1. 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?
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?

2. Warm-Up
Compare 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?

3. Ch. 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?

4. Chapter 45 Hormones and the Endocrine System
A hormone called ecdysteroid regulates the timing of metamorphosis in this anise swallowtail butterfly.

5. You 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.

6. Types of Intercellular Signaling

7. Endocrine System = Hormone-secreting cells + Tissues
Endocrine glands: ductless, secrete hormones directly into body fluids
Hormones: chemical signals that cause a response in target cells (receptor proteins for specific hormones)
Affects 1 tissue, a few, or most tissues in body
Or affect other endocrine glands (tropic hormones)
Regulation by Positive & Negative Feedback

8. Pheromones Hormones Local Regulators
Chemical signal from 1 individual to another individual
Chemical signal from endocrine gland through blood to target cell
Chemical signal from one cell to an adjacent cell
Eg. ant trail; sex phermones
Eg. peptide, steroid hormones
Eg. cytokines, growth factors, nitric oxide (NO)

10. Types of Hormones Peptide Steroid Water-soluble
Bind to receptors on plasma membrane & triggers signal transduction pathway
Affects protein activity already present in cell
Rapid response
Short-lived
Eg. oxytocin, insulin, epinephrine
Lipid-soluble
Enters cell & binds to intracellular receptors
Causes change in gene expression (protein synthesis)
Slower response
Longer life
Eg. androgens (testosterone), estrogen, progesterone, cortisol

12. Epinephrine: one hormone  many effects
Liver cells break down glycogen and release glucose
Blood vessels to skeletal muscles dilate
Blood vessels to intestines constrict

13. Master Glands
Hypothalamus
Pituitary Gland

14. Master Glands Hypothalamus Pituitary Gland
Receives info from nerves and brain
Initiates endocrine signals
Hypothalamus
Posterior pituitary gland:
Oxytocin: contract uterine muscles, eject milk in nursing
Antidiuretic Hormone (ADH): promote H2O retention by kidneys
Pituitary Gland
Anterior pituitary gland:
Follicle-stimulating hormone (FSH): development of ovarian follicles (eggs); promote sperm production
Luteinizing hormone (LH): trigger ovulation; stimulate testosterone production in testes

15. Hypothalamus regulation of Posterior Pituitary gland

16. Hypothalamus regulation of Anterior Pituitary gland

19. Negative feedback systems:
Thyroid hormones
Blood Ca2+ levels
Blood glucose levels
Positive feedback system:
Oxytocin (birthing process; release of milk/suckling)

20. BIOFLIX: HOMEOSTASIS – BLOOD SUGAR

21. Insulin & Glucagon: Control blood glucose levels

22. Control of Blood Glucose
High blood glucose
Liver breaks down glycogen and releases glucose into blood
Insulin released from pancreas
Body cells take up glucose
Liver stores glucose as glycogen
Glucagon released from pancreas
Blood glucose drops

23. Diabetes Mellitus Type I diabetes (10%):deficiency of insulin
Insulin-dependent
Autoimmune disorder  beta cells of pancreas destroyed
Type II diabetes (90%): failure of target cells to respond to insulin
Non-insulin dependent
Insulin produced  cells don’t respond (defect in insulin receptor or response pathway)
Risk factors: obesity, lack of exercise

24. Thyroid Gland Graves’ Disease: Autoimmune disorder
Hypothalamus
TRH
Anterior
pituitary
TSH
Thyroid T3 T4
Graves’ Disease:
Autoimmune disorder
Antibodies bind to TSH receptor
Hyperthyroidism
High temp, sweating, weight loss, high BP

25. Stress and the Adrenal Gland

26. Anabolic-Androgenic Steroid (AAS) Use
Legally prescribed to treat hormone deficiency, loss of muscle mass (cancer, AIDS)
Used to enhance performance and improve physical appearance

27. Effects of AAS Abuse Source: www.drugabuse.gov/infofacts/steroids.html
aggression
extreme mood swings
liver damage
jaundice
fluid retention
high blood pressure
increases in LDL (“bad” cholesterol)
decreases in HDL (“good” cholesterol)
renal failure
severe acne
For men—shrinking of the testicles, reduced sperm count, infertility, baldness, development of breasts, increased risk for prostate cancer
For women—growth of facial hair, male-pattern baldness, changes in or cessation of the menstrual cycle, enlargement of the clitoris, deepened voice
For 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 spurt
In addition, people who inject AAS run the added risk of contracting or transmitting HIV/AIDS or hepatitis.