Don't look if you're squeamish

I apologise if this is a bit gross but I think it's interesting so some of you might too. According to the receipt from the butcher it's a lamb's heart and lungs but we all thought it was a cow as the heart is enormous compared to most we get in.
I'm going to show it to my year 8s on Wednesday (it will be frozen between now & then) as we're doing breathing and respiration so I wanted to check it out today & make sure the lungs inflate when you put a tube down the trachea & blow. It's a bit gross but also very cool!