The anus is the terminal portion of the alimentary tract which communicates with the external environment. Two sphincters control it's aperture. It allows faeces and gas to leave the body. Defeacation is the process where faeces are expelled from the rectum through the anus.

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:

Describe the process of digestion
Detail the steps involved in digestion and absorption
Define elimination
Explain the role of both the small and large intestines in absorption

Different hormones, neurotransmitters and reflexes are involved in the complicated process of feeding in animals. Secretions and motility of the gastrointestinal tract are stimulated and carefully regulated by numerous factors, including environmental stimuli and the presence of food in different parts of the gastrointestinal tract from the oral cavity right through to the intestines. When a harmful substance is ingested the body acts to eliminate it in different ways to prevent the animal becoming ill, for example, through vomiting and diarrhoea. If one or more of the pathways in controlling feeding is damaged or inhibited, then problems such as obesity occurs.

In this lab, the student will review the physiology of the organ systems by using images of models, experiments, and videos. Then the student will be asked to assess his or her knowledge, which can eventually be put to practical or experimental use. Upon successful completion of this lab supplement, students will be able to: describe techniques used to measure the function of organ systems; relate diagnostic tools, such as those used to measure ECG, EEG, and EMG activity, and those used in spirometry and urinalysis tests, to the physiological processes; relate diagnostic tests, such as the patellar and plantar reflex tests, to physiological processes; perform laboratory observations and experiments; collect, analyze, and interpret data; and form conclusions. (Biology 304 Laboratory)

The Kansas State University Human Nutrition (FNDH 400) Flexbook is a textbook for students taking Kansas State University FNDH 400 course.FNDH 400 is a 3-hour, intermediate-level, human nutrition course at Kansas State University take primarily by sophomores and juniors because it has prerequisites of a college biology and chemistry courses.

Table of Contents
Chapter 1: Nutrition Basics
Chapter 2: Macronutrient Structures
Chapter 3: Macronutrient Digestion
Chapter 4: Macronutrient Uptake, Absorption, & Transport
Chapter 5: Common Digestive Problems
Chapter 6: Macronutrient Metabolism
Chapter 7: Integration of Macronutrient Metabolism
Chapter 8: Micronutrients Overview & Dietary Reference Intakes (DRIs)
Chapter 9: Antioxidant micronutrients
Chapter 10: Macronutrient Metabolism Micronutrients
Chapter 11: One-Carbon Metabolism Micronutrients
Chapter 12: Blood, Bones & Teeth Micronutrients
Chapter 13: Electrolyte Micronutrients