This glossary provides pronunciations and easy-to-understand definitions for terms commonly used in basic biomedical research. To search the glossary, enter the word or term you’re looking for and the terms and definitions containing the word(s) will appear below. Search results are refined with each letter entered. You can also use your browser’s “find” feature.
A pure substance that can't be chemically separated into simpler substances. Carbon, hydrogen, and oxygen are fundamental elements in biology.
The body's response to infection or injury, causing redness, swelling, heat, and pain.
The group of animals that don’t have a backbone. Examples include flies, worms, jellyfish, spiders, clams, and snails.
An area of study involved with designing and making medicines for use in humans and animals.
Molecular describes things related to, consisting of, or produced by molecules.
A molecule produced by a living organism—a plant, marine organism, or microorganism—that often has a medicinal use.
A cell in the nervous system that carries information through electrical impulses and chemical messengers. Also called a neuron.
Non-steroidal anti-inflammatory drug, such as aspirin or ibuprofen, that reduces pain and inflammation.
A group of cells and tissues that perform a specific job, including the heart, brain, kidneys, liver, and lung.
Carbon-containing compounds that are the basis for all living organisms. Opposite of inorganic.
An individual animal, plant, or single-celled life form.
A natural process where green plants, algae, and some bacteria use the sun's energy to make carbohydrates from carbon dioxide and water. The carbohydrates are then broken down to produce energy, allowing the plant to grow.
A serious injury to the body, such as the following:
Surgery can also cause physical trauma, sometimes called a controlled injury.
A double layer of phospholipids with embedded proteins that separates the contents of a cell from its outside environment.
An emerging approach for disease prevention and treatment that takes into account individual differences in lifestyle, environment, and biology.
A large, biological molecule composed of amino acids. Proteins are essential for all life processes. They are arranged in a specific order determined by the genetic code and folded into a specific three-dimensional shape with well-defined structures. Protein structures include alpha helixes, short, spiral-shaped sections, and beta sheets, pleated sections.
The process the body uses to create proteins from amino acids in the cell’s ribosomes.
A protein found on the cell surface to which a signal molecule attaches. This leads to a cascade of reactions involving several other molecules inside the cell. Specific signal molecules bind to specific receptors, fitting together like a key in a lock. Many medicines target receptor proteins, either triggering a response (agonist) or preventing a response (antagonist).
Regeneration is the natural process of replacing or restoring damaged or missing cells, tissues, organs, and even entire body parts to full function in plants and animals.
Any creature that scientists use to study life. Examples range from single-celled organisms such as bacteria to more complex ones such as mice.
Certain viruses contain RNA, instead of DNA, as their genetic material.
When noncoding pieces of RNA, called introns, are removed and coding pieces of RNA, called exons, are joined together to produce an mRNA molecule.
A naturally occurring process in which small pieces of double-stranded RNA are used to prevent translation of messenger RNA. The process occurs in many organisms to silence genes when their protein products are no longer needed. When RNAi doesn’t work as it should, it may lead to certain diseases. RNAi has an important role in basic research allowing scientists to directly observe the effects of the loss of function of specific genes.
A serious medical condition caused by an overwhelming immune response to infection. The body releases immune chemicals into the blood to combat the infection. Those chemicals trigger widespread inflammation, which leads to blood clots and leaky blood vessels. As a result, blood flow is impaired, depriving organs of nutrients and oxygen and leading to organ damage. There are four levels of sepsis:
The effect of a drug, other than the desired effect, sometimes in an organ other than the target organ.
A cell that can develop into many different cell types in the body. When stem cells divide, they can form more stem cells or other specialized cells.
The study of how biological molecules are built. Imaging techniques allow scientists to view molecules in three dimensions to see how they are put together, how they function, and how they interact.
A molecule that binds to an enzyme and undergoes a chemical change during the ensuing reaction.
The science of the formation of more complex chemical molecules from simpler building blocks.
A field focused on the study of relationships and interactions between various parts of a biological system (metabolic pathways, organelles, cells, and organisms) and that integrates this information to understand how biological systems function.
A group of cells that act together to carry out a specific function in the body. Examples include muscle tissue, nervous system tissue (including the brain, spinal cord, and nerves), and connective tissue (including ligaments, tendons, bones, and fat). Organs are made up of tissues.
A field of study that combines cells, engineering, and materials methods, with the goal of improving or replacing biological functions.
The most powerful type of electron microscopy (EM), which uses electrons to create an image of a sample. TEM can magnify objects more than 10 million times, making the outline and some details of cells, viruses, and even some large molecules visible.
The group of animals that have a spine/backbone inside their body. Examples include mammals, fish, reptiles, and birds.
An infectious agent composed of proteins and genetic material (either DNA or RNA) that requires being in a host cell, such as a plant, animal, or bacterium, in order to reproduce. A virus is neither a cell nor a living organism because it can't reproduce on its own.
This page last reviewed on 3/27/2020 9:22 AM
