Chapter 18, Problem 11A

Summary Introduction

To determine:

The living organism owe their life to bacteria.

Introduction:

Bacteria are the single cellular prokaryotic organism. They lack a true nucleus and have a very simple cellular design. They are known to be existing since life begin on the earth. Some of the bacteria are free-living, but many of them are parasitic and commensal in nature. Cyanobacteria are one of such bacteria that have capability to perform photosynthesis and some of them can also perform nitrogen fixation.

Explanation of Solution

In the past, the cyanobacteria were the only organism which have ability to reduce the carbon and nitrogen present in the atmosphere. This helped the bacteria to evolve and give rise to different types of photosynthetic organism.

In case, the cyanobacteria would not have been evolved in past, the plant species would not have existed. The plants are the responsible for the food, so, without evolution of bacteria many species would not have existed.

The bacteria in the atmosphere play very important role in fixing nitrogen, carbon, decomposing, and as food source for many organism. In addition to that, many of the bacteria, which live in commensal relationship with the organism, help in digestion in the gut and production of necessary chemical for the proper absorption of the nutrients.