Module 1 Flashcards
(113 cards)
What are the main functions of the endocrine system?
Homeostasis, Storage and utilization of energy substrates, Growth, Development, Reproduction, Response to environmental stimuli
What is the response of the nervous system relative to the endocrine system?
The endocrine system has slower responses but prolonged and more diffuse and longer lasting
What are the primary organs of the endocrine system?
Hypothalamus, Pituitary gland, Thyroid Gland, Parathyroid Glands, Adrenal Glands, Pacreas, Gonads, Placenta, Hormones and hormone like substances are also produced in other organs.
Define Endocrine Gland
Ductless gland that secrete hormones into blood stream
Define Target Organs
The organ that contains cells with receptors that have hormone specific receptors
Define Hormone
chemical messengers released by one cell to communicate with others
T/F A single hormone can facilitate multiple effects on different target tissue?
T. Different receptors will mediate different responses.
T/F a single physiological function can not be regulated by the sum of multiple hormones
F. A single physiological function can be regulated by the sum of multiple hormones. ex. BP is influenced by ADH, aldosterone, epinephrine etc…
Define Endocrine signaling
Transmitters are released into the bloodstream
Define Paracrine signaling
Released by a cell but doesn’t go too far in the blood stream, talks to nearby tissue
Define Autocrine Signaling
Mechanism from cell to talk to itself
Define Intracrine signaling
Can be same as autocrine - but is also the cell talking to itself and never sending the message out.
What is the most common form of regulation in hormone secretion?
Negative feedback
Define negative feedback and provide an example
Hormone actions directly, or indirectly inhibit further release of hormone. Ex; Insulin released…blood glucose decrease..the decrease on blood glucose inhibits further insulin release
Which hormones are lipid soluble?
Steroid and thyroid hormones
Which hormones are water soluble?
Most hormones, GH, PTH etc (if water soluble they will need a transporter)
Where are hormone receptors located?
The cell membrane or within the cell itself
T/F Receptors are a fixed quantity, there is not much hormone receptor fluctuation allowing for more consistency.
F. Receptors are not fixed. There is continuous receptor turnover.
healthy receptors are adapting to make physiology _____efficient.
More efficient
unhealthy receptors are adapting to make phisiology _____ Efficient
Less
Define Up regulation
Any situation where the cell responds by either increasing the number or the sensitivity to the hormone. Either way the net result in an increased sesitivity.
Define Down Regulation
Cells start to adapt and the number of receptors or sensitivity of receptors is decreased. Net result is a decreased sensitivity to that hormone
What is the process of Primary messenger hormones in signal transduction
Primary messenger mechanism is for FAT Soluble Hormones. The hormone is the actual messenger to initiate intracellular response.
What is the process of secondary messenger hormones in signal transduction
Mechanism for Water soluble hormones. Hormone is first messenger which in-turn activates a secondary messenger inside the cell to initiate intracellular response