Chapter 1, Problem 1RQ

Summary Introduction

To review:

The contradictions in defining microbiology as a study of microscopic organisms or as single-celled organisms.

Introduction:

A microbe or a microorganism is defined as an organism that cannot be seen with the naked eyes and requires the use of a microscope. They exist in mountains, deserts, poles to equator, geysers, lakes, and the deep in the oceans. Some are suited to survive in the harsh conditions such as extreme hot or cold and under high pressure as well.

Explanation of Solution

Microorganisms are quite diverse and include bacteria, fungi, algae, and protozoa. Most microorganisms are unicellular, but this is not standardized or universal and has many contradictions because of the microscopic nature of some multicellular organisms and even the size of few microorganisms. Some protists, like the amoeba, are capable of growing to sizes that are visible to the naked eye.

There are also certain sulfur bacteria and plant algae that grow long leaflike extensions without undergoing cell division. There are some multicellular worms and arthropods that require a microscope to be seen but they are not considered microbes. Mushrooms and biofilms are complex organizations of cells that are differentiated into various types based on their functions. A virus has genetic material but is an acellular particle that takes over the metabolism of the host cell. Although viruses are not functioning cells, some viral genomes may have evolved from cells.