# How do I animate a point and an position vector along an animated parametric curve?

I have created the following animation:

Animate[ParametricPlot[{Cos[y], Sin[y]}, {y, 0, a},
PlotRange -> {{-1.5, 1.5}, {-1.5, 1.5}}], {a, 0.01, 2 Pi}]


How do I

1. highlight the most advanced point on the curve (i.e. add another graphics point animation with coordinates dependant on the same a variable)
2. draw a connecting vector from the origin to the continuously moving point

Thanks!

EDIT: A similar problem is described here, however the curve isn't animated. I would like the curve to be included in the animation.

Animate[Show[

Additionally, you may replace Line[] with Arrow[] if you want the vector to have an arrow