How do chemistry and biology relate?
Every activity that sustains life on the planet takes place only because of the chemical properties of the atoms, molecules and compounds involved.
There is a saying that claims that Biology only works because of Chemistry and Chemistry only works because of Physics.
Biological processes of living organisms depend upon the interactions of the atoms, molecules and compounds that make up living tissues and the environment in which life takes place.
The structural composition of living organism begins with atoms making molecules and compounds, molecules and compounds forming organelles, organelles forming cells, cells forming tissues, similar tissues with similar functions for organs, organs function to form systems and systems form the multicellular organisms that roam the planet from fungi to plants and plants to animals. Not to mention all of the unicellular organisms that also interact in the living systems that sustain life on this planet.
We can begin with the fact that the earth's biosphere is about 75% water and living cells are also 75% water. Water is composed of an atom of Oxygen bond to two hydrogens by sharing an electron with each Hydrogen in a molecular bond that creates a slightly higher positive charge on each hydrogen and a slightly higher negative charge on the Oxygen. This arrangements of the atoms and their charges make water a polar molecule. The fact that water molecules are polar gives them unique properties of adhesion (they like to adhere to surfaces) and cohesion (they like to join together).
These properties properties of water make is the universal solvent, capable of dissolving almost any material. Makes water less dense as a solid (ice) then as a liquid (water), which is why ice floats in a refreshing glass of iced tea. Water's polarity creates spaces between the molecules to hold dissolved materials like salt in the sea water.
Water is the primary material in cytoplasm and blood which allows for the transport of materials in both unicellular and multicellular organisms. Water is the Hydrogen donor in the energy exchanges that take place in photosynthesis and cellular respiration. The hydrogen and hydroxide molecular bond of water makes it act as both an acid and a base providing Hydrogen ions and hydroxide ions for an infinite number of chemical reactions that take place at the cellular level.
Basically, this is a long winded answer that hopefully gets each of us to understand that every activity that sustains life on the planet takes place only because of the chemical properties of the atoms, molecules and compounds involved. Whether it is a plant undergoing photosynthesis by removing carbon dioxide from the atmosphere in order to create glucose and oxygen for aerobic respiration in an animal or the complex ionic dance of the sodium and potassium pump that allows nerves to transmit information, everything living thing depends upon Chemistry for life on earth to continue.