Transcript Hormones
Chapter 45
Hormones and the
Endocrine System
Overview
Metamorphosis – controlled by
hormones
Hormones – secreted into extracellular
fluid/circulates in blood or
hemolymph/communicates regulatory
*messages
*only target cells have receptors
Overview(con’t)
Hormones regulate – reproduction,
growth, metabolism, behavior
45.1 Hormones and other signaling molecules bind
to target receptors, triggering specific response
pathways
Types of Secreted Signaling Molecules
1. Hormones – endocrine vs exocrine
2. Local Regulators – paracrine vs
autocrine signaling
3. Neurotransmitters and
Neurohormones - synapse
4. Pheromones
Intercellular Signaling
Synaptic Signaling
Neurohormones
Pheromones
Chemical Classes of Hormones
1. polypeptides
2. amines
3. steroid hormones
Water soluble or lipid soluble
http://bcs.whfreeman.com/thelifewire/cont
ent/chp42/4202s.swf
Center for BioMolecular Modeling
Action of Epinephrine on a Liver Cell
Thyroid Hormone Animation
Scientific Inquiry
Location of receptors and their
interaction with hormones???
Rats and estradiol(radioactive form)
Frogs and melanocyte-stimulating
hormone(MSH)
Fig. 45.4 – What if?
Multiple Effects of Hormones
Water-soluble hormone – tissues vary
in response due to different receptors or
signal transduction pathways
Fig. 45.8 p. 980
Lipid-soluble hormone – different
effect on different target cells Ex)
estrogen
- different effect in different species Ex)
thyroxine
Signaling by Local Regulators
Cytokines
Growth factors
Nitric oxide
Prostaglandins
Nitric Oxide
Aspirin and prostaglandins
45.2 Negative feedback and
antagonistic hormone pairs
A) Simple Hormone Pathways – low pH
in duodenum secretin pancreas
bicarbonate reduction in stimulus
B) Insulin and Glucagon – an antagonistic
pair – see Fig. 45.12 p. 983
- alpha and beta cells of pancreas
Control of Blood Glucose
Diabetes Mellitus
Deficiency in insulin or a decreased
response to insulin
Type I – autoimmune/insulin
dependent/destroys beta cells
Type II – heredity and excess body
weight/target cells are non-responsive
http://professional.diabetes.org/admin/Use
rFiles/0%20%20Sean/FastFacts%20March%202013.pdf