Explanation: Homeostasis is the bodies way to maintain internal environment within normal range despite changing external environment. It achieves this by responding to stimulus using the brain or control centre. Receptors, chemoreceptors or thermoreceptors, in cells senses change in its environment, message is transmitted to the control centre via nerve impulse. Effectors such as organs and muscles receives the message and act accordingly by either enhancing the process as a results of positive feedback loop or inhibit the process from a negative feedback loop.
Therefore the difference is that receptors sense stimulus and transmit a message wheras effectors responds to message received by creating the necessary change needed to main homeostasis.