Assertion: whale's baleen | /r/MadeOf | keratin
Facets:
Source sentences:
text: Baleen are plates made of keratin – the same material that your hair and fingernails are made of.
text: Baleen is made from keratin, the same substance as your fingernails and hair.
text: Baleen are plates made of keratin – the same material that your hair and fingernails are made of.
text: Baleen is made from keratin, the same substance as your fingernails and hair.