hypercharleyfarley on the BBC Gardening message boards dropped an interesting aside:
‘By the way, Jerusalem artichokes & sunflowers are related - the name’s nothing to do with Biblical names, but a corruption of Girasole - turning to the sun, which is what sunflowers do.’

Further investigation on Wikipedia brought up ‘ when the Jerusalem artichoke was first discovered by Europeans it was called Girasole, the Italian word for sunflower.’

The Jerusalem artichoke (Latin name - Helianthus tuberosus) also called the sunroot or sunchoke or topinambur, has a swollen tuber, which is used as a root vegetable.

The globe artichoke (Latin name -Cynara scolymus) is quite different & a member of the thistle family.

Click the link for more information on growing Jerusalem artichokes in the vegetable garden.