What defies a species?

their color, their size, their life I guess

Acord to nature.com a species can be defined as a biological species is a group of organisms that can reproduce with one another in nature and produce fertile offspring. The term species can also be defined as the most basic category in the system of taxonomy.

Explanation:

this protocol provides a detailed procedure for co-immunoprecipitation (co-ip) to identify protein–protein interactions.

photosynthesis makes the glucose that is used in cellular respiration to make atp. the glucose is then turned back into carbon dioxide, which is used in photosynthesis. while water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.