Polar Bear

What is a central idea of paragraphs 3 through 6?

• PFAS chemicals are used in many everyday products.

• Polar bear fur is better at repelling ice than some human-made products.

• Scientists want to create safer alternatives to PFAS by studying polar bear fur.

• Forever chemicals can cause health problems including cancer.

How does the information in the section "A Slick Solution" support a central idea of the article?

• It explains why polar bears are good hunters in the Arctic.

• It describes the experiments scientists conducted with polar bear fur.

• It reveals what makes polar bear fur resistant to ice and how this might help replace PFAS.

• It shows that human hair can also resist freezing in cold temperatures.

Which detail would be most important to include in a summary of the article?

• PFAS can remain in the environment for hundreds of years.

• The grease in polar bear fur contains a mixture of lipids.

• One scientist cut his hair for the experiment with ice blocks.

• Polar bears have white fur that helps them survive in the Arctic.

How did scientists test the polar bear fur's resistance to ice?

• They observed polar bears hunting in their natural habitat.

• They compared samples of washed and unwashed polar bear fur to human hair.

• They asked Inuit people about their experiences with polar bear pelts.

• They measured how long it took for ice to form on different materials.

According to the passage, why is PFAS harmful?

• It makes products too expensive for most people to afford.

• It prevents animals from surviving in cold environments.

• It stays in the body and environment for a very long time.

• It doesn't work as well as natural substances from animals.

The purpose of the information in paragraph 8 is to show that

• polar bears are the most dangerous predators in the Arctic.

• polar bears need to eat seals to survive in the Arctic.

• seals are difficult to catch because they spend most time underwater.

• the ice-resistant fur gives polar bears an advantage when hunting.

According to paragraphs 12 through 14, how does the grease on polar bear fur affect its interaction with ice?

• It prevents ice from sticking to the fur, similar to how PFAS works.

• It makes the fur waterproof so bears don't get wet when swimming.

• It helps the bears stay warm by trapping heat close to their bodies.

• It makes the fur appear white, which helps with camouflage on ice.