Without bacteria in the environment

a. adequate amounts of carbon would not be available to living organisms.
b. plants would not be able to grow due to lack of nitrogen.
c. bioremediation would have limited use as a tool to clean up pollutants.
d. there would be a shortage of decomposer organisms.
e. all of the choices are correct.

e. All of the choices are correct.

Explanation: Bacteria is an important part of the ecosystem. There are some bacterial species which we called (biological nitrogen fixation (BNF). These bacteria fixes atmospheric nitrogen for higher plants. There are some other bacterial species which feed on dead bodies of living material and helps in cleaning the environment. Due to this decomposition process high amount of carbon is liberated in the atmosphere and used by the plants during photosynthesis.

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.

it should be d) transitional fossils.

they show the gradualism of evolution throughout a period of time