LAB-ENDOCRINE SYSTEM


T/F.The ENDOCRINE SYSTEM regulates the function of every cell, tissue and organ in the body.
True False


TRUE.*Acts to maintain a stable internal body environment, REGARDLESS of changes OCCURING within or outside of the body.*ENDOCRINE cells have the ability to sense and respond to changes via the excretion of specific chemicals known as HORMONES.


T/F. Hormones are carried in the blood usually attached to a specific plasma protein and circulate around the body.
True False


TRUE.*When a hormone-protein complex reaches a TARGET CELL, the hormone detaches from the PROTEIN and enters the cell to induce a specific reaction.


Hormones that are composed of CHAINS of AMINO ACIDS, work by first attaching to a protein receptor in the cell membrane?


POLYPEPTIDE HORMONE-Initiating a series of reactions IN THE MEMBRANE resulting in CYCLIC ADENOSINE MONOPHOSPHATE (cAMP) entering the cell.*The entrance of this chemical into cell induces the cell to work harder and faster.


They are hormones secreted by the THYROID?


STEROID HORMONES and THYROXINE-*They enter the cell to attach to a CYTOPLASMIC RECEPTOR. The hormone-receptor complex then enters the NUCLEUS of the cell to attach to specific POINTS in the DNA. Each attachment causes the production of a specific mRNA, which then moves to the cytoplasm to be translated into a specific protein.


T/F. Most regulation of hormone levels in the body is conducted by negative feedback.
True False


TRUE*If a particular hormone is needed, production of that hormone will be stimulated.*If there is enough of a particular hormone present, production of that hormone will be inhibited.