endocrine system

• Hormone 


  A signalling molecule released from endocrine glands that regulates the growth or activity of target cells.
• Signalling molecules 


  A molecule which can interact and initiate a response in a target cell.
• endocrine system 


  the collection of glands in animal responsible for producing hormones that can be transported in the bloodstreams to regulate distant organs/cells.
• gland

  a group of cells that secretes chemical substances to regions of the body or discharges them into the surroundings
• Cells communicate by sending and receiving signalling molecules.
• Hormone molecules function by binding to specific receptors on target cells that are complementary to hormones, that elicit a response in the target cells.
• hypothalamus

  a small region of the brain located above the pituitary gland in mammals that controls much of the body's internal temperature via hormone secretion, and influences the function of the pituitary gland. It allows the nervous system and endocrine system to communicate with one another via neuro-hormones.
• neurosecretory cells in the hypothalamus detect signals from the nervous system and then secrete neurohormones into the blood
• Neurohormones help regulate; water balance, temperature regulation, sleep and emotional activity