Biology, EHL-FIB

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.
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Biology Encyclopedia Articles By Title

Ehlers-Danlos syndrome
Ehlers-Danlos syndrome (EDS), rare heritable disorder characterized primarily by great elasticity of the skin,......
ejaculatory duct
ejaculatory duct, either of two hollow tubes, each formed by union of the ampulla of a ductus deferens (q.v.) and......
elastic fibre
elastic fibre, any of the yellowish branching fibres composed primarily of the protein elastin, frequently arranged......
elbow
elbow, in human anatomy, hinge joint formed by the meeting of the humerus (bone of the upper arm) and the radius......
electrical shock
electrical shock, the perceptible and physical effect of an electrical current that enters the body. The shock......
electroreception
electroreception, the ability to detect weak naturally occurring electrostatic fields in the environment. Electroreception......
embolism
embolism, obstruction of the flow of blood by an embolus, a particle or aggregate of substance that is abnormally......
embryo
embryo, the early developmental stage of an animal while it is in the egg or within the uterus of the mother. In......
embryology
embryology, the study of the formation and development of an embryo and fetus. Before widespread use of the microscope......
emergence
emergence, in evolutionary theory, the rise of a system that cannot be predicted or explained from antecedent conditions.......
emotional development
emotional development, emergence of the experience, expression, understanding, and regulation of emotions from......
empyema
empyema, accumulation of pus in a cavity of the body, usually in the pleura, which are the serous membranes covering......
encephalitis
encephalitis, from Greek enkephalos (“brain”) and itis (“inflammation”), inflammation of the brain. Inflammation......
ENCODE
ENCODE, collaborative data-collection project begun in 2003 that aimed to inventory all the functional elements......
end-Triassic extinction
end-Triassic extinction, global extinction event occurring at the end of the Triassic Period (about 252 million......
endangered species
endangered species, any species that is at risk of extinction because of a sudden rapid decrease in its population......
endemic species
endemic species, in ecology, any species or other taxon whose geographic range or distribution is confined to a......
endocrine disruptor
endocrine disruptor, any chemical that mimics or interferes with the normal actions of hormones in the body. Endocrine......
endocrinology
endocrinology, medical discipline dealing with the role of hormones and other biochemical mediators in regulating......
endometriosis
endometriosis, disorder of the female reproductive system characterized by the growth of endometrial tissue (uterine......
endoplasmic reticulum
endoplasmic reticulum (ER), in biology, a continuous membrane system that forms a series of flattened sacs within......
endosperm
endosperm, tissue that surrounds and nourishes the embryo in the seeds of angiosperms (flowering plants). In some......
Enterobacter
Enterobacter, (genus Enterobacter), any of a group of rod-shaped bacteria of the family Enterobacteriaceae. Enterobacter......
entomology
entomology, branch of zoology dealing with the scientific study of insects. The Greek word entomon, meaning “notched,”......
entropion
entropion, inward turning of the border (or margin) of the eyelid (usually the lower eyelids), occurring most often......
ependymal cell
ependymal cell, type of neuronal support cell (neuroglia) that forms the epithelial lining of the ventricles (cavities)......
ephemeral
ephemeral, in botany, any short-lived plant, usually one that has one or more generations per year, growing only......
epicanthic fold
epicanthic fold, fold of skin across the inner corner of the eye (canthus). The epicanthic fold produces the eye......
epidemic
epidemic, an occurrence of disease that is temporarily of high prevalence. An epidemic occurring over a wide geographical......
epidemiology
epidemiology, branch of medical science that studies the distribution of disease in human populations and the factors......
epidermis
epidermis, in zoology, protective outermost portion of the skin. There are two layers of epidermis, the living......
epididymitis
epididymitis, inflammation of the epididymis, the cordlike structure that runs along the posterior of the testis......
epigenetics
epigenetics, the study of the chemical modification of specific genes or gene-associated proteins of an organism.......
epigenomics
epigenomics, the study of chemical changes that regulate the expression, or use, of the entire collection of DNA......
epilepsy
epilepsy, chronic neurological disorder characterized by sudden and recurrent seizures which are caused by an absence......
epithelium
epithelium, in anatomy, layer of cells closely bound to one another to form continuous sheets covering surfaces......
Epperson v. State of Arkansas
Epperson v. State of Arkansas, case in which the U.S. Supreme Court on November 12, 1968, ruled (9–0) that an Arkansas......
Epstein-Barr virus
Epstein-Barr virus (EBV), virus of the Herpesviridae family that is the major cause of acute infectious mononucleosis,......
equine encephalitis
equine encephalitis, severe viral disease of horses and mules, transmitted by mosquitoes. It sometimes affects......
equine infectious anemia
equine infectious anemia (EIA), disease of horses that is caused by a non-oncogenic (non-cancer-causing) retrovirus.......
equine respiratory disease
equine respiratory disease, a complex of infections of viral origin, including equine viral rhinopneumonitis (viral......
erector spinae
erector spinae, a deep muscle of the back; it arises from a tendon attached to the crest along the centre of the......
ergot
ergot, fungal disease of cereal grasses, especially rye, caused by species of the ascomycete fungus Claviceps.......
erysipelas
erysipelas, contagious infection of the skin and underlying tissue, caused by group A B-hemolytic streptococcus......
erysipelothrix infection
erysipelothrix infection, any of several infectious diseases caused by the widespread bacterium Erysipelothrix......
erythema
erythema, any abnormal redness of the skin. Erythema is caused by dilation and irritation of the superficial capillaries;......
erythrasma
erythrasma, a superficial skin infection marked by reddish brown scaly patches and attributed to the bacterium......
erythroblast
erythroblast, nucleated cell occurring in red marrow as a stage or stages in the development of the red blood cell,......
erythroblastosis fetalis
erythroblastosis fetalis, type of anemia in which the red blood cells (erythrocytes) of a fetus are destroyed in......
esophageal cancer
esophageal cancer, disease characterized by the abnormal growth of cells in the esophagus, the muscular tube connecting......
esophagus
esophagus, relatively straight muscular tube through which food passes from the pharynx to the stomach. The esophagus......
essential tremor
essential tremor, disorder of the nervous system characterized by involuntary oscillating movements that typically......
estrogen
estrogen, any of a group of hormones that primarily influence the female reproductive tract in its development,......
ethnobotany
ethnobotany, systematic study of the botanical knowledge of a social group and its use of locally available plants......
ethology
ethology, the study of animal behaviour. Although many naturalists have studied aspects of animal behaviour through......
eubacterium
eubacterium, term formerly used to describe and differentiate any of a group of prokaryotic true bacteria from......
eugenics
eugenics, the selection of desired heritable characteristics in order to improve future generations, typically......
Euglena
Euglena, genus of more than 1,000 species of single-celled flagellated (i.e., having a whiplike appendage) microorganisms......
eukaryote
eukaryote, any cell or organism that possesses a clearly defined nucleus. The eukaryotic cell has a nuclear membrane......
Eurotiomycetes
Eurotiomycetes, class of fungi in the phylum Ascomycota (sac fungi) within the kingdom Fungi. The members of Eurotiomycetes......
eusocial species
eusocial species, any colonial animal species that lives in multigenerational family groups in which the vast majority......
eustachian tube
eustachian tube, hollow structure that extends from the middle ear to the pharynx (throat). The eustachian tube......
evergreen
evergreen, any plant that retains its leaves through the year and into the following growing season. Many tropical......
exercise-induced pulmonary hemorrhage
exercise-induced pulmonary hemorrhage, disease condition in horses in which blood appears in the airways during......
exophthalmos
exophthalmos, abnormal protrusion of one or both eyeballs. The most common cause for unilateral or bilateral exophthalmos......
exoskeleton
exoskeleton, rigid or articulated envelope that supports and protects the soft tissues of certain animals. The......
extensor muscle
extensor muscle, any of the muscles that increase the angle between members of a limb, as by straightening the......
external auditory canal
external auditory canal, passageway that leads from the outside of the head to the tympanic membrane, or eardrum......
extinction
extinction, in biology, the dying out or extermination of a species. Extinction occurs when species are diminished......
eye colour
eye colour, heritable phenotypic (observable) trait determined by pigmentation and light scattering in the iris......
eyeball
eyeball, spheroidal structure containing sense receptors for vision, found in all vertebrates and constructed much......
eyelid
eyelid, movable tissue, consisting primarily of skin and muscle, that shields and protects the eyeball from mechanical......
Fabry’s disease
Fabry’s disease, sex-linked hereditary disease in which a deficiency in the enzyme alpha-galactosidase A results......
facultative anaerobe
facultative anaerobe, any organism that is able to grow either with or without free oxygen. Facultative anaerobes......
false pregnancy
false pregnancy, disorder that may mimic many of the effects of pregnancy, including enlargement of the uterus,......
familial hypercholesterolemia
familial hypercholesterolemia, an inherited metabolic disease that is caused by deficiency of the LDL (low-density......
farmer’s lung
farmer’s lung, a pulmonary disorder that results from the development of hypersensitivity to inhaled dust from......
fascia
fascia, network of connective tissue that envelops and supports the various structures and organs of the body,......
fascioliasis
fascioliasis, infection of humans and grass-grazing animals caused by the liver fluke Fasciola hepatica, a small......
fasciolopsiasis
fasciolopsiasis, infection of humans and swine by the trematode Fasciolopsis buski, a parasitic worm. Human and......
feces
feces, solid bodily waste discharged from the large intestine through the anus during defecation. Feces are normally......
feedback
feedback, in biology, a response within a system (molecule, cell, organism, or population) that influences the......
feline distemper
feline distemper, viral disease of cats, kittens two to six months old being most susceptible. Highly contagious,......
feline leukemia
feline leukemia, viral disease of cats, one of the most serious diseases affecting domestic cats and a few other......
feline respiratory disease
feline respiratory disease, a complex of viral contagions of cats (including rhinotracheitis, pneumonitis, and......
fermentation
fermentation, chemical process by which molecules such as glucose are broken down anaerobically. More broadly,......
fertility
fertility, ability of an individual or couple to reproduce through normal sexual activity. About 90 percent of......
fertility rate
fertility rate, average number of children born to women during their reproductive years. For the population in......
fertilization
fertilization, union of a sperm nucleus, of paternal origin, with an egg nucleus, of maternal origin, to form the......
fetal alcohol syndrome
fetal alcohol syndrome (FAS), various congenital abnormalities in the newborn infant that are caused by the mother’s......
fetus
fetus, the unborn young of any vertebrate animal, particularly of a mammal, after it has attained the basic form......
fibroblast
fibroblast, the principal active cell of connective tissue. Fibroblasts are large, flat, elongated (spindle-shaped)......
fibroma
fibroma, any benign tumour of fibrous tissue. Specific fibromas include nonossifying fibroma, found in the large......
fibromyalgia
fibromyalgia, chronic syndrome that is characterized by musculoskeletal pain, often at multiple anatomical sites,......

Biology Encyclopedia Articles By Title