Biology, SUR-URE
How do plants feed themselves? How did dogs evolve from wolves? What good is the appendix in humans, anyway? Such questions fall within the domain of biology, which seeks to understand living organisms and their vital processes (although the jury’s still out on what our appendixes are for). Biology’s diverse fields include botany, ecology, evolution, genetics, medicine, physiology, and zoology.
Biology Encyclopedia Articles By Title
survival of the fittest, term made famous in the fifth edition (published in 1869) of On the Origin of Species......
swallowing, the act of passing food from the mouth, by way of the pharynx (or throat) and esophagus, to the stomach.......
sweat, the moisture excreted in visible quantities through the openings of the sweat glands. See...
sweating sickness, a disease of unknown cause that appeared in England as an epidemic on five occasions—in 1485,......
swine flu, a respiratory disease of pigs that is caused by an influenza virus. The first flu virus isolated from......
Sydenham chorea, a neurological disorder characterized by irregular and involuntary movements of muscle groups......
synapse, the site of transmission of electric nerve impulses between two nerve cells (neurons) or between a neuron......
syncope, effect of temporary impairment of blood circulation to a part of the body. The term is most often used......
synovial tissue, thin, loose vascular connective tissue that makes up the membranes surrounding joints and the......
synthetic biology, field of research in which the main objective is to create fully operational biological systems......
syringomyelia, chronic, progressive disease characterized principally by the development of a cyst, called a syrinx,......
syrinx, vocal organ of birds, located at the base of the windpipe (trachea), where the trachea divides into the......
systemic circulation, in physiology, the circuit of vessels supplying oxygenated blood to and returning deoxygenated......
systems biology, the study of the interactions and behaviour of the components of biological entities, including......
systems ecology, Branch of ecosystem ecology (the study of energy budgets, biogeochemical cycles, and feeding and......
systole, period of contraction of the ventricles of the heart that occurs between the first and second heart sounds......
Although his formal education occurred between the ages of 8 and 10, plus four or five years at medical school,......
target theory, in biology, the concept that the biological effects of radiations such as X rays result from ionization......
taste, the detection and identification by the sensory system of dissolved chemicals placed in contact with some......
taste bud, small organ located on the tongue in terrestrial vertebrates that functions in the perception of taste.......
taxidermy, the practice of creating lifelike representations of animals, most commonly birds and mammals, by the......
taxon, any unit used in the science of biological classification, or taxonomy. Taxa are arranged in a hierarchy......
taxonomy, in a broad sense the science of classification, but more strictly the classification of living and extinct......
- Introduction
- Linnaean System, Classification, Naming
- Classification, Linnaeus, Systematics
- Classification, Naming, Organizing
- Ranks, Species, Classification
- Naming, Classification, Systematization
- Evaluating, Characters, Classification
- Classification, Naming, Categorizing
- Classification, Naming, Organizing
- Classification, Organisms, Groups
Tay-Sachs disease, hereditary metabolic disorder that causes progressive mental and neurologic deterioration and......
tear duct and glands, structures that produce and distribute the watery component of the tear film. Tears consist......
teliospore, in fungi (kingdom Fungi), a thick-walled, winter or resting spore of rust fungi (phylum Basidiomycota)......
telomere, segment of DNA occurring at the ends of chromosomes in eukaryotic cells (cells containing a clearly defined......
telophase, in mitosis and meiosis, the final stage of cell division in which the spindle disappears and the nucleus......
telosporidian, any spore-forming protozoan of the class Telospora (sometimes called Telosporida), characterized......
tendon, tissue that attaches a muscle to other body parts, usually bones. Tendons are the connective tissues that......
teratology, branch of the biological sciences dealing with the causes, development, description, and classification......
teratoma, rare tumor that originates from remnants of germ cells (the precursors of eggs and sperm) or germ layers......
testcross, the mating of an organism whose genetic constitution is unknown with an organism whose entire genetic......
testis, in animals, the organ that produces sperm, the male reproductive cell, and androgens, the male hormones.......
testosterone, hormone produced by the male testis that is responsible for development of the male sex organs and......
Abraham Lincoln and Charles Darwin, two of the 19th century’s most enduring thinkers and figures, share more than......
theileriasis, any of a group of livestock diseases caused by protozoan parasites of the genus Theileria (Gonderia),......
thermoperiodicity, the growth or flowering responses of plants to alternation of warm and cool periods. Daily temperature......
Thermoplasma, (genus Thermoplasma), any of a group of prokaryotic organisms (organisms whose cells lack a defined......
thermoreception, sensory process by which different levels of heat energy (temperatures) in the environment and......
thermoregulation, the maintenance of an optimum temperature range by an organism. Cold-blooded animals (poikilotherms)......
thoracic outlet syndrome (TOS), name given for a spectrum of symptoms caused by compression of the brachial nerve......
thoracic squeeze, compression of the lungs and thoracic (chest) cavity that occurs during a breath-holding dive......
three-parent baby, human offspring produced from the genetic material of one man and two women through the use......
thrombocyte, a small, nucleated, spindle-shaped cell of nonmammalian vertebrates that plays a role in the clotting......
thrombocytopathy, any of several blood disorders characterized by dysfunctional platelets (thrombocytes), which......
thrombocytopenia, abnormally low number of platelets (thrombocytes) in the circulation. Normal platelet counts......
thrombosis, formation of a blood clot in the heart or in a blood vessel. Factors that play a role in the formation......
thymus, pyramid-shaped lymphoid organ that, in humans, is immediately beneath the sternum (breastbone) at the level......
thyroid gland, endocrine gland that is located in the anterior part of the lower neck, below the larynx (voice......
thyroid tumour, any of various benign tumours (adenomas) or malignant tumours (cancers) of the thyroid gland. Thyroid......
tinnitus, ringing or buzzing in the ears. An estimated one-third of adults experience tinnitus at some point in......
tissue, in physiology, a level of organization in multicellular organisms; it consists of a group of structurally......
tissue culture, a method of biological research in which fragments of tissue from an animal or plant are transferred......
toadstool, any of various inedible or poisonous species of mushrooms (kingdom Fungi). See...
togavirus, any of three genera of arthropod-borne viruses (arboviruses) of the family Togaviridae. Flaviviruses,......
tongue-tie, congenital shortening of the flap of mucous membrane (frenum) beneath the tongue, a condition that......
tonsillitis, inflammatory infection of the tonsils caused by invasion of the mucous membrane by microorganisms,......
torpor, a state of lowered body temperature and metabolic activity assumed by many animals in response to adverse......
Tourette syndrome, rare inherited neurological disorder characterized by recurrent motor and phonic tics (involuntary......
toxemia of pregnancy, term formerly used to describe hypertensive conditions that can be induced by pregnancy.......
toxicological examination, medical inspection of an individual who is, or is suspected of being, poisoned. In most......
toxicology, study of poisons and their effects, particularly on living systems. Because many substances are known......
toxicology test, any of a group of laboratory analyses that are used to determine the presence of poisons and other......
toxoplasmosis, infection of cells of the central nervous system, spleen, liver, and other organs by a parasite,......
trace element, in biology, any chemical element required by living organisms in minute amounts (that is less than......
trachea, in vertebrates and invertebrates, a tube or system of tubes that carries air. In insects, a few land arachnids,......
trachoma, chronic inflammatory disease of the eye caused by Chlamydia trachomatis, a bacterium-like microorganism......
transfection, technique used to insert foreign nucleic acid (DNA or RNA) into a cell, typically with the intention......
transfer RNA (tRNA), small molecule in cells that carries amino acids to organelles called ribosomes, where they......
transferrin, protein (beta1 globulin) in blood plasma that transports iron from the tissues and bloodstream to......
transformation, in biology, one of several processes by which genetic material in the form of “naked” deoxyribonucleic......
translation, the synthesis of protein from RNA. Hereditary information is contained in the nucleotide sequence......
trapezius muscle, large, superficial muscle at the back of the neck and the upper part of the thorax, or chest.......
traumatic brain injury, any damage to the brain from an applied force. The forces involved can be from direct contact,......
triceps muscle, any muscle with three heads, or points of origin, particularly the large extensor along the back......
trichinosis, disorder resulting from infestation with roundworms of genus Trichinella, especially the small roundworm......
trichocyst, a structure in the cortex of certain ciliate and flagellate protozoans consisting of a cavity and long,......
trichomonad, any protozoan of the zooflagellate order Trichomonadida. Trichomonads have three to six flagella,......
Trichophyton, a genus of fungi in order Onygenales (phylum Ascomycota, kingdom Fungi) that infects the skin, hair,......
tropism, response or orientation of a plant or certain lower animals to a stimulus that acts with greater intensity......
truffle, (genus Tuber), edible subterranean fungus, prized as a food delicacy. True truffles are in the genus Tuber......
trypanosomiasis, infectious disease in both humans and animals caused by certain members of the flagellate protozoa......
tuberculosis (TB), infectious disease that is caused by the tubercle bacillus, Mycobacterium tuberculosis. In most......
tularemia, acute infectious disease caused by the gram-negative bacterium Francisella tularensis and presenting......
tumour, a mass of abnormal tissue that arises without obvious cause from preexisting body cells, has no purposeful......
turf toe, sprain involving the big toe (hallux) metatarsophalangeal (MTP) joint of the foot. The term turf toe......
turgor, Pressure exerted by fluid in a cell that presses the cell membrane against the cell wall. Turgor is what......
twin, either of two young who are simultaneously born from one mother. Twinning, common in many animals, is of......
tympanic membrane, thin layer of tissue in the human ear that receives sound vibrations from the outer air and......
typhoid fever, acute infectious disease caused by the bacterium Salmonella enterica serovar Typhi. The bacterium......
typhus, series of acute infectious diseases that appear with a sudden onset of headache, chills, fever, and general......
tyrosinemia, inherited inability of the body to metabolize normally the amino acid tyrosine. In the normal metabolic......
ulcer, a lesion or sore on the skin or mucous membrane resulting from the gradual disintegration of surface epithelial......
Ulothrix, genus of filamentous green algae (family Ulotrichaceae) found in marine and fresh waters. Each cell contains......
ultimobranchial gland, in biology, any of the small bodies in the pharynx that develop behind the fifth pair of......
umbilical cord, narrow cord of tissue that connects a developing embryo, or fetus, with the placenta (the extra-embryonic......
ureter, duct that transmits urine from the kidney to the bladder. There normally is one ureter for each kidney.......
urethra, duct that transmits urine from the bladder to the exterior of the body during urination. The urethra is......
urethral gland, in male placental mammals, any of the glands that branch off the internal wall of the urethra,......
