Rendering models and primitives

I'm trying to wrap my head around the use of effects and their use in rendering models and primitives. The sample code to render a model "m" looks like the following:

foreach (ModelMesh mesh in m.Meshes)
{
foreach (BasicEffect effect in mesh.Effects)
{
effect.EnableDefaultLighting();

effect.View = view;
effect.Projection = projection;
effect.World = MyWorldRotation * mesh.ParentBone.Transform *
Matrix.CreateTranslation(Position);
}
mesh.Draw();
}

While the sample code to render a primitive looks like this:

basicEffect.Begin();
foreach (EffectPass pass in basicEffect.CurrentTechnique.Passes)
{
pass.Begin();

graphics.GraphicsDevice.Vertices[0].SetSource(vertexBuffer, 0,
VertexPositionNormalTexture.SizeInBytes);

graphics.GraphicsDevice.DrawPrimitives(
PrimitiveType.TriangleList,
0,
12
);

pass.End();
}
basicEffect.End();

RTodd wrote:

A couple of questions: Does the call to "mesh.Draw" in the first example contain an EffectPass loop like the one shown for rendering a primitive When a model is loaded, is it normally associated with a BasicEffect effect (it would appear so from the sample) Are they separate instances of the BasicEffect class Would/should you share the same effect instance among more than one model so that effect properties only have to be set once If you're rendering both primitives and models, is there a way to render the models as part of the EffectPass loop used by the primitives Or would you render them separately