Endocrine glands produce hormones (peptides, proteins, lipids) which fit into specific receptor molecules on target cells to trigger a change in intercellular activity

Homeostasis: maintenance of constant internal body environment.

Two systems are involved:

1) Sympathetic nervous system (stimulates)

2) Parasympathetic nervous system (inhibits)


  • homeostatic mechanism increases the change and brings factor further from resting level


  • homeostatic mechanism reverses the change and restores factor to resting level

In the dermis, there are receptors to different stimuli:

1) thermoreceptors

2) pacinian corpuscles

3) meissner’s corpuscles

4) free nerve endings

For thermoregulation, there are two types of organism:

1) endotherms (produce and maintain body temp.)

2) exotherms (rely on environment to maintain body temp.)