What special cells and tissue do flatworms have in their excretory and nervous system

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.

How would you expect the mrna codons that code for the amino acids that make up hemoglobin to compare between humans

The fluid mosaic model of the membrane proposed that membranes