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:Describe endocytosis, including phagocytosis, pinocytosis, and receptor-mediated endocytosisUnderstand the process of exocytosis

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:

"White spot syndrome virus (WSSV) is the most destructive virus in crustacean aquaculture, causing huge economic losses. Preventing the initial entry of the virus into host cells is likely the most economical way to control WSSV infection. However, the exact mechanism of virus invasion isn’t clear. To learn more, researchers recently investigated how WSSV evades the host immune system in the crayfish Procambrus clarkii. They found that the enzyme TRIM was significantly upregulated in WSSV-infected crayfish. A recombinant TRIM protein inhibited WSSV replication in the crayfish, while blocking TRIM promoted it, suggesting that this enzyme plays a protective role. Further experiments revealed that TRIM interacts with the viral protein VP26. This interaction keeps the host protein AP-1 from entering the nucleus and driving the expression of dynamin. Without dynamin, WSSV can’t enter the host cell via membrane vesicles..."

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:

"Malignant gliomas are the most common and the deadliest type of tumor affecting the central nervous system. Even after surgery, chemotherapy, and radiotherapy, gliomas can still have a poor prognosis. But growing evidence is pointing to one promising target for fighting glioma. Exosomes are tiny sacs of cellular matter implicated in numerous cell processes. including signaling and communication and glioma progression. miRNAs are among the most important glioma-related payloads shuttled between cells by exosomes. In addition to increasing the risk of developing glioma. miRNAs can confer chemotherapy drug resistance from one cell to another or they can even help inhibit glioma tumor growth. Researchers are discovering that exosomal proteins may play similar roles. Understanding how exosomes operate and how they might be manipulated. could help researchers and clinicians deliver more powerful anti-cancer therapies to patients with glioma..."

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:

"In endocytosis, the cell plasma membrane folds inward and pinches off to form intracellular vesicles. Originally, endocytosis was thought to primarily facilitate feeding and pathogen neutralization, but it is now known to regulate numerous processes in eukaryotic cells, such as signaling, membrane composition, mitosis, movement, and morphogenesis. Endocytosis also plays many roles in T cells through both clathrin-dependent and clathrin-independent mechanisms. For example, clathrin-mediated endocytosis regulates the receptors on the plasma membrane and internalizes α/β-type T cell antigen receptors (TCRs). Through clathrin-independent pathways, endocytosis internalizes TCRζ and the IL-2Rβ complex and recycles TCRαβ. Clathrin-independent endocytosis also helps T cells bind to antigen-presenting cells of the immune system and ingest pathogens and other foreign materials to aid in host defense and immune surveillance..."

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:

"Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer. One of the distinguishing features of HCC tumors is their dense network of blood vessels. This makes Angiopoetin-2, a protein that promotes vessel formation in tumors, an attractive target for fighting HCC. In a recent study, researchers discovered a novel route HCC tumors use to release Angiopoetin-2. Test-tube experiments revealed that tumor cells wrapped Angiopoetin-2 in tiny sacs called exosomes. and delivered them to cells derived from human umbilical cord, which boosted blood vessel formation. Gene editing allowed the team to knock out the gene controlling Angiopoetin-2, which, once delivered, significantly reduced the generation of new lifelines from healthy cells. The results point to a new way of disrupting tumor growth. and could lead to new therapies for cancer of the liver and other organs..."

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:

"Lymphotoxin β receptor (LTβR) is a key regulator of the immune response. Its signaling cascades control the development and maintenance of secondary lymphoid organs and immune cell development. Although many aspects of its signaling have been characterized, one important aspect remains unclear. After ligand binding, LTβR is internalized via endocytosis – but the precise mechanisms involved have not yet been characterized. A recent study investigated the contribution of LTβR internalization to its signaling potential. Researchers found LTβR localized to endocytic vesicles and the Golgi apparatus. After ligand binding, LTβR was trafficked via endosomes to lysosomes for degradation, downregulating signaling. Multiple entry pathways – clathrin-mediated, dynamin-dependent, and clathrin-independent – were used for receptor internalization, and without clathrin and dynamin, cells had elevated signaling through the NF-κB pathway..."

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:

"Extracellular vesicles (EVs) are released by all cells, and they regulate intercellular communication in health and disease. A subset of EVs, exosomes, play significant roles in cellular communication and influence a broad range of physiological processes. Exosomes have gained increasing attention in clinical setting due to their ability to transfer cargoes, including signalling mediators, to recipient cells. Exosomes – defined as membrane-bound EVs 30-200 nm in size – originate from multivesicular bodies (MVBs), a specialised endosomal compartment rich in intraluminal vesicles (ILVs). The process of forming ILVs and secreting their contents at the plasma membrane depends on the combined function of a variety of cellular components. Exosomes can trigger signalling in target cells either by direct interaction with extracellular receptors or by fusing with the plasma membrane or internalisation of exosome contents can occur through a variety of pathways..."

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