Endocrine System Introduction Quiz

Hormones act as chemical messengers that regulate physiological, metabolic, behavioral, and morphological effects on target cells.

Autocrine signaling involves a cell regulating itself, while paracrine signaling involves a cell releasing a substance to regulate neighboring cells.

Claude Bernard introduced the concept of internal secretion to describe substances released into the internal environment of the body.

<p>Endocrine secretion involves hormones being released into the bloodstream, while neurosecretion involves hormone release from certain neurons into the bloodstream.</p> Signup and view all the answers

<p>CCK can act as a hormone in the digestive tube and as a neurotransmitter in the central nervous system.</p> Signup and view all the answers

<p>The kidneys are involved in synthesizing calcitriol.</p> Signup and view all the answers

<p>This is known as endocrine signaling.</p> Signup and view all the answers

<p>Hormones are specifically stimulatory substances that act on target cells, unlike other substances that may not have such effects.</p> Signup and view all the answers

<p>Downregulation refers to the reduction of receptor density due to excess hormones, leading to decreased hormone binding and response.</p> Signup and view all the answers

<p>Receptor downregulation can occur through enhanced receptor degradation and decreased receptor synthesis.</p> Signup and view all the answers

<p>Upregulation refers to the increase in receptor density in response to a lack of hormones.</p> Signup and view all the answers

<p>The three types of hormone receptors are membrane receptors, cytoplasmic receptors, and nuclear receptors.</p> Signup and view all the answers

<p>Fat-soluble hormones enter the cell and bind to nuclear receptors, stimulating DNA transcription and protein synthesis.</p> Signup and view all the answers

<p>Second messengers activate intracellular signaling pathways after hormone-receptor interactions.</p> Signup and view all the answers

<p>Hormones such as ACTH, FSH, LH, TSH, MSH, Ang II, and ADH activate the cAMP system.</p> Signup and view all the answers

<p>ADH, acting on V1 receptors, activates the calcium-phosphoinositol system.</p> Signup and view all the answers

<p>Ca²+ binds to calmodulin and troponin C, generating activation of enzymes and promoting actin-myosin interaction.</p> Signup and view all the answers

<p>Hormones are primarily transported via the bloodstream, but also through lymph to a lesser extent.</p> Signup and view all the answers

<p>Peptidic hormones are water-soluble, while steroid hormones are fat-soluble.</p> Signup and view all the answers

<p>Peptide hormones are inactivated intracellularly by phagocytosis and hydrolysis by extracellular enzymes.</p> Signup and view all the answers

<p>The bound hormone form serves as a physiological storage that provides a gradual release of hormones according to bodily needs.</p> Signup and view all the answers

<p>Chronotropic control involves the rhythmical modulation of biological activity, influenced by either exogenous or endogenous biological clocks.</p> Signup and view all the answers

<p>Hormones are eliminated through metabolic inactivation and excretion in urine or bile.</p> Signup and view all the answers

<p>The mechanisms include chronotropic control, nervous control, feedback mechanism, receptor regulation, and activation/inactivation regulation.</p> Signup and view all the answers

<p>They synthesize and secrete releasing factors that stimulate pituitary hormone production and release.</p> Signup and view all the answers

<p>They secrete biogenic amines such as norepinephrine, dopamine, and serotonin, which control the secretion of hormones from parvicellular neurons.</p> Signup and view all the answers

<p>In an endocrine feedback system, the first hormone regulates the secretion of the second hormone, which in turn modulates the first hormone's secretion.</p> Signup and view all the answers

<p>Negative feedback is the most common type of feedback for regulating hormone levels.</p> Signup and view all the answers

<p>An example is the surge of LH that leads to ovulation, resulting in a continuous increase of estrogen until a peak is reached.</p> Signup and view all the answers

<p>Down-regulation refers to the decrease in the number of exposed receptors on target cells when hormone concentration rises.</p> Signup and view all the answers

<p>They explain how plasma compounds like calcium or glucose can regulate hormone secretion.</p> Signup and view all the answers

<p>High insulin concentration leads to full stimulation of recipient cells and can trigger down-regulation of insulin receptors.</p> Signup and view all the answers

<p>He claimed it enhanced his physical strength, improved intellectual capacity, and increased sexual potency.</p> Signup and view all the answers

<p>The leptin receptor activates multiple intracellular kinases such as JAK2, MAPK, and PI3K to induce specific cellular responses.</p> Signup and view all the answers

<p>They described the growth hormone.</p> Signup and view all the answers

<p>Insulin was discovered by Paulescu, followed by Banting and Best.</p> Signup and view all the answers

<p>Activation of Gs proteins stimulates adenylate cyclase, leading to an increase in cyclic AMP (cAMP) production.</p> Signup and view all the answers

<p>It helped improve the patient's condition by addressing the deficiency of thyroid hormones.</p> Signup and view all the answers

<p>Phosphodiesterase inhibits the synthesis of cAMP, thus reducing its intracellular concentration.</p> Signup and view all the answers

<p>Phospholipase C catalyzes the hydrolysis of phosphatidyl inositol 4,5-bisphosphate to produce IP3 and diacylglycerol.</p> Signup and view all the answers

<p>They discovered secretin and coined the term 'hormone' to describe chemical messengers.</p> Signup and view all the answers

<p>It established the vital role of parathyroid hormones in regulating calcium levels in the body.</p> Signup and view all the answers

<p>IP3 diffuses into the cytosol and binds to receptors on the sarcoplasmic reticulum, resulting in the opening of calcium channels.</p> Signup and view all the answers

<p>The effect of a hormone is determined by its coupling to either stimulatory G proteins (Gs) or inhibitory G proteins (Gi).</p> Signup and view all the answers

<p>Insulin treatment for diabetes and oral contraceptives for birth control.</p> Signup and view all the answers

<p>They treated it with posterior pituitary extracts.</p> Signup and view all the answers

<p>The final products are inositol triphosphate (IP3) and diacylglycerol (DAG).</p> Signup and view all the answers

<p>Calcium ions act as a secondary messenger that activates protein kinase C and regulates various cellular processes.</p> Signup and view all the answers