Why did my dog bite my nose off after i told my family that i could smell again? ? (it really hurts)

I don't know, is your dog okay?

Maybe your dog senses that you can smell again and wanted to see for himself :O

Otherwise how did you lose your sense of smell?

If your dog is okay, then give he/she food because maybe they think it is food. Or the other option to to pay more attention because dogs might do that for more attention (play with them more)

b) the heart is a pump made of muscle and that is difficult to grow in the lab.