Biology 2e is designed to cover the scope and sequence requirements of a typical two-semester biology course for science majors. The text provides comprehensive coverage of foundational research and core biology concepts through an evolutionary lens. Biology includes rich features that engage students in scientific inquiry, highlight careers in the biological sciences, and offer everyday applications. The book also includes various types of practice and homework questions that help students understand—and apply—key concepts. The 2nd edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Art and illustrations have been substantially improved, and the textbook features additional assessments and related resources.

By the end of this section, you will be able to do the following:

List the steps in eukaryotic transcription
Discuss the role of RNA polymerases in transcription
Compare and contrast the three RNA polymerases
Explain the significance of transcription factors

By the end of this section, you will be able to do the following:

List the different steps in prokaryotic transcription
Discuss the role of promoters in prokaryotic transcription
Describe how and when transcription is terminated

By the end of this section, you will be able to do the following:

Describe the different steps in RNA processing
Understand the significance of exons, introns, and splicing for mRNAs
Explain how tRNAs and rRNAs are processed

By the end of this section, you will be able to do the following:

Describe the different steps in protein synthesis
Discuss the role of ribosomes in protein synthesis

By the end of this section, you will be able to do the following:

Explain the “central dogma” of DNA-protein synthesis
Describe the genetic code and how the nucleotide sequence prescribes the amino acid and the protein sequence

Biology is designed for multi-semester biology courses for science majors. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.

By the end of this section, you will be able to do the following:

Describe the functions proteins perform in the cell and in tissues
Discuss the relationship between amino acids and proteins
Explain the four levels of protein organization
Describe the ways in which protein shape and function are linked

The endoplasmic reticulum (ER) orchestrates different cellular processes by which proteins are synthesized, correctly folded, modified and ultimately transported to their final destinations. As part of this crucial biosynthetic process, proteins that are not properly folded and consequently detrimental to normal cellular function are constantly generated. A common signature of many neurodegenerative diseases, including Alzheimer's and Parkinson's, is accumulation and deposition of misfolded proteins that arise when the ability of cells to deal with the burden of misfolded proteins is compromised. In this course, we will explore how the ER quality control machinery ensures that only properly assembled proteins exit the ER while distinguishing between nascent proteins en route to their biologically active folded state from those that are terminally misfolded.

The MIT Biology Department core courses, 7.012, 7.013, and 7.014, all cover the same core material, which includes the fundamental principles of biochemistry, genetics, molecular biology, and cell biology. Biological function at the molecular level is particularly emphasized and covers the structure and regulation of genes, as well as, the structure and synthesis of proteins, how these molecules are integrated into cells, and how these cells are integrated into multicellular systems and organisms. In addition, each version of the subject has its own distinctive material.

The goal of proteomics is to analyze the varying proteomes of an organism at different times, in order to highlight differences between them. Put more simply, proteomics analyzes the structure and function of biological systems. [8] For example, the protein content of a cancerous cell is often different from that of a healthy cell. Certain proteins in the cancerous cell may not be present in the healthy cell, making these unique proteins good targets for anti-cancer drugs. The realization of this goal is difficult; both purification and identification of proteins in any organism can be hindered by a multitude of biological and environmental factors. [9]