Endocrine System Flashcards
within the human body involves the transmission of signals to control and coordinate actions in an effort to maintain homeostasis.
communication
Communication within the human body involves the transmission of signals to control and coordinate actions in an effort to maintain
homeostasis
Two major organ systems are responsible for providing these communication pathways;
the nervous and endocrine systems
are sent viathe generation and propagation of action potentials which move along the membrane of a cell.
electrical signals
Once the action potential reaches the synaptic terminal;
the electrical signal is converted to a chemical signalas neurotransmitters are released into the synaptic cleft
When neurotransmittersbind with receptors on the receiving (post-synaptic) cell;
new electrical signal is generated and quickly continues to its destination
enables body functions that involve quick, brief actions, such as movement, sensation, and cognition
neural communication
primarily responsible for rapid communication throughout the body
nervous system
relies on only a single method of communication: chemical signaling
endocrine system
are the chemicals released byendocrine cells that regulateother cells in the body
hormones
are transported primarily via the bloodstream throughout the body, where they bind to receptors on target cells, triggering a response
hormones
chemical signal that elicits a response in the same cell that secreted it
autocrine
tissue or organ that secretes hormones into the blood and lymph without ducts such that they may be transported to organs distant from the site of secretion
endocrine gland
cells, tissues, and organs that secrete hormones as a primary or secondary function and play an integral role in normal bodily processes
endocrine system
cells, tissues, and organs that secrete substances directly to target tissues via glandular ducts
exocrine system
secretion of an endocrine organ that travels via the bloodstream or lymphatics to induce a response in target cells or tissues in another part of the body
hormone
chemical signal that elicits a response in neighboring cells; also called paracrine factor
paracrine system
involved in the information business.
endocrine system
carry essential messages that have far-reaching effects
hormones
control body processes at every level, from the energy uptake of a single cell to the whole body’s rate of growth and development.
endocrine system
sends hormones through the Circulatory system to control and coordinate body functions in much the same way as the nervous system uses tiny electrical signals
endocrine system
work together to integrate into the brain and complement each other, but they tend to work at different speeds.
endocrine and nervous system
respond within split-seconds but their action soon fades
nerves
Hormones regulate processes such as:
a. The breakdown of chemical substances in the metabolism of what we eat and drink
b. Fluid balance and urine production
c. The body’s growth and development
d. Sexual Reproduction
connects the nervous system to the endocrine system. It receives and processes signals from other brain regions and pathways and translates them into hormones, the chemical messengers of the endocrine system.
hypothalamus
released by the pituitary gland and the hypothalamus control the other endocrine glands and regulate all major internal functions
hormones
are a mixture of both endocrine (ductless, hormones are secreted into the blood) and exocrine (have ducts, hormones are secreted onto surfaces) glands
glandular tissue
examples of exocrine glands are:
sebaceous and sweat glands (in the skin), salivary glands (oral), Brunner’s glands.
This gland secretes thin watery secretions, which are rich in enzymes and antibodies, and the ducts open onto the surface of the oral mucosa
exocrine glands
do not have ducts. Their secretions (hormones) are secreted into the bloodstream.
endocrine glands
it is somewhat analogous to the coordinating activity of neurons
neuroendocrine
Some short-range endocrine activity also occurs in the digestive system
paracrine activity
released - hormones, are usually released by exocytosis, by the secretory cells, into the interstitial spaces and pass through fenestrated capillaries to enter the bloodstream and move to target organs.
signaling molecules
always found in close proximity to a capillary bed and have a rich network of blood vessels.
secretory cells of endocrine glands
The signaling molecules released - hormones, are usually released by
exocytosis
these include the pituitary (hypophysis), thyroid, parathyroid, adrenal, and pineal glands.
discrete endocrine glands
These include the kidney, pancreas, and gonads.
Endocrine component of Glands with both an Endocrine and an Exocrine Function
a small gland 6-8mm long is found in the brain, close to the hypothalamus, and is a photoreceptor organ, which is stimulated by information received via the retina, that secretes the hormone melatonin, which appears to regulate the circadian rhythms of the body
pineal gland
Also known as the hypophysis has a complex microanatomy and physical and functional interconnection with the hypothalamus.
pituitary gland
is a “master regulator” of sorts, playing essential roles in body homeostasis, including temperature regulation, behavior (including thirst, hunger, and sex), inherent body rhythms, and control of the pituitary gland which, in turn, bears an immense effect on endocrine organs elsewhere.
hypothalamus
hypothalamus is a “master regulator” of sorts, playing essential roles in body homeostasis, including
temperature regulation, behavior (including thirst, hunger, and sex), inherent body rhythms, and control of the pituitary gland
The pituitary gland is generally divided into two components with developmental and functional differences;
the anterior pituitary (adenohypophysis)and theposterior pituitary (neurohypophysis)
formed from adowngrowthof the diencephalon that forms the floor of the third ventricle.
posterior part
derived from anupgrowthfrom theoral ectodermof the primitive oral cavity calledRathke’s pouch.
anterior part
anterior pituitary (adenohypophysis) is composed of two histologically and functionally distinct regions;
the pars distalis and the pars intermedia.