"Fixation" is a process of stabilization important for anatomical study of biological tissue. To achieve this goal, one must arrest the decomposition caused by tissue enzymes and decay; it is usually desirable also to harden the tissue for convenient handling. The two basic approaches involve physical methods (rapid heating or quick-freezing) and/or chemical methods. Nearly all chemical methods were originally developed for the leather tanning industry, which faces similar problems.
The most widely-used chemical fixative is 4% formaldehyde gas dissolved in water or buffer. This (moderately toxic) agent rapidly penetrates tissue and (more slowly) denatures proteins, arresting enzymatic degradation. It also cross-links proteins, leading to tissue hardening. Glutaraldehyde, a di-aldehyde which cross-links very effectively, is often used for electron microscopy. A wide range of other chemical fixatives are sometimes used, including organic chemicals like tannic acid, picric acid, and absolute alcohol, and (highly toxic) inorganic fixatives like potassium dichromate, mercuric chloride, and osmium tetroxide. Their mechanisms of action are poorly-understood, but generally involve denaturation of protein.
it's slow in fixation of tissue hence the tissue may shrink durinb dehydration proces
red blodd cell hemolysis
Urethropexy is the medical term meaning surgical fixation of the urethra.
dense irregular connective tissue
principle behind zone refining is fractional crystallization; it is a process of separation of solute from its solution.
it works on the principle of refraction
what is the principle behind simple pendulum no because heavy body is suspended with light extensibe string.
yema
Osmosis.
Dna
Behind your lips lie the gums.
The first principle of wound care is the removal of nonviable tissue, including necrotic (dead) tissue, slough, foreign debris, and residual material from dressings.