The meaning of interaction and coordination in multicellular beings.
Interaction and coordination in humans: stages involved (from stimuli to receptors); organ systems involved (receptors, nervous system, endocrine system and motor apparatus).
Receptors: internal and external; types according to the stimuli detected, how the eye works; how the ear works; the skin as a receptor.
The nervous tissue: neurones (and their structure) and glial cells, nerves, nerve impulse, synapse, neurotransmitters.
The nervous system: structure, main organs (and their functions), types of nerves, types of nervous circuits.
The endocrine system: endocrine glands, hormones (main kinds and their effects), target organs and target cells, stages and types of endocrine coordination, endocrine glands as effectors.
Homeostasis: how the human body controls the internal temperature and the levels of fluids and metabolites.
The motor apparatus: main muscles and bones; the muscles as effectors.