assuming that all vegtables are root crops ;D sadly they're not besides some fruits grow in shrubs and vines like strawberrys and grapes and some do grow out of the ground, like pineapples
it's determined on rather if it has seeds or not. no seeds mean it's a vegetable and seeds mean it's a fruit. that's the general rule of thumb but it get's more complicated when you introduce things that don't have seeds and are a fruit [grape fruit for instance].
All plants have seeds don't they? If you mean the by-product of the plant okra has seeds in it, tomato, eggplant, pumpkins and squash have seeds <- some people consider it vegetables and some fruit
I've been running a bit of an experiment on myself, I've been trying to get by without fruit or vegtables. i eat cereals like rice, wheat oats and pasta. I've been on this diet for about 6 months now and have noticed an increase in my stamina, energy levels and good mood. It's meatetarianism or something... :-[
you can get different vitamins and minerals from fruits and vegetables so its always good to have a balance in what you eat