An atom is electrically neutral because it has equal numbers of protons and electrons; an ion is an atom or group of atoms with a net electric charge because it has gained or lost electrons. The key difference is electron balance: forming an ion usually changes the number of electrons, while the number of protons […]

An amino acid is a small molecule that can serve as a building block of a protein; a protein is a larger molecule made from one or more chains of amino acids folded into a particular shape. Put simply, amino acids are the components, while proteins are assembled structures whose sequence and shape help determine

An acid donates protons (hydrogen ions) in the Brønsted–Lowry model, while a base accepts them; in the Lewis model, an acid accepts an electron pair and a base donates one. These definitions describe related but not identical behaviors, so the useful distinction depends on the reaction being studied. What Is an Acid? In water, an

In college, “UG” usually stands for “undergraduate.” It describes a student who is working toward a first college degree, such as an associate degree or a bachelor’s degree, or it labels programs and services intended for those students. What “undergraduate” means Undergraduate study is the level of education that generally comes before graduate study. A

On a college or university transcript, “U” most commonly means “unsatisfactory” or “ungraded,” but its exact meaning depends on the institution and the course. It may indicate an outcome in a pass/fail or satisfactory/unsatisfactory system, or it may be a special notation rather than a letter grade, so check the transcript legend and your school’s

At university, a tutorial is a small-group teaching session that helps students explore course material through discussion, questions, and problem-solving. It usually supports a lecture or other course work; its exact format, size, attendance rules, and grading role depend on the course and university. What a university tutorial is A tutorial is a scheduled class

In a university, a trimester is an academic calendar divided into three main study periods, or terms, within an academic year. Each term is a defined stretch of teaching and assessment, and students usually take courses in one term at a time; the exact dates, course load, and breaks depend on the institution. What a

In a university, tenure is a continuing faculty appointment that gives a professor substantial job security after a formal review. It is intended to protect academic freedom and support long-term teaching, research, and service—not to guarantee a promotion, a particular salary, or immunity from every form of dismissal. What tenure means Tenure is a status

In college, a syllabus is the course document that explains what a class covers, how it is organized, and what students are expected to do. It commonly describes assignments, grading, course materials, class policies, and ways to contact the instructor, giving students a practical guide for the term. What a college syllabus is for A

In college, STEM stands for science, technology, engineering, and mathematics. It is a broad label for academic fields that use scientific inquiry, quantitative reasoning, technical methods, or a combination of them—not the name of one specific major or a single standard college program. What the STEM label means Colleges use STEM as an umbrella term