In a clade, mammalian has the three descendents: monotreme, marsupials, and eutheria. what will these three descendants together be called?

twin groups
nodes
sister groups

Molecular models of two different substances are shown below. in the molecule on the left, the oxygen atom pulls on electrons more strongly than the hydrogen atoms. in the molecule on the right, the two oxygen atoms pull on the shared electrons with the same strength. water molecule, h,o oxygen molecule, oz when the two substances are put in the same container, they do not attract each other. why does this happen? a. they both contain oxygen. b. one is polar and one is nonpolar. c . they are both polar. d. they contain different elements.

What is a photon? a. part of a ribosome b. a light particle c. a carbon dioxide molecule d. part of a chloroplast b.a light particle

Which of the following determines the specificity of a dna probe? a. type of radiation b. level of enzymatic activity c. number of neutrons d. complementary base pairing