表皮
abstract
allium
background
biology
botany
cell
closeup
color
detail
flail
layer
light
macro
magnification
many
membrane
micro
micrograph
microscope
microscopic
nature
nuclei
nucleus
onion
organic
pattern
photo
photomicrograph
photomicroscopy
pigmented
pink
plant
research
science
skin
structures
texture
vascular
wall