adaptation

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adaptation

 [ad″ap-ta´shun]
1. a dynamic, ongoing, life-sustaining process by which living organisms adjust to environmental changes.
2. adjustment of the pupil to light.
biological adaptation the adaptation of living things to environmental factors for the ultimate purpose of survival, reproduction, and an optimal level of functioning.
color adaptation
1. changes in visual perception of color with prolonged stimulation.
2. adjustment of vision to degree of brightness or color tone of illumination.
dark adaptation adaptation of the eye to vision in the dark or in reduced illumination.
light adaptation adaptation of the eye to vision in the sunlight or in bright illumination (photopia), with reduction in the concentration of the photosensitive pigments of the eye.
physiological adaptation the ongoing process by which internal body functions are regulated and adjusted to maintain homeostasis in the internal environment.
psychological adaptation the ongoing process, anchored in the emotions and intellect, by which humans sustain a balance in their mental and emotional states of being and in their interactions with their social and cultural environments.
social adaptation adjustment and adaptation of humans to other individuals and community groups working together for a common purpose.

ad·ap·ta·tion

(ad'ap-tā'shŭn), Avoid the incorrect form adaption.
1. Preferential survival of members of a species because of a phenotype that enhances their capacity to withstand the environment, including the ecology.
2. An advantageous change in function or constitution of an organ or tissue to meet new conditions.
3. Adjustment of the sensitivity of the retina to light intensity.
4. A property of certain sensory receptors that modifies the response to repeated or continued stimuli at constant intensity.
5. The fitting, condensing, or contouring of a restorative material, foil, or shell to a tooth or cast to ensure close contact.
6. The dynamic process by which the thoughts, feelings, behavior, and biophysiologic mechanisms of the person continually adjust to a constantly changing environment. Synonym(s): adjustment (2)
7. A homeostatic response.
[L. ad-apto, pp. -atus, to adjust]

adaptation

/ad·ap·ta·tion/ (ad″ap-ta´shun)
1. the adjustment of an organism to its environment, or the process by which it enhances such fitness.
2. the normal adjustment of the eye to variations in intensity of light.
3. the decline in the frequency of firing of a neuron, particularly of a receptor, under conditions of constant stimulation.
4. in dentistry, (a) the proper fitting of a denture, (b) the degree of proximity and interlocking of restorative material to a tooth preparation, (c) the exact adjustment of bands to teeth.
5. in microbiology, the adjustment of bacterial physiology to a new environment.

color adaptation 
1. changes in visual perception of color with prolonged stimulation.
2. adjustment of vision to degree of brightness or color tone of illumination.
dark adaptation  adaptation of the eye to vision in the dark or in reduced illumination.
genetic adaptation  the natural selection of the progeny of a mutant better adapted to a new environment.
light adaptation  adaptation of the eye to vision in the sunlight or in bright illumination (photopia), with reduction in the concentration of the photosensitive pigments of the eye.
phenotypic adaptation  a change in the properties of an organism in response to genetic mutation or to a change in the environment.

adaptation

(ăd′ăp-tā′shən)
n.
1.
a. The act or process of adapting.
b. The state of being adapted.
2. Biology
a. The alteration or adjustment in structure or habits, often occurring through natural selection, by which a species or individual becomes better able to function in its environment.
b. A structure or habit that results from this process.
3. Physiology The responsive adjustment of a sense organ, such as the eye, to varying conditions, such as light intensity.
4. Change in behavior of a person or group in response to new or modified surroundings.

ad′ap·ta′tion·al adj.
ad′ap·ta′tion·al·ly adv.

adaptation

[ad′aptā′shən]
Etymology: L, adaptatio, act of adapting
a change or response to stress of any kind, such as inflammation of the nasal mucosa in infectious rhinitis or increased crying in a frightened child. Adaptation may be normal, self-protective, and developmental, as when a child learns to talk; it may be all-encompassing, creating further stress, as in polycythemia, which occurs naturally at high altitudes to provide more oxygen-carrying erythrocytes but may also lead to thrombosis, venous congestion, or edema. The degree and nature of adaptation shown by a patient are evaluated regularly by the members of the health care team. They constitute a measure of the effectiveness of care, the course of the disease, and the ability of the patient to cope with stress. Compare accommodation.

adaptation

Cell biology
The constellation of processes by which an organism adjusts to a new or altered environment in response to stress and increased physiologic demands.
 
Dentistry 
(1) The proper fitting of a denture.
(2) The degree of proximity and interlocking of restorative material to a tooth ‘prep’.
 
Evolutionary biology
A phenotypic feature which improves the reproductive success of a species.

Microbiology
The adjustment of bacteria to a new or altered environment.

Molecular biology
The change in the response of a subcellular system over time; functional or structural changes that allow an organism to respond to changes in the environment; the ability to physiologically adjust to a new environment—typically, cells de-adapt when transferred to different growth conditions.

Ophthalmology
The ability of the eye to adjust to variations in light intensity.
 
Orthodontics
An adjustment of corrective bands resulting in a shifting of the teeth.
 
Physiology
A reduction in the frequency of neuronal firing under conditions of constant stimulation.

adaptation

Opthalmology The ability of the eye to adjust to variations in light intensity Psychology The fitting of behavior to the environment by modifying one's impulses, emotions, or attitudes. See Social adaptation.

ad·ap·ta·tion

(ad'ap-tā'shŭn)
1. Preferential survival of members of a species because of a phenotype that gives them an enhanced capacity to withstand the environment.
2. An advantageous change in function or constitution of an organ or tissue to meet new conditions.
3. Adjustment of the sensitivity of the retina to light intensity.
4. A property of certain sensory receptors that modifies the response to repeated or continued stimuli at constant intensity.
5. dentistry The fitting, condensing, or contouring of a restorative material, foil, or shell to a tooth or cast so as to ensure close contact.
6. The dynamic process wherein the thoughts, feelings, behavior, and biophysiologic mechanisms of a person continually change to adjust to a constantly changing environment.
7. A homeostatic response.
8. occupational therapy the ability to anticipate, correct for, and benefit by learning from the consquences of errors that arise during task performances.
[L. ad-apto, pp. -atus, to adjust]

adaptation

1. Adjustment of sensitivity, usually in the direction of reduction, as a result of repeated stimulation.
2. The adjustment of an organism, including man, in part or in whole, to changes in environment or to external stress. Adaptation is an essential feature of all living things and the likelihood of survival often depends on how effectively it operates.

adaptation

reducing responsiveness of cell surface receptors to repeated constant stimuli

adaptation 

1. Process by which a sensory organ (e.g. the eye) adjusts to its environment (e.g. to luminance, colour or contact lens wear).
2. The reduction in sensitivity to continuous sensory stimulation. The neurophysiological correlate corresponds to a decrease in the frequency of action potentials fired by a neuron, despite a stimulus of constant magnitude. Visual adaptation is prevented from occurring by the continuous involuntary movements of the eyes. See fixation movements; action potential; stabilized retinal image.
chromatic adaptation Apparent changes in hue and saturation after prolonged exposure to a field of a specific colour.
dark adaptation Adjustment of the eye (particularly regeneration of visual pigments and dilatation of the pupil), such that, after observation in the dark, the sensitivity to light is greatly increased, i.e. the threshold response to light is decreased. This is a much slower process than light adaptation. Older people usually take longer to adapt to darkness and only reach a higher threshold than young people. See adaptometer; hemeralopia; visual pigment; duplicity theory.
light adaptation Adjustment of the eye (particularly bleaching of visual pigments and constriction of the pupil), such that, after observation of a bright field, the sensitivity to light is diminished, i.e. the threshold of luminance is increased. See duplicity theory.
prism adaptation See vergence adaptation.
sensory adaptation Mechanism by which the visual system adjusts to avoid confusion and diplopia of the perceptual impression due to an abnormal motor condition (e.g. strabismus).
vergence adaptation A process by which the eyes return to their condition of habitual heterophoria or orthophoria after a heterophoria has been induced by prisms (prism adaptation) in front of one or both eyes (as, for example, when lens centration does not coincide with the interpupillary distance), or by spherical lenses, or due to changes in the orbital contents with increasing age. This adaptation process may be related to the phenomenon of orthophorization. People who have symptomatic binocular vision anomalies do not, or only partially, show vergence adaptation to prisms. Vergence adaptation decreases with increasing age.

ad·ap·ta·tion

(ad'ap-tā'shŭn) Avoid the incorrect form adaption.
1. The fitting, condensing, or contouring of a restorative material, foil, or shell to a tooth or cast to ensure close contact.
2. Alignment of an instrument against a tooth before activation of an exploratory or working stroke.
3. An advantageous change in function or constitution of an organ or tissue to meet new conditions.
4. A homeostatic response.
[L. ad-apto, pp. -atus, to adjust]

adaptation,

n 1. an alteration that an organ or organism undergoes to adjust to its environment.
2. a close approximation of a tissue flap, an appliance, or a restorative material to natural tissue.
3. an accurate adjustment of a band or a shell to a tooth.
4. a condition in reflex activity marked by a decline in the frequency of impulses when sensory stimuli are repeated several times.
adaptation, instrument,
n the process of manually adjusting and positioning the functional end, edge, or surface of a dental instrument for safe and effective use according to its purpose and relative to the shape of the tooth.

adaptation

1. adjustment of the pupil to light, constricting with increased light intensity, dilating with decreased intensity.
2. any anatomical, physiological, developmental or behavioral adjustment to the environment of an organism which enhances its chances of leaving descendants. The ability of animals to adapt to a limited supply of drinking water and to high or low environmental temperatures is an important aspect of animal husbandry. The selection of animals which are capable of a high level of such adaptation has made it possible to improve the productivity of herds and flocks in some countries. See also general adaptation syndrome.
3. the process by which organisms are modified so as to improve their chances of survival in an environment.

dark adaptation
adaptation of the eye to vision in the dark or in reduced illumination.
light adaptation
adaptation of the eye to vision in sunlight or in bright illumination (photopia), with reduction in the concentration of the photosensitive pigments of the eye.
negative adaptation
adaptation rate
the rate at which afferent sensory receptors discharge into their afferent axons. The rates differ between different types of receptors. For example, there are slow adaptors which signal the more persistent changes such as steady pressure. See also receptor adaptation (below).
receptor adaptation
sensory receptors vary in their individual response to stimuli, the response declining after an initial period of rapid response. The rate at which different kinds of receptors change these responses is the adaptation rate (see above).