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Information about Rigor Mortis

Signs of death
Pallor mortis
Algor mortis
Rigor mortis
Livor mortis Decomposition


This article is about the sign of death. For other uses, see Rigor mortis (disambiguation).


Rigor mortis is one of the recognizable signs of death (Latin mors, mortis) that is caused by a chemical change in the muscles after death, causing the limbs of the corpse to become stiff (Latin rigor) and difficult to move or manipulate.

Description

Assuming mild temperatures, rigor usually sets in about 3-4 hours after clinical death, with full rigor being in effect at about 12 hours, and eventually subsiding to relaxation at about 72 hours. Times for the onset of rigor mortis can vary from a few minutes to several hours depending on the ambient temperature. Factors influencing rigor mortis include the age and condition of the body, as well as the mode of death and the surroundings. For example, rigor mortis will tend to set in faster in those who were active immediately prior to death.

Biochemistry

The biochemical cause of rigor mortis is hydrolysis of ATP, the chemical energy source required for movement, in the muscle tissue. Myosin molecules devoid of ATP become permanently adherent to actin filaments to form actomyosin complex, causing muscles to become rigid. After the pH of the muscle has become 5.5, release of autolytic enzymes stored in lysosomes will take place. The major proteolytic enzymes are Cathepsins and Calpains. These enzymes act at the myofibrillar proteins and hydrolyse them. As a result, the actomyosin complex is broken down and muscles become "soft" again. This is known as resolution of rigor.

Forensics

Rigor Mortis is important in forensics as it allows the pathologist to estimate time of death and to determine position of the body at time of death. Conditions similar to rigor mortis include freezing of the body, heat coagulation, putrefaction and cadaveric spasm.

Rigor mortis and the meat industry

Rigor mortis is very important in meat technology. The onset of rigor mortis and its resolution partially determines the tenderness of meat. If the post-slaughter meat is immediately chilled to 15 °C, a phenomenon known as cold shortening occurs, where the muscle shrinks to a third of its original size. This will lead to the loss of water from the meat along with many of the vitamins, minerals, and water soluble proteins. The loss of water makes the meat hard and interferes with the manufacturing of several meat products like cutlet and sausage.

Cold shortening is caused by the release of stored calcium ions from the sarcoplasmic reticulum of muscle fibers in response to the cold stimulus. The calcium ions trigger powerful muscle contraction aided by ATP molecules. To prevent cold shortening, a process known as electrical stimulation is carried out, especially in beef carcass, immediately after slaughter and flaying. In this process, the carcass is stimulated with alternating current, causing it to contract and relax, which depletes the ATP reserve from the carcass and prevents cold shortening.

See also

Death is the permanent end of the life of a biological organism. Death may refer to the end of life as either an event or condition.[1] Many factors can cause or contribute to an organism's death, including predation, disease, habitat destruction, senescence,
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Pallor mortis (Latin: paleness of death) is a postmortem paleness which happens almost instantaneously (in the 15–120 minutes after the death) because of a lack of capillary circulation throughout the body.
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Algor mortis (Latin: algor—coolness; mortis—of death) is the reduction in body temperature following death. This is generally a steady decline until matching ambient temperature, although external factors can have a significant influence.
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Livor mortis or postmortem lividity (Latin: livor—bluish color, mortis—of death), one of the signs of death, is a settling of the blood in the lower (dependent) portion of the body, causing a purplish red discoloration of the skin: when the
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Decomposition (or spoilage) refers to the reduction of the body of a formerly living organism into simpler forms of matter.

Plant decomposition

See also:  and

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Rigor mortis is one of the recognizable signs of death.

It may also refer to:
  • Rigor Mortis, the thrash metal band
  • Rigor Mortis, the BBC Radio 4 comedy series

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Latin}}} 
Official status
Official language of: Vatican City
Used for official purposes, but not spoken in everyday speech
Regulated by: Opus Fundatum Latinitas
Roman Catholic Church
Language codes
ISO 639-1: la
ISO 639-2: lat
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MUSCLE (multiple sequence comparison by log-expectation) is public domain, multiple sequence alignment software for protein and nucleotide sequences.
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Death is the permanent end of the life of a biological organism. Death may refer to the end of life as either an event or condition.[1] Many factors can cause or contribute to an organism's death, including predation, disease, habitat destruction, senescence,
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body is the integral physical material of an individual. "Body" often is used in connection with appearance, health issues and death. The study of the workings of the body is physiology.
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Latin}}} 
Official status
Official language of: Vatican City
Used for official purposes, but not spoken in everyday speech
Regulated by: Opus Fundatum Latinitas
Roman Catholic Church
Language codes
ISO 639-1: la
ISO 639-2: lat
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Clinical death is the popular term for cessation of blood circulation and breathing.[1] It occurs when the heart stops beating in a regular rhythm, a condition called cardiac arrest. The term is also sometimes used in resuscitation research.
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:Not to be confused with electrolysis


Hydrolysis is a chemical reaction or process in which a chemical compound is broken down by reaction with water.[1][2] This is the type of reaction that is used to break down polymers.
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Adenosine 5'-triphosphate (ATP) is a multifunctional nucleotide that is most important as a "molecular currency" of intracellular energy transfer. In this role, ATP transports chemical energy within cells for metabolism.
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Myosins are a large family of motor proteins found in eukaryotic tissues. They are responsible for actin-based motility.

Structure and Function

Domains

Most myosin molecules are composed of both a head and a tail domain.
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Actin is a globular structural, 42-47 kDa protein found in many eukaryotic cells, with concentrations of over 100 μM. It is also one of the most highly conserved proteins, differing by no more than 5% in species as diverse as algae and humans.
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Myofibrils (obsolete term: sarcostyles) are cylindrical organelles, found within muscle cells. They are bundles of actomyosin filaments that run from one end of the cell to the other and are attached to the cell surface membrane at each end.
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    pH is a measure of the acidity or alkalinity of a solution. Aqueous solutions at 25 ℃ with a pH less than seven are considered acidic, while those with a pH greater than seven are considered basic (alkaline). The pH of 7.
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    Lysosomes are organelles that contain digestive enzymes (acid hydrolases). They digest excess or worn out organelles, food particles, and engulfed viruses or bacteria. The membrane surrounding a lysosome prevents the digestive enzymes inside from destroying the cell.
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    Proteolysis is the directed degradation (digestion) of proteins by cellular enzymes called proteases or by intramolecular digestion.

    Purposes

    Proteolysis is used by the cell for several purposes.
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    Enzymes are proteins that catalyze (i.e. accelerate) chemical reactions.[1] In enzymatic reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, the products.
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    A cathepsin is a protease, a type of protein that breaks apart other proteins, found in many types of cells including those in all animals. There are approximately a dozen members of this family, which are distinguished by their structure and which proteins they cleave.
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    Calpains (EC 3.4.22.52 , EC 3.4.22.53 ) are a family of calcium-dependent, non-lysosomal cysteine proteases (proteolytic enzymes) expressed ubiquitously in mammals and many lower organisms. Calpains constitute the C2 family of protease clan CA in the MEROPS database.
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    Forensic science (often shortened to forensics) is the application of a broad spectrum of sciences to answer questions of interest to the legal system. This may be in relation to a crime or to a civil action.
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    Putrefaction is the decomposition of animal proteins, especially by anaerobic microorganisms, described as putrefying bacteria. Decomposition is a more general process. Putrefaction usually results in amines such as putrescine and cadaverine, which have a putrid odor.
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    Cadaveric spasm, also known as instantaneous rigor, cataleptic rigidity, or instantaneous rigidity, is a rare form of muscular stiffening that occurs at the moment of death, persists into the period of rigor mortis[1]
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    Meat, in its broadest definition, is animal tissue used as food. Most often it refers to skeletal muscle and associated fat, but it may also refer to non-muscle organs, including lungs, livers, skin, brains, bone marrow and kidneys.
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    The meat packing industry is an industry that handles the slaughtering, processing and distribution of animals such as cattle, pigs, sheep and other livestock.

    The industry is primarily focused on producing meat for human consumption, but it also yields a variety of
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    Cutlet (derived from French côtelette, côte ("rib")) refers to:
    1. a thin slice of meat from the leg or ribs of veal, pork, mutton, or lamb (also known in various langagues as a côtelette, Kotelett, or cotoletta.

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    sausage is a type of food usually consisting of ground meat, animal fat, salt, and spices, and sometimes other ingredients such as herbs, sometimes packed in a casing. Sausage making is a very old food preservation technique.
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