System or process for achieving a certain result.

General situation or state of being. To imagine someone or something in an image.

To make a sudden movement due to surprise.

educational talk to audience. To speak to someone to show anger or warn them.

of nerve cells in which adrenaline, noradrenaline, or similar substance acts as neurotransmitter.

raise levels of physiological or nervous activity in.

chemical substance which is released at end of nerve fibre by arrival of nerve impulse and, by diffusing across synapse or junction. Chemical substances, such as acetylcholine or dopamine, that transmits nerve impulses across a synapse.

Situated in front of or occurring before a synapse.

bewildered. To make something unclear or hard to understand.

junction between two nerve cells, consisting of minute gap across which impulses pass by diffusion of neurotransmitter.

Outside covering of a cell.

sudden strong and unreflective urge.

without changing or stopping. as soon as.

substance which initiates physiological response when combined with receptor. Drug that can combine with a receptor on a cell to produce a physiological reaction.