Presentation on theme: "Ch. 40 Warm-Up What type of behavior in animals might be triggered by cold temperatures? What type of behaviors might be triggered in hot temperatures?"— Presentation transcript:
1Ch. 40 Warm-UpWhat type of behavior in animals might be triggered by cold temperatures?What type of behaviors might be triggered in hot temperatures?List 2 examples of negative feedback. List 2 examples of positive feedback.What is the main type of chemical messenger in the endocrine system? The nervous system?
2Warm-UpCompare and contrast the nervous system with the endocrine system. (Focus on the effects on the body)Define neurosecretory cell. What is its function?Give an example of positive and negative feedback in the endocrine system. How do they function?
3Ch. 45 Warm-Up Compare peptide hormones to steroids. Explain how insulin and glucagon work to regulate blood sugar levels.Which glands and hormones respond when your body is under stress?
4Chapter 45 Hormones and the Endocrine System A hormone called ecdysteroid regulates the timing of metamorphosis in this anise swallowtail butterfly.
5You must know: Two ways hormones affect target organs. The secretion, target, action, and regulation of at least 3 hormones.An illustration of both positive and negative feedback in the regulation of homeostasis by hormones.
7Endocrine System = Hormone-secreting cells + Tissues Endocrine glands: ductless, secrete hormones directly into body fluidsHormones: chemical signals that cause a response in target cells (receptor proteins for specific hormones)Affects 1 tissue, a few, or most tissues in bodyOr affect other endocrine glands (tropic hormones)Regulation by Positive & Negative Feedback
8Pheromones Hormones Local Regulators Chemical signal from 1 individual to another individualChemical signal from endocrine gland through blood to target cellChemical signal from one cell to an adjacent cellEg. ant trail; sex phermonesEg. peptide, steroid hormonesEg. cytokines, growth factors, nitric oxide (NO)
21Insulin & Glucagon: Control blood glucose levels
22Control of Blood Glucose High blood glucoseLiver breaks down glycogen and releases glucose into bloodInsulin released from pancreasBody cells take up glucoseLiver stores glucose as glycogenGlucagon released from pancreasBlood glucose drops
23Diabetes Mellitus Type I diabetes (10%):deficiency of insulin Insulin-dependentAutoimmune disorder beta cells of pancreas destroyedType II diabetes (90%): failure of target cells to respond to insulinNon-insulin dependentInsulin produced cells don’t respond (defect in insulin receptor or response pathway)Risk factors: obesity, lack of exercise
24Thyroid Gland Graves’ Disease: Autoimmune disorder HypothalamusTRHAnteriorpituitaryTSHThyroidT3T4Graves’ Disease:Autoimmune disorderAntibodies bind to TSH receptorHyperthyroidismHigh temp, sweating, weight loss, high BP
26Anabolic-Androgenic Steroid (AAS) Use Legally prescribed to treat hormone deficiency, loss of muscle mass (cancer, AIDS)Used to enhance performance and improve physical appearance
27Effects of AAS Abuse Source: www.drugabuse.gov/infofacts/steroids.html aggressionextreme mood swingsliver damagejaundicefluid retentionhigh blood pressureincreases in LDL (“bad” cholesterol)decreases in HDL (“good” cholesterol)renal failuresevere acneFor men—shrinking of the testicles, reduced sperm count, infertility, baldness, development of breasts, increased risk for prostate cancerFor women—growth of facial hair, male-pattern baldness, changes in or cessation of the menstrual cycle, enlargement of the clitoris, deepened voiceFor adolescents—stunted growth due to premature skeletal maturation and accelerated puberty changes; risk of not reaching expected height if AAS is taken before the typical adolescent growth spurtIn addition, people who inject AAS run the added risk of contracting or transmitting HIV/AIDS or hepatitis.