Autopsy
Dissection
noun, verbal noun
Divide a body and untie its organs to perform an autopsy. You have to cut it all up and untangle the parts to see why this person or animal died.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
解剖をしてみないと何とも言えません。
We can't say anything until we perform an autopsy.