The D7000 bracketing feature allows you to take 2 or 3 sequential photos at 1/3 to 2 stop intervals. The camera does not combine the images and assumes that HDR will be accomplished in post processing.
The D7000 does process two images for long exposure noise reduction where it takes a second photo of equal duration with the shutter closed and subtracts the artifacts of the "blank" image from the real image to eliminate noise artifacts produced by the camera. That's the only time I'm aware of where the camera combines two images.
"Red is gray and yellow white, but we decide which is right ....and which is an illusion"