Cell: the smallest structural and functional unit of an organism, typically microscopic and consisting of cytoplasm and a nucleus enclosed in a membrane.
Microbiome: a community of microorganisms (such as bacteria, fungi, and viruses) that inhabit a particular environment and especially the collection of microorganisms living in or on the human body
Bacteria: a member of a large group of unicellular microorganisms which have cell walls but lack organelles and an organized nucleus, including some that can cause disease.
Infection: the process of infecting or the state of being infected.
Explanation: Both provide each other with the necessary ingredients for the process to take place: glucose and oxygen for cellular respiration, carbon dioxide and water for photosynthesis.
