ACE2 involves a G-protein coupled receptor, which spans the cell membrane how many
times?

Explanation is in the file

cutt.ly/nz6VGda

answer; i believe the correct answer is ( proteins );

one characteristic that is shared by all is a soft body. many

of these invertebrate animals also have an outer shell to protect their

body. oysters, clams, snails, and mussels are all mollusks. so are octopuses, squids, and slugs. mollusks live on land and in freshwater.