All living things are made of cells. Living cells
generally contain water along with all the raw
materials and structures that make the cell work.
Freezing usually damages cells because water
expands when it freezes. Don’t take my word
for that. Take a plastic bottle that someone was
going to throw away and fill it most of the way
with plain water. Use a marker to mark the water
level, then put it in the freezer. The next day,
take a look. The ice will be higher than the mark
you made for the water level. The bottle may even
Animal cells just have thin membranes around
them. When ice crystals form, they destroy the
cells. That’s what frostbite is.
Plant cells have cell walls outside their cell
membranes. This may protect the cells from
bursting, but plants that are not adapted to
freezing can die at freezing temperatures. Many
bacteria have tough cell walls that resist
freezing, so freezing food does not kill most
bacteria, it just sends them into a sort of
hibernation. When the bacteria warm up,
they’re ready to start reproducing and causing
Walls are not the only way to protect cells
from freezing. Water can get very cold without
freezing if it has certain things dissolved in
it. Cars need circulating fluid to cool
engines. People add antifreeze to a car’s radiator
water to keep it from freezing. People in cold
climates sprinkle salt or other things on
sidewalks to melt ice and keep it from forming.
Some cold-adapted species have types of
antifreeze in and between their cells so that
they can be colder than 0 Centigrade or 32
Fahrenheit and still not freeze. Some species
remove a lot of the water from inside their cells
and the spaces between them so that there is less
ice to form.
There’s a great article about this at:
What might be some of the drawbacks to
making anti-freeze or letting yourself freeze?
You may want to study animal physiology.
Thanks for asking,