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:Explain the processes of digestion and absorptionCompare and contrast different types of digestive systemsExplain the specialized functions of the organs involved in processing food in the bodyDescribe the ways in which organs work together to digest food and absorb nutrients

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:

"Animal health is of utmost importance in the production of milk, meat, and other animal products. Although vitamin supplements can help ensure livestock remain as healthy as possible, they are often expensive, driving up the cost of production. To help reduce these costs, a team of researchers set out to better understand how the essential vitamins B and K₂ are produced by microbes in the gastrointestinal tracts of ruminants, which are animals with complex digestive tracts composed of multiple distinct compartments to help them break down their plant-based diets. The team used genetic data from previous studies to identify 1,135,807 genes and 2366 full genomes involved in B or K₂ vitamin biosynthesis in the gastrointestinal tracts of seven ruminant species. They also found that most of this biosynthesis took place in the stomach compartments rather than other regions and that a high-grain diet enhanced most vitamin biosynthesis but inhibited cobalamin synthesis..."

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:

"Ruminants have long been important in agriculture due to their ability to convert fibrous plant substrates into foods we can digest, like milk and meat. This unique digestive ability is directly tied to their gastrointestinal microbiome, which has made their microbiome a subject of interest to nutritionists, microbiologists, and physiologists. However, most microbiome research to date has focused on the rumen, and we lack a comprehensive map of the microbial diversity throughout their gastrointestinal tract (GIT). A recent study characterized the microbiome across the GIT by sampling 10 GIT regions in 7 ruminant species. In addition to common agricultural species, they sampled water buffalo, yak, roe deer, and water deer. Using this data, they constructed a microbial reference catalog with over 154 million nonredundant genes and over 10,000 metagenome-assembled genomes. They identified 8,745 uncultured candidate species, which encode genes that play key roles in ruminant digestion..."

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:

"As the human population grows, so does the competition for resources between people and livestock. To meet the growing demand for dairy under these conditions, we need to optimize feed efficiency in dairy cattle. In ruminants, feed efficiency is determined by the ability of the rumen, and the microbes within it, to break down complex plant fibers. But the details of how the rumen microbiome contributes to feed efficiency are poorly understood. To close this gap, researchers examined the ruminal metagenomics, metatranscriptomics, and metabolomics of dairy cows with varying feed efficiency. Co-occurrence network analysis revealed that ‘high-efficiency’ animals had stronger and more numerous associations between microbes than animals with low feed efficiency. High-efficiency animals also showed positive interactions between members of the Selenomonas and Succinivibrionaceae bacterial families..."

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

This lecture with slides introduces the functions of ruminant animals, parts and processes of the ruminant digestive system, and details the first two components of the digestive system of ruminant animals. Created by: Arelene Barrett, Dennis Bratton, Mariah Gumphry, Haley Vrazel

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:

"Undernourishment or undernutrition can be caused by a lack of food or a high energy demand, such as during pregnancy and lactation. Undernutrition in production animals disrupts metabolic homeostasis and causes serious health problems, including maternal metabolic disorders and stillbirth. Many production animals are ruminants, named for their unique digestive organ, the rumen, which houses a diverse anaerobic microbiome. The ruminal microbiome allows the host to break down hard-to-digest plant carbohydrates and produce protein that the host later absorbs. But little is known about the effects of undernutrition on the host-microbiome interaction in ruminants. A recent study investigated changes in the ruminal microbiome and epithelium in undernourished pregnant sheep. During undernutrition, the bacterial genes involved in the digestion of carbohydrates and protein synthesis were downregulated. This meant less energy and protein was available to the host and critical signaling pathways were inhibited..."

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