Life Cycle, Processes & Properties, DEN-END

None of us are born looking exactly the way that we do today; this is because humans, like other species, undergo a series of changes as they mature and age, in accordance with their biological life cycle. This process can look very different across different species. In many simple organisms and in higher animals, the life cycle is completed within a single generation, while in most plants, the life cycle is multigenerational.
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Life Cycle, Processes & Properties Encyclopedia Articles By Title

dengue
dengue, acute infectious mosquito-borne fever that is temporarily incapacitating but rarely fatal. Besides fever,......
dentin
dentin, in anatomy, the yellowish tissue that makes up the bulk of all teeth. It is harder than bone but softer......
depersonalization
depersonalization, in psychology, a state in which an individual feels that either he himself or the outside world......
depression
depression, in psychology, a mood or emotional state that is marked by feelings of low self-worth or guilt and......
dermatillomania
dermatillomania, psychiatric disorder in which an individual compulsively picks at their skin to the extent that......
dermatitis
dermatitis, an inflammation of the skin usually characterized by redness, swelling, blister formation, and oozing......
dermatochalasis
dermatochalasis, sagging of the eyelid skin and underlying muscle that occurs commonly during the aging process.......
dermatome
dermatome, the outer portion of an embryo from which the skin and subcutaneous tissues are developed and, postnatally,......
dermatomyositis
dermatomyositis, chronic progressive inflammation of the skin and muscles, particularly the muscles of the shoulders......
desquamation
desquamation, peeling or shedding of the superficial portion of the epidermis, or outermost layer of the skin.......
detached retina
detached retina, eye disorder involving separation of the transparent light-sensing portion of the retina from......
diabetes
diabetes, either of two disorders of the endocrine system. For information about the disorder caused by the body’s......
diabetes insipidus
diabetes insipidus, pathological endocrine condition characterized by excessive thirst and excessive production......
diabetes mellitus
diabetes mellitus, disorder of carbohydrate metabolism characterized by impaired ability of the body to produce......
diabetic ketoacidosis
diabetic ketoacidosis, complication of diabetes mellitus, characterized by an abnormal acceleration in the breakdown......
diabetic nephropathy
diabetic nephropathy, deterioration of kidney function occurring as a complication of diabetes mellitus. The condition......
diapause
diapause, spontaneous interruption of the development of certain animals, marked by reduction of metabolic activity.......
diarrhea
diarrhea, abnormally swift passage of waste material through the large intestine, with consequent discharge of......
dieback
dieback, common symptom or name of disease, especially of woody plants, characterized by progressive death of twigs,......
digestion
digestion, sequence by which food is broken down and chemically converted so that it can be absorbed by the cells......
digestive system, invertebrate
invertebrate digestive system, any of the systems used by invertebrates for the process of digestion. Included......
digit malformation
digit malformation, in human physiology, any of the isolated anomalies of the digits (fingers or toes) in an otherwise......
diphtheria
diphtheria, acute infectious disease caused by the bacillus Corynebacterium diphtheriae and characterized by a......
disaster epidemiology
disaster epidemiology, the study of the effects of disasters on human populations, mainly by the use of data collection......
disease
disease, any harmful deviation from the normal structural or functional state of an organism, generally associated......
dislocation
dislocation, in physiology and medicine, displacement of the bones forming a joint, with consequent disruption......
display behaviour
display behaviour, ritualized behaviour by which an animal provides specific information to others, usually members......
dissociative disorder
dissociative disorder, any of several mental disturbances in humans in which normally integrated mental functions,......
dissociative identity disorder
dissociative identity disorder, mental disorder in which two or more independent and distinct personality systems......
distemper
distemper, Viral disease in two forms, canine and feline. Canine distemper is acute and highly contagious, affecting......
diverticulitis
diverticulitis, inflammation of the diverticula, or small pouches, that form in the lining of the large intestine.......
diverticulum
diverticulum, any small pouch or sac that forms in the wall of a major organ of the human body. Diverticula form......
dizygotic twin
dizygotic twin, two siblings who come from separate ova, or eggs, that are released at the same time from an ovary......
dog years explained
How do dogs age in comparison with humans? And are seven dog years really equivalent to one year of human life?......
dominance hierarchy
dominance hierarchy, a form of animal social structure in which a linear or nearly linear ranking exists, with......
doping
doping, use of substances or techniques to illegally improve human performance and, more specifically, to gain......
dormancy
dormancy, state of reduced metabolic activity adopted by many organisms under conditions of environmental stress......
double fertilization
double fertilization, in flowering plant reproduction, the fusion of the egg and sperm and the simultaneous fusion......
double vision
double vision, perceiving of two images of a single object. Normal binocular vision results from the brain’s fusion......
dourine
dourine, venereal disease of horses, caused by the protozoan Trypanosoma equiperdum. The disease, which involves......
Down syndrome
Down syndrome, congenital disorder caused by the presence in the human genome of extra genetic material from chromosome......
downy mildew
downy mildew, disease of plants, especially in cool humid regions, caused by several funguslike organisms of the......
Driesch, Hans Adolf Eduard
Hans Adolf Eduard Driesch was a German experimental embryologist and philosopher who was the last great spokesman......
drowning
drowning, suffocation by immersion in a liquid, usually water. Water closing over the victim’s mouth and nose cuts......
drug abuse
drug abuse, the excessive, maladaptive, or addictive use of drugs for nonmedical purposes despite social, psychological,......
drug allergy
drug allergy, hypersensitivity reaction to therapeutic agents that occasionally occurs on subsequent exposure to......
drug resistance
drug resistance, Property of a disease-causing organism that allows it to withstand drug therapy. In any population......
drupe
drupe, in botany, simple fleshy fruit that usually contains a single seed, such as the cherry, peach, and olive.......
dry rot
dry rot, symptom of fungal disease in plants, characterized by firm spongy to leathery or hard decay of stem (branch),......
Dupuytren’s contracture
Dupuytren’s contracture, flexion deformity of the hands caused by thickening of the fascia, or fibrous connective......
Dutch elm disease
Dutch elm disease, widespread fungoid killer of elms (Ulmus species) and certain other trees, first described in......
dwarfism
dwarfism, condition of growth retardation resulting in abnormally short adult stature and caused by a variety of......
dysarthria
dysarthria, motor speech disorder in which neurological damage impairs the ability of nerves to send messages to......
dysentery
dysentery, infectious disease characterized by inflammation of the intestine, abdominal pain, and diarrhea with......
dyslexia
dyslexia, an inability or pronounced difficulty to learn to read or spell, despite otherwise normal intellectual......
dysmenorrhea
dysmenorrhea, pain or painful cramps felt before or during menstruation. Dysmenorrhea may be primary or secondary.......
dyspareunia
dyspareunia, painful or difficult sexual intercourse in the female. Disorders are generally physical rather than......
dysphagia
dysphagia, difficulty or pain in swallowing, caused by lesions or stricture of the upper digestive tract, obstruction......
dysplasia
dysplasia, malformation of a bodily structure or tissue; the term most commonly denotes a malformation of bone.......
dystonia
dystonia, movement disorder characterized by the involuntary and repetitive contraction of muscle groups, resulting......
ear bone
ear bone, any of the three tiny bones in the middle ear of all mammals. These are the malleus, or hammer, the incus,......
ear squeeze
ear squeeze, effects of a difference in pressure between the internal ear spaces and the external ear canal. These......
earwax impaction
earwax impaction, filling of the external auditory canal with earwax, or cerumen. Normally the wax produced by......
eating disorders
eating disorders, atypical eating patterns, including anorexia nervosa, bulimia, compulsive overeating, and pica......
Ebola
Ebola, contagious disease caused by a virus of the family Filoviridae that is responsible for a severe and often......
ebullism
ebullism, formation of bubbles in the bodily fluids because of an extreme reduction in the surrounding pressure.......
echinococcosis
echinococcosis, formation of cysts, or hydatids, at the site of infestation by the larval form of Echinococcus......
ecological fallacy
ecological fallacy, in epidemiology, failure in reasoning that arises when an inference is made about an individual......
ectoderm
ectoderm, the outermost of the three germ layers, or masses of cells, which appears early in the development of......
ectopic pregnancy
ectopic pregnancy, condition in which the fertilized ovum (egg) has become imbedded outside the uterine cavity.......
ectotherm
ectotherm, any so-called cold-blooded animal—that is, any animal whose regulation of body temperature depends on......
ectropion
ectropion, outward turning of the border (or margin) of the eyelid (usually the lower eyelids). The condition most......
edema
edema, in medicine, an abnormal accumulation of watery fluid in the intercellular spaces of connective tissue.......
egg
egg, in biology, the female sex cell, or gamete. In botany, the egg is sometimes called a macrogamete. In zoology,......
egg tooth
egg tooth, tooth or toothlike structure used by the young of many egg-laying species to break the shell of the......
Ehlers-Danlos syndrome
Ehlers-Danlos syndrome (EDS), rare heritable disorder characterized primarily by great elasticity of the skin,......
elbow injuries
elbow injuries, the common sprains, dislocations, and fractures caused by forced movement of the joint beyond its......
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......
elephantiasis
elephantiasis, condition associated with the infectious diseases known collectively as filariasis. Elephantiasis......
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......
emotional development
emotional development, emergence of the experience, expression, understanding, and regulation of emotions from......
emphysema
emphysema, condition characterized by widespread destruction of the gas-exchanging tissues of the lungs, resulting......
empyema
empyema, accumulation of pus in a cavity of the body, usually in the pleura, which are the serous membranes covering......
enamel
enamel, in anatomy, the hardest tissue of the body, covering part or all of the crown of the tooth in mammals.......
encephalitis
encephalitis, from Greek enkephalos (“brain”) and itis (“inflammation”), inflammation of the brain. Inflammation......
encephalitis lethargica
encephalitis lethargica, form of encephalitis that emerged in the early 20th century. An encephalitis lethargica......
enchondroma
enchondroma, solitary benign cartilaginous tumour that occurs mostly in the shafts of bones of the hands and feet,......
endocarditis
endocarditis, inflammation of the heart lining, or endocardium. Endocarditis is caused by any of a number of microorganisms,......
endocrine disruptor
endocrine disruptor, any chemical that mimics or interferes with the normal actions of hormones in the body. Endocrine......
endoderm
endoderm, the innermost of the three germ layers, or masses of cells (lying within ectoderm and mesoderm), which......
endometriosis
endometriosis, disorder of the female reproductive system characterized by the growth of endometrial tissue (uterine......
endometritis
endometritis, inflammation of the endometrium, the mucous lining of the uterus. Endometritis is most commonly caused......
endosperm
endosperm, tissue that surrounds and nourishes the embryo in the seeds of angiosperms (flowering plants). In some......

Life Cycle, Processes & Properties Encyclopedia Articles By Title