptic junctions
RAPID response
Chemical messenger: Endocrine
Hormones relased from glands/cells
Hormones reach the circulating blood and influence the function of target cells some distance away
Neuroendocrine invovles?
Secretion products from nerons (neurohormones)
they reach the circulating blood and influence function of traget cells some distance away
Chemical messenger: PARACRINE
Cell secretion products diffuse into extracellular fluid
Affects NEIGHBORING target cells
(PARA - next to)
AUTOCRINE
Cell secretion products
Affect functions of the SAME cell by binding to surface receptors
(AUTO - self)
Chemical messenger: Cytokine
Secreted cell proteins
Function as:
- paracrines
- autocrines
- enocrines
They act on a broad spectrum of target cells
Hormones
Greek meaning - To arouse or excite
chemical messengers speeding from cell to cell along the blood stream my coordinate activities/growth of different parts of the body
What type of organs are involved in the edocrine system?
Organs whose primary functions is hormone production/release
there are other organs that secrete hormomes but it’s not their primary function
What does the endocrine system try to maintian in homeostasis?
- Growth
- Development
- Reproduction
- Blood pressure
- Water & Electrolyte balance
- Behavior
“Long term projects”
Major endocrine glands
- Pineal gland
- Pituitary gland
- Thyroid gland
- Parathyroid gland
- Thymus gland
- Pancreas
- Adrenal gland
- Ovaries/Testes
Hormones
Chemical messengers with regulatory effects on cells/organs
When endocrine glads secrete hormones, where are they released?
directly into TISSUE FLUIDS
NOT through ducts
“systemic effect” vs. “target tissue”
Target Tissue
Specific tissue the hormones act on
within the plasma membrane, cytoplasm or nuclues on target tissues where hormones bind
Receptor
Cell with in the target tissue. Must have appropriate protein receptor for specific hormones to bind to them
What happens when a protein hormone is bound to a target cell receptor?
Charateristic biological changes within the target cells
“A change in cell behavior”
What are the 3 classifications of hormones?
- Proteins/Peptides
- Steriod
- Amines
Protein/Peptide Hormones
Protein - 200 amino acids long
Peptide - as small as 3 aminio acids
Steroid Hormones
Derivative of cholesterol
Amines
Derivatives of tyrosine
Hormones from the thyroid gland (thyroxine, triiodothyronine)
Hormones from the adrenal medulla (epinephrine, norepinephrine)
What is the name for a hormome that is synthesized as inactive and is only activeated before or after release?
Prohormone
Which classification of hormone is the predominat hormone of the body?
Protein/Peptide Hormones
Which classification of hormone is water-soluble?
Protein/Peptide Hormones
Which classification of hormone is stored in endocrine cells until needed?
Protein/Peptide Hormone
Which classification of hormone acts as a second messenger, activates enzymes and it’s function is for CELL ACTIVITY AND METABOLISM?
Protein Hormones
Which classification of hormone is fat lipid base and can move easily through a membrane?
Steroid Hormone
Which classification of hormone is hydrophobic and Lipophilic?
Steroid Hormone
Which classification of hormone is NOT stored in a cell and travels to it’s target cells via a special carrier protein?
Steriod hormone
What is the “path” of a protein hormone?
protein hormone synthesized —>
stored in an endocrine cell inactive until needed —>
once needed the hormone binds to a target cell receptor on/in the cell membrane —>
hormone activates membrane enzyme —>
Stimulation of that enzyme results in synthesis of the second messenger —>
target enzymes within the cell will be activated and will run cellular processes (change cell behavior)
What is the “path” of a steriod hormone?
Steriod hormone synthesized —>
Hormone travels to a target cell attached to a carrie protein (rember they’re hydrophobic and don’t like water) —>
Hormone will pass through the cell membrane of the target cell ->
Hormones bind to receptors/genes inside the cell (cytoplasm or nucleus) —>
Hormones will switch on genes —>
Genes will synthesize proteins (CELL IS MAKING PROTEINS)
What is the term for the response on an endocrine gland that secretes a hormone and the response will change the rate of secretion of that hormone?
Feedback mechanisms
