Flashcards in For exam 2 lecture 1 Deck (37):
How does the Nervous System work?
Controls homeostasis through nerve impulses (action potentials) conducted along axons of neurons.
How does the Endocrine System work?
Releases its messenger molecules, called hormones into the bloodstream.
Together what does the Nervous and Endocrine systems do?
Coordinate functions of all body systems, maintain homeostasis.
The means of transferring information is called a?
The Nervous System causes what?
Muscles to contract and glands to secrete their product.
The Endocrine System alters what?
Metabolic activities, regulate growth and development, and guides reproductive processes.
Speed of Nervous System is ?
Which system is long term?
What is the Endocrine System made up of?
Endocrine Glands and scattered cells
Endocrine Glands are
Ductless and secrete hormones into extracellular spaces from which they enter the blood stream and circulate throughout the body to their target areas.
Specialized chemical substances produced and secreted by an endocrine cell or organ are?
T:F Hormones effect many target cells.
False: Effective only at specific target cells
How do hormones work
Influence their target cells by chemically binding to integral proteins or glycoprotein molecules called receptors
Integral proteins or glycoprotein molecules that hormones bind to are called?
What is the difference between Circulating Hormones and Local Hormones?
Circulating are dumped into the blood stream and act on distant target cells.
Local hormones act locally without first entering the blood stream.
Circulating hormones are called?
What are the two types of Local hormones?
Paracrines and Autocrines
What is the difference between Paracrines and Autocrines
Paracrines act on neighboring cells.
Autocrines act on the same cell that secreted them.
Chemical signal that is produced by neurons and function like hormones
Released by neurons at a synapse and influences a postsynaptic cell
A chemical signal secreted into the environment that modify the behavior of other individuals.
What are the 4 chemical classifications of hormones
Polypeptides and Proteins
Amine Hormones are?
Hormones derived from the amino acids tyrosine and tryptophan.
Hormones that consist of chains of amino acids are
Polypeptides and proteins and are synthesized on the rough endoplasmic reticulum and exported form the cell
Hormones from lipids derived from cholesterol
Hormones derived from arachidonic acid and exert control over many body systems
What is the difference between water-soluble hormones and steroid/thyroid hormones?
Water-Soluble circulate in watery plasma not attached to plasma proteins and find their receptors on the surface of the cell.
Steroid/thyroid hormones attach to specific transport proteins, which are synthesized by the liver. Steroid/thyroid hormones have to find their receptors inside the cell.
What are the three functions of transport proteins for hormones?
1) Improve transportability of lipid-soluble hormones by making them temporarily water-soluble
2) Slow the passage of small hormones through the filtering of the kidney (Slow hormones loss in the urine)
3) Provide a ready reserve of hormones already present in the blood stream
Mechanisms of hormone action:
Response to hormone depends on hormone and target cell
Various target cells respond differently to the same hormone
Often the response to a hormone is synthesis of new molecules
Transfer between blood and tissue only happen at the level of?
Why does the heart pump?
To get things into the capillary where transfer into the tissues.
Catecholamines, peptides, and proteins are?
Where and what are water-soluble hormone's receptors?
Integral proteins on the plasma membrane of target cells.
Since water-soluble hormones can only deliver their message to the plasma membrane they are called?
What is needed to relay the message inside the cell where hormone-stimulated responses can take place?
Hormone secretion control 3 ways:
1) Signals from the nervous system
2) Chemical changes in blood
3) Other hormones
A hormone is released in response to a specific stimulus and usually, its action reverses or negates the stimulus known as?
Negative feedback mechanism