A microscopic single-celled organism having no distinguishable nucleus, belonging to the kingdom Monera. Bacteria have varying shapes, usually taking the form of a jointed rodlike filament, or a small sphere, but also in certain cases having a branched form. Bacteria are destitute of chlorophyll, but in those members of the phylum Cyanophyta (the blue-green algae) other light-absorbing pigments are present. They are the smallest of microscopic organisms which have their own metabolic processes carried on within cell membranes, viruses being smaller but not capable of living freely. The bacteria are very widely diffused in nature, and multiply with marvelous rapidity, both by fission and by spores. Bacteria may require oxygen for their energy-producing metabolism, and these are called aerobes; or may multiply in the absence of oxygen, these forms being anaerobes. Certain species are active agents in fermentation, while others appear to be the cause of certain infectious diseases. The branch of science with studies bacteria is bacteriology, being a division of microbiology. See Bacillus.
(bacteria) See germ
a tiny, single-celled microorganism, commonly known as a germ; some bacteria, called pathogens, cause disease
(bak-TEER-ee-um) ( listen) Single-celled, often parasitic microorganism without distinct nuclei or organized cell structures. Various species are responsible for decay, fermentation, nitrogen fixation, and many plant and animal diseases. Plural: bacteria (bak-TEER-ee-uh).
A form of life that is usually one cell and can be seen only with a microscope. There are many different kinds of bacteria and they are the oldest type of life on Earth.
microscopic one-celled organisms that are the cause of many diseases.
One-celled organism without a nucleus that reproduces by cell division; can infect humans, plants, or animals.
A single-celled microscopic organism. Bacteria live in dirt and water, or in plants and animals. Some bacteria aid digestion, while others can cause diseases like pneumonia, diphtheria, and tuberculosis. They can be round, rod-shaped or spiral. Vaccinations help increase immunity to some of the diseases bacteria carry while antibiotics can fight others.
Common name for any member of the diverse group of procaryotic organisms. Most are single cells, but multicellular forms also exist.
(plural: bacteria) unicellular microscopic prokaryote, also called moneran
Any of numerous unicellular microorganisms of the class Schizomycetes, occurring in a wide variety of forms, existing either as free-living organisms or as parasites, and having a wide range of biochemical, often pathogenic, properties.
a single-celled, microscopic organism that reproduces by cell division, usually has a cell wall, and has no distinct cellular nucleus; some bacteria cause disease, whereas others are beneficial (aiding in digestion, for example).
living microorganism less than a few micrometres in size, that is generally single cell, without a nucleus and able to multiply quickly
a microorganism that is a single cell. Bacteria have a cell wall and multiply by cell division.
A microscopic organism that can exist in many forms. They can thrive by themselves in the environment or act as parasites (that is, using other organisms for nourishment).
pl. bacteria A prokaryotic microorganism in Domain Bacteria. balanced polymorphism A type of polymorphism in which the frequencies of the coexisting forms do not change noticeably over many generations. bark All tissues external to the vascular cambium in a plant growing in thickness, consisting of phloem, phelloderm, cork cambium, and cork. Barr body A dense object lying along the inside of the nuclear envelope in female mammalian cells, representing an inactivated X chromosome. basal body[Gk. basis, foundation] A eukaryotic cell organelle consisting of a 9 + 0 arrangement of microtubule triplets; may organize the microtubule assembly of a cilium or flagellum; structurally identical to a centriole.
Any of an extremely flexible class of microscopic life whose members have a variety of structures, come singly or in colonies, live just about anywhere, and derive energy from whatever source is available.
(microbiology) single-celled or noncellular spherical or spiral or rod-shaped organisms lacking chlorophyll that reproduce by fission; important as pathogens and for biochemical properties; taxonomy is difficult; often considered plants
a cell membrane filled with a variety of molecules
a living, reproducing lifeform
a microscopic chemical factory producing antibiotics, immunosuppressants, and anticancer drugs no chemist can synthesize, according to chemical engineer Camilla Kao
a prokaryotic cell The simplest and most primitive of cells are the prokaryotic cells (pro means before and caryon refers to the nucleus)
a prokaryotic cell with its own circular DNA
a self-contained cell about one-hundredth the size of a human cell
a single-cell microorganism
a tiny, primitive cell without a nucleus Bacterial cells has cell walls as do plant cells
a very small organism made up of one cell
a single bacterial organism.
a microscopic organism that causes infection.
A microscopic unicellular organism that lacks a nuclear membrane. Some can cause disease.
a microscopic organism, in this case, one which infects insect larvae causing them to become ill and die.
Tiny, one-celled organism that reproduces by cell division and can be found in virtually any environment
microscopic single-celled organism, which may or may not be a pathogen.
A simple prokaryotic microorganism having absorptive nutrition.
A single-celled prokaryotic microorganism. Many bacteria cause disease.
(plural = bacteria) a microorganism lacking a nucleus and genetically distinct from plants, animals, fungi and protists.
A single-celled organism (singular of bacteria). Bacteria are classified according to shape or whether they need oxygen or not.
(pl. Bacteria ) - Microscopic one-celled organism. Cell type lacks a distinct nucleus, sexual recombination, and chlorophyll. It does have cell walls and DNA.
A single-celled, microscopic organism without a distinct nucleus.
Any of a large group of microscopic organisms with a very simple cell structure. Some manufacture their own food, some live as parasites on other organisms, and some live on decaying matter. (See Prokaryote)
a single celled microscopic organism, whose genetic material is not enclosed by a membrane.
a simple single-celled microorganism. Bacteria are classified by their shape (e.g., rod, spirochete), staining properties (Gram positive or Gram negative) and habitat (aerobic, anaerobic). Many types of bacteria are pathogenic in humans.
A primitive, one-celled microorganism without a nucleus. Bacteria live almost everywhere in the environment. Some bacteria may infect humans, plants, or animals. They may be harmless or they may cause disease.
a class of microorganisms that are made of a single cell with a certain structure. While many bacteria are beneficial, some bacteria can cause disease. (plural, bacteria)
(Gr. bakterion, a stick; pl: bacteria) Common name for the class Schizomycetes: minute (0.5-5 m), unicellular organisms, without a distinct nucleus. Bacteria are prokaryotes, and most of them are identified by means of Gram staining (q.v.). They are classified on the basis of their oxygen requirement (aerobic vs anaerobic) and shape (spherical = coccus; rodlike = bacillus; spiral = spirillum; comma-shaped = vibrio; corkscrew-shaped = spirochaete; filamentous). Bacteria usually reproduce asexually, by simple cell division, although a few undergo a form of sexual reproduction, termed conjugation. A few bacteria can photosynthesize (including green-blue cyanobacteria), some are saprophytes and others are parasites and can cause diseases. They are major agents of fermentation, putrefaction and decay, and frequently a source of contamination in tissue culture. In plant pathology, strains of bacteria causing disease in specific plant cultivars are called pathovars (q.v.).
single-celled microorganisms that live in soil, water, organic matter, or the bodies of plants and animals.
(Pl. bacteria). a single-celled, microscopic, plantlike organism that lacks a nucleus. Most bacteria obtain their nitrogen and energy from organic matter; some bacteria cause plant or animal diseases.
Germ which can enter the body and cause an infection or illness. Infections caused by bacteria can usually be cured with antibiotics. Some STDs caused by bacteria include gonorrhea, syphilis, and chlamydia.
A microscopic organism composed of a single cell can cause diseases.
Français] A single-cell organism that has no nucleus.
A microscopic organism composed of a single cell. Many but no all bacteria cause disease.
single celled micro-organisms. Some bacteria are neccessary for our bodies to work properly. Other bacteria cause disease.
a group of small, single-celled, prokaryotic microorganisms that can live as a parasite (survival depends on another organism) or as an independent life form. Bacteria can vary in size and shape (rod, sphere, spiral, etc.), reproduce by cellular division, and utilize different forms of motility. Their nutritional sources also vary widely, as bacteria can live off of organic or inorganic sources and can live with or without oxygen present. The ability for bacteria to adapt to different environments and food sources allow them to survive in practically any location. [Source: Biotechnology Industry Organization, www.bio.org
A one-celled microorganism that contains no nucleus.
The traditional name for a single-celled prokaryotic organism of microscopic size. Bacteria are ubiquitous in the environment, inhabiting water, soil, organic matter, and the bodies of plants and animals. Recent taxonomic restructuring of the prokaryotes has divided them into two distinct lines of evolutionary descent, the domains Archaea and Bacteria.
A single celled micro-organism which is able to multiply by itself, rather than by using the cellular machinery of its host (see virus). Bacteria are normally found all over a healthy body (e.g. skin, mouth, gut) but can cause disease by invading previously sterile sites (e.g. blood or spinal fluid) or by invading locally into the tissues where they enter the body (e.g. nose, throat). Bacteria are classified according to their shape and structure.
Single cell micro-organisms, some of which cause disease. Others are essential for our bodies to work properly.
Minute living organisms which are neither animals nor plants. Bacteria is a plural word, the singular is bacterium. Newspaper reporters commonly, but wrongly, use the plural (bacteria) as if it were singular. There are large numbers of species. Some bacteria are entomopathogens.
A microscopic single-celled organism which can be both beneficial, as in a biological filter system, or troublesome, as with a number of bacterial fish diseases.
singular form of the word bacteria.
(pl.: bacteria) Nicellular prokaryotic organisms, without a distinct nucleus. Major distinctive groups are defined by Gram staining. Also classified on the basis of oxygen requirement (aerobic vs anaerobic) and shape (spherical = coccus; rodlike = bacillus; spiral = spirillum; comma-shaped = vibrio; corkscrew-shaped = spirochaete; filamentous).
The singular form of bacteria.
A very common single cell micro-organism which is very small and typically around one micron in diameter. Individual cells may be spherical, straight or curved rods, or spirals. They may have capsules or they may have whip-like appendages (flagella) which help them to move. Some bacteria cause disease in man or animals (pathogenic), while others are harmless (non-pathogenic) and exist in man where they help many of the body's processes such as digestion in the gut.
microscopic, single-celled organisms found in virtually any environment, usually less than one micrometer (one-thousandth of a millimeter) in length. A single bacterium divides to form two new bacteria containing an exact copy of the genetic information of the parent cell. Typical forms include rod-shaped (bacillus), round (coccus), and spiral (spirillum).
Class of single-cell organisms (plural, bacteria). One member, E. coli, is commonly used in recombinant DNA technology for producing proteins and other chemicals.
A bacterium (plural bacteria) is a microscopic, prokaryotic, single-celled organism with a cell wall. Bacteria reproduce by binary fission. Bacteria are one ot the earliest forms of life. Some bacteria ( rhizobia) are nitrogen-fixing; they transform nitrogen gas in the atmopshere into a form that can be used by plants.
Any of a class ( Schizomycetes) of microscopic plants having round, rodlike, spiral, or filamentous single-celled or noncellular bodies often aggregated into colonies or motile by means of flagella, living in soil, water, organic matter, or the bodies of plants and animals, and being autotrophic, saprophytic, or parasitic in nutrition and important to man because of their chemical effects and as pathagens.
Any microorganism of the class Schizomycetes; composed of several structures, including a nucleus, cytoplasm and cytoplasmic membrane, cell wall, and capsule. Motile forms may have flagella. Some of these one-celled organisms cause diseases.