Rigor Mortis Research Paper

The anatomy and physiology of the human body explains that muscles are attached to the skeleton. They work like hinges or levers to pull or move particular joints when a muscle contracts, pulling the joint in the direction it is designed to move. Parts of muscles move antagonistically, that is, when one contracts, its opposite member relaxes to allow movement. Muscles can become slack, making movement slower and more difficult.

ATP is required to break the attachment of actin to the myosin head. At death, calcium ions leak out of the SR

Muscle atrophy is the loss of skeletal muscle mass and function that occurs when there is a long period of inactivity of the muscles or defects in motor neuron's (Reilly, Beau 2015). Defects in the motor neurons that stimulate the muscle cause the muscle mass to decrease as proteins that initiate contractions of muscle dissipate. Stimulus is not transferred to the weakened muscle fibers effectively, reducing the contractile force possible for generation from the stimulus. Muscle mass increases upon recovery, as restimulation of the muscle enlarges fiber size, thus a greater contractile force can be generated from the stimulus.

This activity is the critical driving force of muscle contraction. The stream of action potentials along the muscle fiber surface is terminated as Acetylcholine at the neuromuscular junction is broken down by acetyl cholinesterase. The release of Calcium ions is ceased. The action of the myosin molecule heads is obstructed because of the change in the configuration of troponin and tropomyosin due to the absence of calcium ions. This will eventually cause the contraction to be ceased. Together with these physical processes, an external stretching force such as gravity pulls the muscle back to its normal length.

Soon after death, anywhere from two to six hours after passing, an event called rigor mortis begins. Rigor mortis is the third stage of death. Rigor mortis is the stiffening or tensing of muscles after death. It is what causes a deceased person's eyelids to open. Rigor mortis is caused by the contraction of muscles in the body immediately after death. It starts with long, narrow bundles of cells that form muscle tissue. These cells build up electric potential by actively pumping out calcium ions. A neuron will release a signal, and when the muscle cells receive it, they open up the calcium channels in their cell membranes. The calcium ions will then rush out through the cell membranes due to the difference in voltage inside and outside of the cell. “Calcium ions will interact with actin and myosin filaments to cause muscle contraction.”(Source 6) Muscles will remain contracted, or in a contracted state, until ATP binds to myosin. When ATP binds to myosin, it releases the myosin and actin from each other, causing the muscles to release. However, when a person is dead they can no longer produce ATP, therefore, the muscles stay clenched. This causes the body to have a sickly stiff appearance. After the muscles have stiffened, the body moves on to the next stage of death.

twitch muscles. Fast twitch muscles have a fast form of myosin ATP and are very

A post mortem change is the term used to describe any changes which are observed in a subject after death has occurred. Post mortem changes which may be observed in a cadaver include algor mortis, rigor mortis, liver mortis, post mortem blood alterations and subsequent clotting, purification and autolysis (Unknown, 2013). However, histological tissue samples may undergo a series of alterations which causes alterations in tissue structure to occur. Alterations in tissue structure may encourage disparity between expected staining and the subsequent reactions to

Heavy weight on body parts may partially or completely cut off blood flow. Decrease in oxygen supply leads to anaerobic metabolism, skeletal muscle tissue begins to break down. As muscle cells die, they absorb sodium, water and calcium; releases potassium, myoglobin,

c. After about 36 hours, rigor mortis usually disappears in the same sequence as it appeared.

“Skeletal muscle is a protein reservoir that can be mobilised in times of need” – A Goldberg. Muscle ‘atrophy is defined as a decrease in the size of a tissue or organ due to cellular shrinkage; the decrease in cell size is caused by the loss of organelles, cytoplasm and proteins’ (Sandri, M. and Bonaldo, P. 2013). Muscle atrophy is the wasting away of muscles mainly due to inactivity or in this patient’s case, being bed ridden for 2 months. The principle of use it or lose it comes into play as the muscle is not being used and the body decides to stop providing a nutrient supply for the muscle and thus the atrophy of muscle occurs. Muscle mass increases following atrophy through a process of hypertrophy; the enlargement of muscle fibres. ‘Muscle

Both of these muscles expand and contract as they have complex structures so it is essential how they do this. The cardiac muscle needs the contractions to occur in order to pump blood out of the atria and into the ventricles and round the circulatory system so the structure of this muscle shows the systole of the heart. The contractions of the skeletal muscle also depend on its structure. The binding and releasing of two strands of sarcomere is how the repeated pattern of contractions occurs. ATP is used to prepare myosin for binding to allow the contractions to happen. The skeletal and cardiac muscle also both has elasticity. The elasticity is used to restore the muscles back to their original lengths which enable them to resume back to their original length once they have contracted and been stretched.

Smooth muscle and cardiac muscle are both involuntary. Smooth muscle also has less myosin than and doesn’t generate as much tension as skeletal muscle does which is due to different functions in the body. 3. When a person dies, their body goes through a period of rigor mortis. Which occurs when ATP binds to myosin which releases myosin and actin filaments forcing the body to remain contracted.

known as corpse wax or the fat of graveyards, is a product of decomposition that turns body fat into a soap-like

riginality does help an essay t o stand out. With this in mind, it is worth rejecting common topics such as euthanasia, legalisation of drugs, drugs in sport , death penalty . . . Apart from their lack of freshness , these topics are very wide and are likely to be covered in a superficial way in 1, 0 00 words. 2.

The last stage is called skeletonization. It lasts months to years. Fat in the body begins to decompose. If a corpse is exposed to soil or cold water, adipocere -