The core area surrounding the heart and internal organs.
The inside
Your body heats up, the feeling of temperature is relative.
evaporation
Sweat is water
I think the first body part to cross the line stops the time.
every part of the body senses change, but if the question means which part senses first, the answer is the heart.
The part that was bitten
The Brain :)
your head(brain)
lungs
The anus of the animal because it is the warmest and most tenderest part of the body.
There are a few body parts that start with the letter B. One body part that starts with B is bicep.