CHAPTER 45 HORMONES & ENDOCRINE SYSTEM

Long Distance RegulatorsI. Endocrine system

A. Hormones Blood/HemolymphII. Nervous system

A. Neurons

Signaling moleculesI. Types of signaling

A. Endocrine signaling1. Blood stream Target any cell in body

B. Paracrine signaling1. Diffuse locally affect local cells only

C. Autocrine signaling1. Local regulators that affect cells that release

D. Synaptic signaling1. Short distance

E. Neroendocrine1. Blood stream Target any cell in body

II. Classes of hormomesA. H2O soluble

1. Polypeptidesa. Proteins/peptides

2. Aminesa. Amino Acids

B. Lipid soluble1. Steroids

a. Lipids

III. Cellular response pathwaysA. Water soluble hormones

1. Signal transduction pathways

2. Travel freely through bloodstream3. Cannot enter directly through

plasma membrane

B. Lipid soluble hormones1. Enter directly through plasma

membrane2. Must attach to transport protein to

travel through blood

IV. Multiple effects of hormones

45.2 Negative feedback & antogonistic hormone pairs

I. Simple hormone pathwaysA. Negative feedback

B. Example Insulin & glucagon: Control of blood glucose1. Insulin decrease blood glucose levels

a. Target body cells outside of brain1. Increase uptake & storage 2. decrease glycogen breakdown in liver

2. Glucagon Increase blood glucose levelsa. Target Liver cells

3. Diabetes Mellitusa. Inability to control glucose homeostasis

1. Blood glucose levels increase2. Body is incapable of removing glucose for blood

a. Lack insulin production Type Ib. Decreases response to insulinType II

b. Type I (insulin-dependant) inherited1. “Juvenile” diabetes2. Autoimmune disorder

a. Immune system destroys beta cells of pancrease1. Insulin not made

3. Insulin injections

c. Type II (non-insulin dependent)1. “Adult onset” diabetes2. Target cells fail to respond to insulin

a. Insulin is produced3. Heredity, obesity, lack of exercise4. Controlled through diet

45.3 Endocrine & Nervous SystemI. Coordination in vertebrates

A. Hypothalamus 1. Endocrine gland2. Receives nerve signals from body and brain

a. Initiates endocrine signalingb. Signaling travels to pituitary gland

B. Pituitary glands1. Posterior pituitary gland

a. Stores and secretes 2 hormones synthesized by hypothalamusb. Oxytocin

1. Mammalian milk release during nursing2. Uterine contraction during birth3. Positive feedback

c. Antidiuretic hormone (ADA)

2. Anterior pituitary glanda. Synthesizes and secretes a variety of hormones (Table 45.1)b. Controlled by the hypothalamus

1. Releasing or inhibiting hormone

45.4 Endocrine Glands & their HormonesI. Thyroid Hormone

A. Regulated by Thyroid Stimulating Hormone (TSH)B. Controls a variety of metabolic processesC. Iodine a major component to thyroid hormones

1. Deficiencies can result in a variety of metabolic disorders2. Dietary iodine crucial for proper thyroid function

a. Seafood & iodized salt

II. Parathyroid hormoneA. Controls blood Ca2+

III. Adrenal Hormones: Response to stressA. Epinephrine (adrenalin) and Norepinephrine

1. the “fight or flight” response2. Affects

a. Increase available energy1. Increase glycogen breakdown in liver and skeletal muscle2. Increase glucose release by liver3. Release of FA from fat cells

b. Increase both HR and stroke volume

c. Dilate bronchioles

d. Alter blood flow1. decrease to skin, digestive organs, and kidneys2. increase to heart, brain, skeletal muscles