Regardless of its size or complexity, each organism carries on the same life processes. Organisms are classified into groups based on their structure and how they carry on these life processes. This chapter reviews the structure of cells and life processes and gives an overview of the classification system. A moneran is a one-celled organism that does not have a nucleus. Another name for monerans is bacteria.
Viruses are the smallest living things.
They are actually not even cells, but are included in the study of living things because once they are inside a cell they reproduce. This chapter reviews these three types of microscopic life and describes their activities. Many fungi are harmful to humans, but some, such as yeast, are very helpful. This chapter reviews the types of fungi, including yeast, mold, and mildew, and how they get their food. Life Sciences - Invertebrates Invertebrates are animals which have no backbones.