My first impression - yowza, that's bright! I'd have guessed this was taken outdoors but checking the info it's a studio shot - nice job recreating a bright afternoon in the studio. I do like the contrasts/similarities in the textures of the leaf and the paper, but my favorite part is the very definite shadow. The dark veins in the leaf are quite intriguing as well - makes it seem as though the leaf has actual blood running in them.
Composition overall is good - simple but effective. What may have hurt your score, other than some simply finding it too bright, is texture studies tend to be just that - overall studies of texture with no particular focus. To some this may be disconcerting - they want somewhere specific for their eyes to go.