Lecture: Endocrine System Flashcards
Define paracrine communication and the chemical involved
Messaging between cells through paracrines within a single tissue
Define Autocrine communication and the chemical involved
When chemical messages (autocrines) are received by the same cells that sent them
Prostoglandins are examples of what?
Autocrines
__1__ communication occurs when the endocrine system uses chemical messengers called __2__ to relay information between cells via the __3__.
Endocrine Communication
Hormones
Bloodstream
Specific cells that bind and receive hormonal messages
Target cells
How do hormones alter the operations of their target cells?
By altering the quantity or type of enzymes or structural proteins in target cells.
How do hormones alter the target cells themselves? (2)
By altering the biochemical properties or physical structure.
Define synaptic communication
Neurons release a neurotransmitter through a synapse close to target cells with appropriate receptors.
What allows the messages of the nervous system to travel so quickly?
Because action potentials travel through axons, a physical pathway;.
Through what medium does paracrine communication take place?
Extracellular fluid
Through what medium does autocrine communication take place?
Extracellular fluid
Through what medium does direct communication take place?
Gap Junctions
Through what medium does synaptic communication take place?
Across synapses
What are the chemical mediators of direct communication?
Ions, small solutes and lipid soluble materials.
Compared to the endocrine system, commands from the nervous system are __1__ and __2__?
Specific
Short lived
What 4 things do the nervous and endocrine system have in common?
Release chemicals that bind to specific receptors
Share some chemical receptors
Regulated by negative feedback mechanisms
Preserve homeostasis
What are the 5 main processes affected by hormones? (5)
Growth Reproductive capability Cell metabolism and energy balance Fluid and nutrient balance Mobilize body defenses
What are endocrine cells? Where do they release fluids?
Glandular secretory cells that release secretions into extracellular fluid
How are exocrine cells different from endocrine cells?
They release secretions onto epithelial surfaces by way of ducts
What are the 3 classes of hormones?
Amino Acid derivatives
Peptide hormones
Lipid derivatives
What is another word for an amino acid derivative?
Biogenic amines
Amino Acid derivatives are synthesized from the __1__, __2___ and __3__.
Amino acids
Tyrosine
Tryptophan
What hormones are made from tyrosine? (4)
Thyroid hormones
Epinephrine
Norepinephrine
Dopamine
What are Catechelomines?
Epinephrine
Norepinephrine
Dopamine