MAnet: mobile ad-hoc networks
As I know ad-hoc networks are such a network without any central point. i.e. in an ad-hoc networks, members should do everything (such as routing, topology construction and ...) by themselves. Members of an ad-hoc networks are powerful nodes such as laptop. energy is not a bottleneck in ad-hoc networks.
at the opposite, in sensor networks, nodes are sensors, with limited power. enery is very important in sensor networks. So nodes, themselves, cannot run very consuming algorithms such as topology construction. Therefore, these complex algorithms will be run by an access point and the result will be sent to sensors.