The Biology I Course was developed through the Ohio Department of Higher Education OER Innovation Grant. The course is part of the Ohio Transfer Assurance Guides and is also named OSC003. This work was completed and the course was posted in October 2019. For more information about credit transfer between Ohio colleges and universities, please visit: www.ohiohighered.org/transfer.Team LeadCathy Sistilli                                         Eastern Gateway Community CollegeContent ContributorsLisa Aschemeier                                 Northwest State Community CollegeShaun Blevins                                     Rhodes State CollegeRachel Detraz                                     Edison State Community College                                     Sara Finch                                          Sinclair Community CollegeWendy Gagliano                                 Clark State Community College AJ Snow                                             University of Akron Wayne CollegeLibrarianAmanda Rinehart                               Ohio State UniversityReview TeamJessica Hall                                        Ohio Dominican UniversitySanhita Gupta                                    Kent State UniversityErica Mersfelder                                 Sinclair Community College

Food provides the body with the nutrients it needs to survive. Many of these critical nutrients are biological macromolecules, or large molecules, necessary for life. Different smaller organic molecule (monomer) combinations build these macromolecules (polymers). What specific biological macromolecules do living things require? How do these molecules form? What functions do they serve? We explore these questions in this chapter.

As with people, it is vital for individual cells to be able to interact with their environment. In order to properly respond to external stimuli, cells have developed complex mechanisms of communication that can receive a message, transfer the information across the plasma membrane, and then produce changes within the cell in response to the message. In multicellular organisms, cells send and receive chemical messages constantly to coordinate the actions of distant organs, tissues, and cells. The ability to send messages quickly and efficiently enables cells to coordinate and fine-tune their functions.

Cell reproduction is a process of cell division that divides one cell into two identical cells.  In multicellular organisms cell reproduction can be for growth, development or repair, whereas in single cell organisms it is a mechanism of reproduction.  The focus of this content is the cell cycle in eukaryotic cells, regulation of the cell cycle, and consequences of a lack of regulation in the context of cancer. A summary of binary fission in prokaryotic cells is also included.

Your body has many kinds of cells, each specialized for a specific purpose. Just as we use a variety of materials to build a home, the human body is constructed from many cell types. For example, epithelial cells protect the body's surface and cover the organs and body cavities within. Bone cells help to support and protect the body. Immune system cells fight invading bacteria. Additionally, blood and blood cells carry nutrients and oxygen throughout the body while removing carbon dioxide. Each of these cell types plays a vital role during the body's growth, development, and day-to-day maintenance. In spite of their enormous variety, however, cells from all organisms—even ones as diverse as bacteria, onion, and human—share certain fundamental characteristics.

Plants and animals must take in and transform energy for use by cells.  Plants, through photosynthesis, absorb light energy and form organic molecules such as glucose.  Glucose has potential energy in the form of chemical energy stored in its bonds.  This chapter covers the metabolic pathways of cellular respiration and describes the chemical reactions that use energy in glucose and other organic molecules to form adenosine triphosphate (ATP).  ATP is the cell’s “energy currency” fueling virtually all energy requiring processes.  The chemical reactions of cellular respiration are a series of oxidation- reduction (redox) reactions that are divided into three stages: glycolysis, the citric acid cycle and oxidative phosphorylation.    

The theory of evolution is the unifying theory of biology, meaning it is the framework within which biologists ask questions about the living world. Its power is that it provides direction for predictions about living things that are borne out in ongoing experiments. The Ukrainian-born American geneticist Theodosius Dobzhansky famously wrote that “nothing makes sense in biology except in the light of evolution.” He meant that the tenet that all life has evolved and diversified from a common ancestor is the foundation from which we approach all questions in biology.

This chapter outlines information on the regulation of gene expression in both prokaryotes and eukaryotes.  This includes transcriptional, post-transcriptional, translational and post-translational regulation.