imported>Stwikiadmin: Created page with "{| class="wikitable" style="color:black; background-color:#ddd; margin-left: auto; float:right" | Biology: | Fat Insulation |- | Grade Range: | Elementary School |- | For..."

2016-08-17T16:58:31Z

Created page with "{| class="wikitable" style="color:black; background-color:#ddd; margin-left: auto; float:right" | Biology: | Fat Insulation |- | Grade Range: | Elementary School |- | For..."

New page

{| class="wikitable" style="color:black; background-color:#ddd; margin-left: auto; float:right"
| [[Biology]]:
| Fat Insulation
|-
| Grade Range:
| [[Elementary School]]
|-
| Format:
| [[Hands-on]]
|}

This demonstration is a favorite among young students, and a compact, easy to perform demonstration for science nights. One should be sure to bring paper towels, since water will almost definitely be spilled!

== Materials ==
;Polar Bear Glove Preparation:
* Plastic Sandwich Bags
* Alternative: A Gallon Size Bag
* Shortening
* Duct Tape
;Presentation:
* Bowl
* Ice
* Water

== Safety Precautions ==

Please read the Cryogen Safety section of the [[Demonstration Safety]] page before performing this demonstration.

== Demonstration ==
;Preparation:
* Create the Polar Bear Glove: scoop several spoonfuls of shortening into a sandwich bag. Put a second sandwich bag over one hand, and push it inside the bag with shortening and smooth it out. Add shortening into the bag if necessary until the outer bag is filled smoothly around the inner bag. seal the edges of both bags together using the duct tape, making sure they are sealed fully around the outside.
* Alternative: Fill a gallon sized bag with enough shortening to make a semi-thick layer throughout the bag while flat on a table. close the bag, and use duct tape to seal it firmly. Put a sandwich bag on one hand, and place it on top of the gallon bag, with the sealed end towards your wrist. Wrap the bag around your hand, and duct tape it together so it stays wrapped around your hand. finally, duct tape the lip of the sandwich bag to the gallon bag so they stay together.

;Presentation:
# Set out the bowl and fill it with ice and water. When students come up, ask them to hold one hand in the ice water for several seconds. How cold is it? Do they think they could keep their hand in very long? Why or why not?
# Have them put the polar bear glove on and put their hand back into the water. Be sure they don't put their hand in far enough for water to come into the glove as well. Ask the student if the water is more tolerable with the glove on. Do they think they could keep their gloved hand in very long? Why or why not?

== Why This Works ==

Some animals, such as polar bears, live very far north or south in extremely cold environments. In these environments, the animals need to be able to keep warm to survive, so they often will have a thick layer of fat under their skin. This ''Fat Insulation'' helps their bodies keep heat in, while also keeping the cold out. This is because fat does not conduct heat very well, so the warmth inside a polar bear's body cannot travel well through the fat. Likewise, this means that the cold outside the polar bear cannot affect much below their fur, so the polar bear is able to stay toasty warm all year round.

When a student puts their hand into the ice water, their body heat is quickly lost through their skin into the water. This is because we don't need a thick layer of fat on our bodies to stay warm, so we have very little fat insulation. When the student does it again with the glove, they find that their hand doesn't get cold nearly as quickly, if at all. This is because the shortening in the glove works similar to the fat on a polar bear, and keeps the cold from the water out while keeping the warmth of their hand in.

== Additional Information ==

* This demonstration works well with the [[Predator Prey]] and the [[Blind Spot]] demonstrations.

Polar Bear Glove - Revision history

imported>Stwikiadmin: Created page with "{| class="wikitable" style="color:black; background-color:#ddd; margin-left: auto; float:right" | Biology: | Fat Insulation |- | Grade Range: | Elementary School |- | For..."