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:Discuss the different types of mutations in DNAExplain DNA repair mechanisms

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Cancer-associated fibroblasts, or CAFs, make up 50 to 90% of a solid tumor’s volume. Embedded between a tumor’s core and healthy tissue, CAFs contribute to tumor initiation, progression, and invasion, and according to a new study, CAFs might also contribute to tumors’ ability to resist radiation therapy. Researchers coaxed CAFs to form by culturing normal fibroblasts with cancer cells from different tissues, including the breast, brain, lung, and prostate. Compared to normal fibroblasts, these CAFs showed less DNA damage from gamma ray radiation. This “radioresistance” was linked to DNA repair machinery deployed by CAFs. Treating CAFs with molecules inhibiting the repair of single- and double-stranded DNA reduced their defenses against radiation. Further insight into how CAFs communicate with surrounding cancer cells and healthy tissue could prove vital, as it could help researchers and clinicians find ways to topple tumors’ defenses against anticancer therapies..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

The goal of this course is to teach both the fundamentals of nuclear cell biology as well as the methodological and experimental approaches upon which they are based. Lectures and class discussions will cover the background and fundamental findings in a particular area of nuclear cell biology. The assigned readings will provide concrete examples of the experimental approaches and logic used to establish these findings. Some examples of topics include genome and systems biology, transcription, and gene expression.

This activity contains a concept map on DNA replication and repair. These topics are challenging for most undergraduates; thus, this exercise is designed them to give them practice at distinguishing between the enzymes and processes involved.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Our lungs use very fine tissues to exchange oxygen and carbon dioxide between the air and our blood. About 95% of this tissue is made up of a single kind of cell, called type-1 pneumocytes, or AT1 cells. Because they’re so delicate and thin, these cells are vulnerable to damage by pollutants, viruses, and bacteria. Fortunately, lung tissues also have specialized stem cells called AT2 cells that can replace damaged AT1 cells. But exactly how these cube-shaped AT2 cells generate large, flat AT1 cells has remained something of a mystery. To study this problem, the Tata lab in Cell Biology at Duke University has created “mini lungs” inside Petri dishes. They found that inside these “organoids”, the blocky stem cells enter an intermediate state on their way to generating the thin AT1 cells. The stem cells stretch considerably while passing through this transitional state, making them vulnerable to DNA damage. Cells normally pass through that transition within days..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"TRF2 is a protein in charge of protecting the endcaps of chromosomes known as telomeres. But increasing evidence suggests that TRF2 also carries out important non-telomere-related functions, including DNA repair and transcription regulation. To better understand these functions, researchers recently mapped out where else TRF2 sites might exist. ChIP-Seq assays of fibrosarcoma cells revealed extra-telomeric TRF2 sites throughout the genome, which were highly enriched in DNA sequences with the potential to form G-quadruplexes, a DNA structure formed by G-rich sequences with a specific pattern, known to play a critical role in gene expression. TRF2 bound tightly to these sites, and further experiments revealed that TRF2 occupancy resulted in altered mRNA expression in nine target genes. Because naturally occurring intracellular G-quadruplexes are difficult to detect, TRF2 binding may serve as a new tool to specifically detect these regions..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.