As part of a class activity, a science teacher blindfolded students and then asked them to touch a 3-D model of a cell.

One student felt a thin, flexible layer around the cell. Another student felt an organelle that had the texture of sandpaper. Which organelle did the first student feel? Which organelle did the second student feel?

The thin external covering is similar to the
. The organelle with a texture like sandpaper is the
.