tonicity

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Related to tonicities: hypertonic, isotonicity, Hypotonic solution

tonicity

 [to-nis´ĭ-te]
the state of tissue tone or tension; in body fluid physiology, the effective osmotic pressure equivalent.

to·nic·i·ty

(tō-nis'i-tē),
1. A state of normal tension of the tissues by virtue of which the parts are kept in shape, alert, and ready to function in response to a suitable stimulus. In the case of muscle, it refers to a state of continuous activity or tension beyond that related to the physical properties; that is, it is active resistance to stretch; in skeletal muscle it is dependent upon the efferent innervation.
See also: isotonicity. Synonym(s): tonus
2. The osmotic pressure or tension of a solution, usually relative to that of blood.
See also: isotonicity.
[G. tonos, tone]

tonicity

/to·nic·i·ty/ (to-nis´ĭ-te) the state of tissue tone or tension; in body fluid physiology, the effective osmotic pressure equivalent.

tonicity

(tō-nĭs′ĭ-tē)
n. pl. tonici·ties
1. Normal firmness or functional readiness in body tissues or organs.
2. The sustained partial contraction of resting or relaxed muscles.

tonicity

[tōnis′itē]
Etymology: Gk, tonikos, stretching
the quality of possessing tone, or tonus.

to·nic·i·ty

(tō-nis'i-tē)
1. A state of normal tension of the tissues by virtue of which the parts are kept in shape, alert, and ready to function in response to a suitable stimulus. In the case of muscle, it refers to a state of continuous activity or tension beyond that related to the physical properties, i.e., its active resistance to stretch; in skeletal muscle, it is dependent on the efferent innervation.
Synonym(s): tonus.
2. The osmotic pressure or tension of a solution, usually relative to that of blood.
See also: isotonicity
[G. tonos, tone]

solution, hypertonic 

A solution with an osmotic pressure greater than that of an isotonic solution. Hypertonic ophthalmic solutions cause some stinging when instilled. Examples: sodium chloride 5%: when applied to an oedematous cornea this solution reduces oedema by drawing water from it; sulfacetamide sodium 30%; glycerol (or glycerin), at a dose of 1-1.5 g/kg body weight given as a solution with water or other liquid, which draws water from the eye into the blood and thereby reduces the intraocular pressure. Syn. hyperosmotic agent. See hyperosmotic agent; osmotic pressure; physiological saline.
hypotonic s. A solution with an osmotic pressure lower than that of an isotonic solution. Hypotonic ophthalmic solutions generally cause less irritation than hypertonic ones. See osmotic pressure.
isotonic s. A solution with an osmotic pressure equal to that on the other side of a semipermeable membrane. Example: sodium chloride 0.9% is considered to be approximately isotonic with the tears. See osmotic pressure; physio-logical saline.

tonicity

the state of tissue tone or tension; in body fluid physiology, the effective osmotic pressure equivalent.