When you step out in bright sunlight, you partly close your eyes to keep away the bright light. You may start sweating as the temperature rises. These are coordinated responses to stimuli. In animals the responses are quicker than in plants.
Response and coordination in animals involve the sense organism the nervous system and hormones.
Human nervous system consists of :
central it consists of brain (which has the centres for hunger, thirst, thinking, maintaining posture, speech, writing) and spinal cord - (which take care of reflex actions e.g. response to pricking of pin),
peripheral : which controls voluntary actions e.g. running
autonomic which controls involuntary action e.g. respiration.
Have you ever thought why some kids are tall and some are short in your class? This variation is due to inheritance of hormones. What are hormones? Where do they come from? Hormones are secreted by endocrine glands(ductless) of endocrine system directly into blood stream. The endocrine system consists of
pituitary gland which secretes growth hormones and controls growth
thyroid gland which secrets thyroxin that controls metabolic rate
adrenal gland which secretes adrenaline that prepares body for emergency
pancreas secretes insulin that regulates blood sugar level
ovaries secretes estrogen and testes secretes testosterone that help in development of secondary sexual characters.
Control and Coordination
Learnhive Lesson on Control and Coordination in Human beings