Aim: Endocrine System

FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS

Endocrine System releases hormones Hormones chemical messages from one body part to another part of body Functions: maintaining homeostasis energy production Growth & development reproduction

Responding to hormones Lock and key system hormone fits receptor on “target” cell target cell secreting cell non- target cells can’t read signal can’t read signal

Endocrine System GLANDS are what secrete the hormones into blood Pituitary Endocrine System Thyroid GLANDS are what secrete the hormones into blood chemicals cause slow, long-lasting changes in the body Adrenal Hormones coordinate slower but longer–acting responses to stimuli such as stress, dehydration, and low blood glucose levels. Hormones also regulate long–term developmental processes by informing different parts of the body how fast to grow or when to develop the characteristics that distinguish male from female or juvenile from adult. Hormone–secreting organs, called endocrine glands, are referred to as ductless glands because they secrete their chemical messengers directly into extracellular fluid. From there, the chemicals diffuse into the circulation. Pancreas Ovaries Testes

Glands Pituitary Thyroid Adrenal MASTER GLAND many hormones produced Controls the rate at which body uses energy Adrenal Releases adrenaline which helps the body respond to stress

Glands cont … Pancreas Ovary Testes Used in digestion Releases insulin to control amount of sugar in blood Ovary estrogen Testes testosterone

Body Regulation Hypothalamus “master nerve control center” Nervous & Endocrine system work together Hypothalamus “master nerve control center” Communicates with Pituitary gland “master gland” Releases many hormones hormones

Negative Feedback Response to changed body condition every time body is high or low from normal level a signal tells the body to make changes that will bring body back to normal level once body is back to normal level, signal is turned off hormone 1 lowers body condition gland high specific body condition

Controlling Body Temperature Nervous System Control Controlling Body Temperature nerve signals brain sweat dilates surface blood vessels high body temperature low constricts surface blood vessels shiver brain nerve signals

Regulation of Blood Sugar Endocrine System Control Regulation of Blood Sugar insulin body cells take up sugar from blood liver stores sugar reduces appetite pancreas liver high blood sugar level (90mg/100ml) low liver releases sugar triggers hunger pancreas liver glucagon