endocrine system pp 1031-1042
DESCRIPTION
ENDOCRINE SYSTEM pp 1031-1042 . Warm-up 4/15: Describe the function of the Endocrine System. What tissues/ organs are part of the endocrine system? . FUNCTION. Controls body function with chemical messengers Hormones: chemical messengers Glands: secrete chemicals/hormones . HORMONES. - PowerPoint PPT PresentationTRANSCRIPT
ENDOCRINE SYSTEMpp 1031-1042
Warm-up 4/15: a. Describe the function of the
Endocrine System.b. What tissues/ organs are part of
the endocrine system?
FUNCTION
• Controls body function with chemical messengers
• Hormones: chemical messengers• Glands: secrete chemicals/hormones
HORMONES
• Amino acid-based hormones: first messenger binds to cell surface receptor causing second messenger inside the cell to initiate cell activity
• Steroid hormones: diffuse through cell membrane to bind to a protein which starts transcription
GLANDS• exocrine: secrete nonhormonal chemicals
through ducts (sweat, saliva, mucous, digestive, etc)
• endocrine: secrete hormones into the bloodstream a. gonads: sex hormones b. thyroid: metabolism c. adrenal gland: adrenaline d. pituitary: hormones that affect other glands and growth hormones e. pancreas: insulin and glucagons to regulate sugar f. thymus: stimulates formation of T-cells
FEEDBACK MECHANISMS
• Homeostasis: stable internal environment• Last step of the series controls the first
NEGATIVE FEEDBACK
• A secondary substance inhibits production of the initial stimulating substance
A = InsulinB = glucagon (sugar)
Negative feedback loops are necessary for homeostasis.
Negative Feedback Loop
Holding breath, CO2 levels rise,
Control system forces exhale, inhale
O2 / CO2 level returns to normal
POSITIVE FEEDBACK
• A secondary substance stimulates production of the initial stimulating substance
Birth
HW
• Worksheet: Nervous and Sense Organs (Due Tuesday)
• Trifold Vocab: homeostasis, neuron, gland, hormone, positive feedback loop, negative feedback loop, synapse, neurotransmitter (Due Wednesday)