Microorganism virus glossary

An inflammatory disease that may be caused by an untreated or improperly treated case of strep throat. A type of virus that is responsible for causing upper respiratory tract infections in humans, otherwise known as the common cold.

Short for ribonucleic acid, RNA is a molecule with long strands of nucleic acids containing a nitrogenous base, a ribose sugar, and a phosphate. RNA is responsible for controlling a number of chemical activities, including protein synthesis, within cells.

A serious mental illness characterized by the presence of hallucinations, delusions, disorganized speech or thinking, a loss of contact with reality, and a noticeable deterioration of functioning in everyday life. One of the most basic units of biological classification, ranking just below the genus and comprising individuals or populations capable of interbreeding.

The male gamete, or sex cell, which carries the hereditary material of the male parent and unites with the female egg cell during sexual reproduction. An infection caused by any one of several harmful species or subspecies of bacteria of the genus Staphylococcus. The process of destroying all forms of life, including infectious agents, from a surface, fluid, or biological medium with the use of heat, chemicals, irradiation, high pressure, filtration, or some combination of these methods.

A poisonous substance, often a protein, produced by the metabolic processes of living cells or organisms that can cause disease if introduced into the body. The area, sometimes referred to as an ecotone, encompassing the edges of two distinct ecosystems, such as the area where a forest intersects with grassland. An organism usually an arthropod such as a flea, mosquito, or tick that carries an infectious agent from one host to another.

An infectious agent that is only capable of replicating itself inside the living cells of other organisms. A special type of cell that works as part of the immune system to defend the body against disease and infection. The directing and coordinating authority for health within the United Nations system, responsible for providing leadership on global health matters, shaping the health research agenda, setting norms and standards, articulating evidence-based policy options, providing technical support to countries and monitoring and assessing health trends.

A broad group of microscopic fungi that includes harmless forms of yeast used in baking and alcoholic fermentation as well as pathogenic species that can cause disease. Due in large measure to the toll of infectious diseases, the gap in life expectancy between the richest and poorest countries now exceeds how many years? The National Academies. Adaptive Mutation A mechanism through which certain cells can increase the rate in which genetic mutations occur, often in response to stress.

Anemia A condition in which there is a deficit in the number of healthy red blood cells in the blood, resulting in fatigue and feelings of weakness.

Antibiotic Resistance The process through which pathogenic microorganisms, by way of genetic mutation, develop the ability to withstand exposure to the drugs that had once been successful in eradicating them.

Antibiotics A class of drugs used to kill or inhibit the growth of disease-causing microorganisms. Antibodies A class of drugs used to kill or inhibit the growth of disease-causing microorganisms. Autoimmune Disease An umbrella term for a range of conditions in which the immune system mistakenly attacks healthy tissue in the body. Bacilli A taxonomic class of bacteria. Bacteria A large group of unicellular microorganisms that lack a cell nucleus. Beta-lactam Antibiotics One of several families of antibiotics, including penicillins, cephalosporins, carbapenems, and monobactams, containing a molecular ring-shaped structure made up of three carbon atoms and one nitrogen atom.

Biological Agent Terrorism A bacterium, virus, or other biological toxin used in bioterrorism or biological warfare. Bioterrorism The deliberate release of a virus, bacterium, or other biological agent to cause illness and death in people, animals, or plants. Bioweapon A bacterium, virus, or other biological toxin used in bioterrorism or biological warfare. Bronchial Tubes Large tubes that carry air into smaller branches of the lungs after the air has passed through the mouth, nasal passages, and windpipe.

Cancer A class of diseases in which abnormal cells divide without control and are able to invade healthy tissues in various parts of the body. Cell The smallest unit of living matter capable of functioning independently. Cell Membrane A semipermeable barrier that separates the interior of a cell from the external environment.

Chromosome An organized structure of DNA and proteins within the nucleus of a cell that contains many genes. Chronic Disease Any disease that is long lasting 3 months or more or recurrent—as opposed to an acute disease—and cannot be prevented by a vaccine or cured by medication.

Cirrhosis A condition caused by chronic liver disease characterized by the development of scar tissue leading to a loss of liver function. Climate Change The process of shifting from one prevailing state in regional or global climate to another. Chromogenic media. Enteric Bacteria. Gram Stain. Membrane filtration. Sterility test. We use cookies to ensure that we give you the best experience on our website. If you continue to use this site we will assume that you are happy with it.

Read our Privacy Policy for more details. Cilia are shorter than flagella. A scientific study of an intervention in people. The intervention can be a medication, medical device, procedure, or change in behavior.

The goal is to find out if the intervention is safe and effective. In genetics , the process of making many identical copies of a gene or a whole organism. The term also refers to the isolation and manipulation of a gene. A helper molecule either inorganic , such as a metal ion , or organic , such as a vitamin an enzyme needs to work. The random assembly of various chemical units into chemical libraries of new synthetic compounds. The liver can regrow to its original size. A kidney, pancreas, thyroid, adrenal gland, or lung can undergo the same process, but in a more limited way.

This is one type of regeneration. A field of science that uses computers to study complex biological processes that involve many molecular interactions. The narrow beam is forced through a pinhole to keep out-of-focus light from reaching the sample, which increases the resolution without blurriness.

Mirrors move to reflect the beam and guide it across the sample scanning. This technique can visualize structures at different depths in the sample. A process that occurs during meiosis , in which chromosome partners, one inherited from each parent, physically swap sections with one another. This creates hybrid chromosomes that are a patchwork of the original pair.

Crossing over occurs in species that reproduce sexually and increases the genetic variety of offspring. This keeps cellular materials in their normal place.

Cold samples are more stable and can be imaged many times. The cytoplasm within the cell creates a directional flow that pushes around the content of the cells. It includes the cytosol and all organelles except the nucleus. SAHY-toh-SKEL-uh-tuhn A collection of fibers that gives a cell shape and support and allows movement within the cell and, in some cases, by the entire cell.

The three main types of cytoskeletal fibers are actin filaments, intermediate filaments, and microtubules. Actin filaments AK-tin FIL-uh-muhnt Fibers that contract or lengthen to give cells the flexibility to move and change shape. Together with the protein myosin, actin filaments are responsible for muscle contraction. Intermediate filaments Fibers that provide strength in things like nails, hair, the outer layer of skin, nerves, and certain organs.

During cell division, microtubules form the spindle that directs chromosomes to the daughter cells. Microtubules also serve as tracks for transporting vesicles and give structure to flagella and cilia. SAHY-tuh-sol The semi-fluid portion of the cytoplasm , excluding the organelles.

The cytosol is a concentrated solution of proteins , salts, and other molecules. During development, embryonic stem cells differentiate into the many cell types that make up the human body.

Adult stem cells differentiate into the type of tissue in which they are located to replace cells lost to age, disease, or injury.

DIP-loyd A cell or organism that has paired chromosomes , one from each parent. For example, researchers have used distributed computing to study the dynamics of how proteins fold. A long, usually double-stranded chain of nucleotides that carries the information needed for all cellular functions, including protein production.

SEE-kwuhn-sing Sometimes called gene or genome sequencing, a lab technique used to find the exact order of the bases in a DNA molecule. The way a health care provider gives medicine to a person or animal. It usually occurs in the feet, ankles, and legs, but it can involve the entire body. Electrolytes include sodium, calcium, potassium, chlorine, phosphate, and magnesium.

It includes all kinds of radiation, including, in order of increasing energy: radio waves, microwaves, infrared radiation heat , visible light, ultraviolet radiation the part of sunlight that causes sunburn , X-rays, and gamma radiation made by nuclear reactions.

A technique that uses beams of fast-moving electrons instead of light to magnify samples. Powerful magnets focus the electrons into an image. Carbon, hydrogen, and oxygen are fundamental elements in biology.

The cell membrane curves inward, encircling the material, then pinches off, producing a vesicle inside the cell. EN-zahym A biological catalyst that is almost always a protein and speeds up the rate of a specific chemical reaction in the cell.

Eukaryotic cells make up animals, plants, fungi, and some single-celled organisms. In some tissues, it's a thin layer separating cells. In others, it's the major component. The extracellular matrix is most prevalent in connective tissue, the material that forms our skeletons, cushions our internal organs, and winds between blood vessels and around nerves. Sperm and many microorganisms move using flagella.

Researchers use fluorescent dyes to take images of cells. A protein located on the inside of the cell membrane that helps transmit signals from hormones into cells. When the information in a gene directs the building of a protein. The cell reads the gene in groups of three nucleotides. Each of these groups corresponds to one of 20 different amino acids used to build the protein. The instructions in a gene that tell the cell how to make a specific protein.

The scientific study of genes and heredity—of how certain qualities or traits are passed from parents to offspring as a result of changes in DNA sequence. JEE-nohm All of an organism's genetic material. GAWL-jee Also called the Golgi apparatus or Golgi complex; an organelle composed of membranous sacs in which many newly made proteins mature and become functional.

HAP-loid A cell with one copy of each chromosome , as in a sperm or egg. A chemical messenger that affects processes in the body such as growth and development, turning food into energy, sexual function and reproduction, and mood. Hormones are made in one part of the body and travel through the bloodstream to tissues and organs.

Examples include insulin, estrogen, and testosterone. HAHY-druh-kahr-buhn An organic molecule consisting of hydrogen and carbon atoms only. When immune cells, also known as white blood cells, find antigens and prompt the body to make antibodies to fight the infection. Health care providers can use immunotherapy to treat patients with cancer or after an organ transplant, among other uses.

When a gene may be expressed differently in an offspring depending on the sex of the parent who passed on the gene. The body's response to infection or injury, causing redness, swelling, heat, and pain.

A molecule that "inhibits," or blocks, the biological action of another molecule. Opposite of organic. Examples include flies, worms, jellyfish, spiders, clams, and snails. An electrically charged atom. AHY-suh-tohp A form of a chemical element that contains the same number of protons but a different number of neutrons than other forms of the element.

Researchers often use isotopes to trace atoms or molecules in a metabolic pathway. Any of a diverse group of organic compounds that don't dissolve in water. Lipids include fats, oils, hormones , and certain parts of cell membranes. LAHY-puh-sohm An oily, microscopic capsule designed to package and deliver biological cargo, such as drugs, to cells in the body. LAHY-suh-sohm A bubblelike organelle that contains powerful enzymes that break apart biological materials into nutrients and building blocks.

Lysosomes also break apart waste and transport the waste to the outside of the cell. An approach to artificial intelligence in which a computer algorithm a set of rules and procedures is developed to analyze and make predictions from data that is fed into the system. Machine learning-based technologies are routinely used every day, such as personalized news feeds and traffic prediction maps.

Typical applications include dating of geologic samples; analysis of inorganic and organic chemicals, especially for small amounts of impurities; and determining the structural formula of complex organic substances. An area of study involved with designing and making medicines for use in humans and animals.

Meiosis generates cells that are genetically different from one another and contain half the total number of chromosomes in the parent cell. The other type of cell division is mitosis. A semi-fluid layer of lipids and proteins. Membranes enclose cells and organelles and control passage of materials into and out of them. A technology used to study the expression of many genes at once. A scientist places thousands of gene sequences in known locations on a glass slide called a gene chip.

Light is produced to show genes expressed in the sample. An organism that can be seen only with the aid of a microscope and is usually just a single cell. Mitochondria contain their own small genomes and appear to have descended from free-living bacteria. Mitosis results in two daughter cells that are genetically identical to the parent cell. The other type of cell division is meiosis. A small group of research organisms that help us understand the biology of humans.

Examples include yeast, fruit flies, worms, zebrafish, and mice. The molecule researchers design a drug to bind to, producing therapeutic effects. These molecules are called receptors, and the drug can be an agonist that activates the receptor or an antagonist that blocks the receptor. The smallest unit of matter that retains all of the physical and chemical properties of that substance.

It consists of one or more identical atoms or a group of different atoms bonded together. For example, a water molecule contains two hydrogen atoms and one oxygen atom. Mutations can be caused by mistakes during cell division, exposure to some types of radiation or chemicals, or viral infections. Mutations in egg or sperm cells can be passed on to offspring, while mutations in body cells aren't passed on.

MAHY-uh-lin A fatty covering that protects nerve fibers and makes nerve signals move quickly through the nervous system. NAN-uh-tek-nol-uh-jee Study of the control of matter on an atomic and molecular scale. A nanometer is one-billionth of a meter, or about the circumference of a marble in comparison to that of the Earth. Researchers can use nanotechnology across many fields of science, such as chemistry , biology, physics, and materials science.

A molecule produced by a living organism —a plant, marine organism, or microorganism —that often has a medicinal use. The other type of cell death is called apoptosis. A type of stem cell. Neoblasts are found throughout the planarian worm anatomy and are responsible for regeneration.

A cell in the nervous system that carries information through electrical impulses and chemical messengers.