Because technically there is no such thing as cold
all that exists is heat
this is because heat is the rapid movement of particles, made by friction (to understand why you must delve into physics and some chemistry)
so, when you feel cold, it's really the absence of heat
so instead of "keeping the cold out", which makes no sense at all scientifically, insulation keeps the heat in.
as a side note
the feeling of cold is produced when you come in contact with an object (yes, air counts) that has less heat, or energy, than you do, You feel cold because heat (energy) from your body is being transferred to the environment. This ABSENCE OF HEAT in your body is why you feel cold
The correct answer is d
Hope this helps :DD
Enzymes are proteins and they control the speed of chemical reactions in your body. Without them, the reactions would happen too slowly to keep you alive.
Some break down larger molecules into smaller ones and those enzymes are in your stomach.
