Although almost 80% of the atmosphere is made up of nitrogen gas, most living things don't have the enzymes necessary to use nitrogen directly from the atmosphere. How
we obtain the nitrogen we need to make proteins and DNA if we can't obtain it from
breathing?

Which supports the idea that birds and butterflies both have wings but they do not have a common ancestor with wings? a. the wings are analogous structures that evolved differently and do not have a similar internal structure. b. the wings are homologous structures that evolved differently and do not have a similar internal structure. c. wings of birds are vestigial structures, but the wing structures of bats are not vestigial. d. wings of bats are vestigial structures, but the wing structures of birds are not vestigial

How is the atomic number of a nucleus changed by alpha decay

Which of these is an intensive property of a substance