Answer:
I can be winding and I can be straight. I can be smooth and I can be rough. Sometimes both. I start out black but fade to brown. My favorite colors are yellow and white and I love stripes and dashed lines.
I go up and never come down no matter how hard you wish. As I get higher, more wrinkles crawl on to the face. What am I?
I'm as simple as a circle worthless as a leader; but when I follow a group their strength increases tenfold. By myself I'm practically nothing.
I can be in your body but never on your placemat. I'm always better when I'm fresh, but you'll never see me in the flesh. What am I?
What can run but never walks licks but never talks has a bed but never sleeps has a mouth but never eats?
It has no top or bottom, but it can hold flesh, bones, and blood all at the same time.