+ The Endocrine System

+ Functions To control many of the body’s daily activities Controls the body’s long term changes such as development

+ Structures Endocrine glands – organs that produce and release chemicals directly into the bloodstream Hormones – the chemicals released by Endocrine glands; can be thought of as chemical messengers

+ Hormones Act as internal stimuli that direct the body’s response Hormones only interact with certain target cells – cells that recognize the hormone

+ Hormone Production 1.Nerve impulses from your senses travel to the brain 2.Sound of thunder is interpreted 3.Brain sends nerve impulses to a specific endocrine gland 4.That gland releases the hormone, adrenaline, into the bloodstream 5.Adrenaline causes… 1.Increased heart rate 2.Breathe faster and deeper 3.Release sugar to your muscles In a Sudden Storm…

+ Hormone Production Hormones cause a slower, but longer-lasting response When adrenaline reaches the heart, it pumps faster and will continue to do so until the amount of adrenaline goes back to normal

+ Structures & Functions The Hypothalamus Found in your brain (near the middle of your head) Responsible for – controlling sleep, hunger, and other endocrine glands and organs

+ Structures & Functions The Pituitary Gland Found below the hypothalamus Responsible for – regulating body processes like growth, blood pressure, and water balance, and helps control other endocrine glands

+ Structures & Functions The Thyroid Gland Found at your neck Responsible for – controlling the release of energy from food molecules

+ Structures & Functions The Parathyroid Gland Found at your neck Responsible for – regulating the amount of calcium in the blood

+ Structures & Functions The Thymus Found at your chest Responsible for – helping cells in your immune system develop

+ Structures & Functions The Adrenal Glands Found on top of kidneys Responsible for – controlling the water/salt balance in the kidneys, the amount of sugar in the blood, and releasing adrenaline… in response to emergency situations

+ Structures & Functions The Pancreas Found in front of kidneys Responsible for – produces the hormones, insulin and glucagon, to control the level of sugar in the blood

+ Structures & Functions The Ovaries Responsible for – produces the female sex hormones Estrogen controls the changes in a teenage girl’s body Estrogen and Progesterone trigger the development of eggs

+ Structures & Functions The Testes Responsible for – produces the male sex hormones Testosterone controls the changes in a teenage boy’s body and needed for normal sperm production

+ Hormones controls the body’s response in many different situations… In exciting situations, like roller coasters As a child grows older

+ Use of Negative Feedback Temperature is above 78° F Temperature is at 78° F START STOP The thermostat signals the air conditioner to turn on The thermostat signals the air conditioner to turn off Negative Feedback is an important way that the body maintains stable internal conditions, or homeostasis.

+ Use of Negative Feedback Blood sugar level of 170 Blood sugar level at 95 START STOP The pancreas is signaled to release insulin The pancreas is signaled to stop releasing insulin

+ The Endocrine System