Dna is made of two chains of nucleotides. which type of bonds hold the chains together? hydrogen bonds covalent bonds ionic bonds polar covalent bondsdna is made of two chains of nucleotides. which type of bonds hold the chains together? hydrogen bonds covalent bonds ionic bonds polar covalent bonds

metamorphism is the change of minerals or geologic texture (distinct arrangement of minerals) in pre-existing rocks (protoliths), without the protolith melting into liquid magma (a solid-state change). the change occurs primarily due to heat, pressure, and the introduction of chemically active fluids. i hoped i !

cells spend most of their time in interphase