Bacteria are simple prokaryotic organisms which lack membrane bound organelles. On the other hand, birds like higher organisms are eukarotyotic organisms with proper membrane bound organelles. Other than this that both bacteria and birds are living organisms, one way in which bacteria and birds are similar is that they both have DNA as genetic material which they pass to their offspring. Although in the case of bacteria there is no variation is offspring however in case of birds there can be because genetic shuffling takes place and offspring is not an exact replica of parents while in case of bacteria they are.
Answer: the functions of the skeleton. Structure, protection (ribs), allow movement, chemical/physiological: stores calcium and the tissues are made up of the same material
