Script doesn't spawn correct part?

The script doesn't spawn the part correctly.

function generatePart(Color)
	local part = Instance.new("Part",game.Workspace)
	part.Anchored = false
	part.Transparency = 0.5
	part.BrickColor = BrickColor.new (Color)
	part.Parent = workspace
end
generatePart("Bright Green")
generatePart()
generatePart()
generatePart()

By the way, I haven't finished the other generate part but it doesn't spawn green part.

Maybe change it to Color3

function generatePart(Color)
    local part = Instance.new("Part",workspace)
    part.Anchored = false
    part.Transparency = 0.5
    part.Color = Color3.new(Color)
end
generatePart(255,0,0) -- Red

while true do
wait(1)
function generatePart(Color)
    local part = Instance.new("Part",game.Workspace)
    part.Anchored = false
    part.Transparency = 0.5
    part.BrickColor = BrickColor.new ( "Bright Green")
    part.Parent = workspace
end
end
generatePart()

You have to supply a parameter for every single one of the times you called the function, or else you will get an error.