Cells are the smallest unit of life. Thus, a cell requires all seven characteristics of living things. I use the acronym MR.GOSEA to remember these characteristics, which are identified and explained below:
M- Maintain homeostasis- All living things need to keep an internal balance. Examples would be blood pressure, blood sugar levels, heart rate, respiratory rate, etc.
R- All living things must reproduce to ensure the survival of their species.
G- All living things grow.
O- All living things show some level of organization. The levels of organization, from smallest to largest, are: atoms, molecules, organelles, cells, tissues, organs, organ systems, organisms.
S- All living things respond to stimuli.
E- All living things either make energy (via photosynthesis that is done within the chloroplast) or release energy (via cellular respiration in the mitochondria).
A- All living things adapt to their external environments.