1. Chemical Signals in Animals
Chapter 45
Chemical Signals in Animals

2. I. Basics
Hormone – chemical signal secreted into body fluids that communicates directly with target cell
Endocrine Gland – secretes hormones into blood
Endocrine systems work very closely with the nervous system
- neurosecretory cells / hormones and signals for n.s.
Basic regulation in insects / BH – ecdysone - JH

4. Local Regulators Mechanisms of Cell Signaling
II. Chemical Signals
Local Regulators
Mechanisms of Cell Signaling

5. A. Local Regulators Growth Factors – stimulate cell proliferation
NO – neurotransmitter, kill cells, dilate vessels
Prostaglandins – induce fever and pain, reproductive system

6. B. Mechanisms of Cell Signaling
Receptor – STP – Response
Receptor in the plasma membrane / activates an enzyme, etc
Receptor in the nucleus / make a certain protein

9. III. Vertebrate Endocrine System
Tropic Hormone – have other endocrine glands as targets
Hypothalamus
- region of lower brain
- secretions of hypothalamus are stored in or regulate the pituitary gland
- posterior pituitary stores oxytocin and ADH made by hypothalamus
- creates releasing and inhibiting hormones to control the anterior pituitary

10. Posterior Pituitary

11. Anterior Pituitary

12. Endocrine Gland Locations

18. Sweet Video