Presentation on theme: "The Endocrine System Are your hormones runnin’ wild?"— Presentation transcript:
The Endocrine System Are your hormones runnin’ wild?
Glands Exocrine - Secrete into ducts or onto a free surface - sweat, sebaceous, mucous, digestive Endocrine - secrete into cellular space then into blood - hormones
Hormones Hormones are chemical messages Regulate the chemical composition and volume of the internal environment What are some examples of regulation of chemical composition of blood. How about volume Glucose, Water Regulated by insulin and a hormone called ADH (antidiuretic hormone)
Hormones Help regulate organic metabolism and energy balance Thyroid gland Help body cope with emergency environmental demands - infection, trauma, emotional stress, dehydration, starvation, hemorrhage, and temperature extremes. Adrenaline (epinephrine) Fight or flight syndrome Sympathetic
Hormone producing cells are sent information from sensing and signaling systems - permit regulation of amount and duration of hormone release Examples: Blood glucose, Na+, K+, Ca++, O2
Target cells - cells that are affected by specific hormones Receptors - most cells have receptors that bind to one or more hormones There are about 50 different hormones - cells only respond to specific hormones Once a hormone binds to a cell’s receptors, there is a set of reactions within the target cell to produce the desired effects
Feedback Systems “Circular situation in which information about the status of something is continually reported (fed back) to a central control region.” Like a thermostat. Negative feedback system - reverses the direction of the initial condition Negative - response is opposite to the stimulus