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Forensic Science Name:______________________________

The Autopsy, Decomposition etc. Pd.____ Date:______________________

Goto:

1. Click on: Decomposition, then Decomposition - body changes, then look at: What is rigor mortis? This site says rigor mortis commences _______________________hours, reaching maximum stiffness after _____ hours, and gradually dissipates until approximately ________ hours after death.

2. What is grave wax? ________________________________________________________________________

___________________________. If a body is accessible to _________________, adipocere is unlikely to form.

3. Go back and click on Image Gallery: Stages of Decomposition: (look at the pig photos)What are the six stages of decomposition?

1. __________________________________

2. __________________________________

3. __________________________________

4. __________________________________

5. __________________________________

6. __________________________________

4. Go Back and click on Corpse Fauna: The dominant groups of organisms involved in decomposition are:

_____________________, _________________, ____________________ and ______________

5. Go back and click on: Decomposition, then Decomposition - Forensic Evidence, scroll way down to “Criminal Case History”: Read the article – Answer this: how did maggot evidence help crack the case?

And – why were the maggots in the woman’s body more developed than the man’s?

6. Go back and click on: What happens after death, and then Autopsies: An autopsy is usually carried out within _____ hours after the death of a person.

7. What are the 3 Level (or types of autopsies?)

1. _________________________________________________

2. _________________________________________________

3. _________________________________________________

8. Go back and click on Morgues and Mortuaries. (Practices in Australia and the U.S. are generally the same)

a. What is a morgue?

b. What is a mortuary?

c. What is embalming?

Goto:

9. To expose the internal organs, a first cut known as the_________________________________ is made.

b. The most common way to remove the organs is known as the _____________________________________________-

which is removing the body organs_____________________________.

c. To remove the brain, an incision is made in the ___________________________________from one ear to the other.

The scalp is cut and separated from the underlying skull and___________________________. The top of the skull is

removed using a______________________________.

d. The organs can be ___________________in the body or the body can be filled with a ____________________before it

is sewn up again.

e. Once the Y incision and the head are sewn up, the autopsy (without brain and tissue analysis) is_________________.

Stitching of the incision is like that on a________________________________.

Goto:

1. Click on Decomposition, body changes and then rigor mortis: this site says rigor mortis commences after around 3 hours, reaching maximum stiffness after 12 hours, and gradually dissipates until approximately 72 hours after death.

2. Click on grave wax: a. what its it? ________________________________________________ b. If a body is readily accessible to insects, adipocere is unlikely to form.

3. Click on Decomposition: What are the six stages of decomposition?

1. Living Pig

2. Initial Decay

3. Putrefaction

4. Black Putrefaction

5. Butyric fermentation

6. Dry Decay

4. Click on Corpse Fauna: The dominant groups of organisms involved in decomposition are bacteria, flies, beetles, mites and moths

5. Click on Forensic Evidence, then on Criminal Case History: Read the article – how did maggot evidence help crack the case?

And – why were the maggots in the woman’s body more developed than the man’s?

6. Click on Death- the Last Taboo and then Autopsies: An autopsy is usually carried out within 48 hours after the death of a person.

7. Click on Home and then on Movies and Interactives under Resources, the click on Interactive Autopsy. Click through the interactive and answer the following questions:

a. To expose the internal organs, a first cut known as the 'Y' incision, is made.

b. The most common way to remove the organs is known as the Rokitansky method - removing the body organs all at once.

c. To remove the brain, an incision is made in the back of the scalp from one ear to the other. The scalp is cut and separated from the underlying skull and pulled forward. The top of the skull is removed using a vibrating saw.

d. The organs can be replaced in the body or the body can be filled with a filler material before it is sewn up again.

e. Once the Y incision and the head are sewn up, the autopsy (without brain and tissue analysis) is complete. Stitching of the incision is like that on a baseball.

8. Click on Home and the Morgues and Mortuaries. (Note: practices in Australia and the U.S. are generally the same)

a. What is a morgue?

b. What is a mortuary?

c. What is embalming?

Decomposition of a corpse is a continual process that can take from weeks to years, depending on the environment. In this website we have divided the process into stages, which are characterised by particular physical conditions of the corpse and the presence of particular animals. To illustrate the process of decomposition, we use the piglet as the model corpse. A 40 kg pig resembles a human body in its fat distribution, cover of hair and ability to attract insects. These factors make pigs the next best things to humans when it comes to understanding the process of decay of the The pigs in this movie were newborn piglets (weighing about 1.5 kg) that were accidentally crushed by their mothers - a key cause of death of piglets. Their bodies were donated to science.

Stage 1: The living pig

State of decay A live pig is not outwardly decomposing, but its intestine contains a diversity of bacteria, protozoans and nematodes. Some of these micro-organisms are ready for a new life, should the pig die and lose its ability to keep them under control.

Stage 2: Initial decay - 0 to 3 days after death

State of decay Although the body shortly after death appears fresh from the outside, the bacteria that before death were feeding on the contents of the intestine begin to digest the intestine itself. They eventually break out of the intestine and start digesting the surrounding internal organs. The body's own digestive enzymes (normally in the intestine) also spread through the body, contributing to its decomposition. On an even smaller scale, enzymes inside individual cells are released when the cell dies. These enzymes break down the cell and its connections with other cells.

Insect activity: From the moment of death flies are attracted to bodies. Without the normal defences of a living animal, blowflies and house flies are able to lay eggs around wounds and natural body openings (mouth, nose, eyes, anus, genitalia). These eggs hatch and move into the body, often within 24 hours. The life cycle of a fly from egg to maggot to fly takes from two to three weeks. It can take considerably longer at low temperatures.

Stage 3: Putrefaction - 4 to 10 days after death

State of decay:Bacteria break down tissues and cells, releasing fluids into body cavities. They often respire in the absence of oxygen (anaerobically) and produce various gases including hydrogen sulphide, methane, cadaverine and putrescine as by-products. People might find these gases foul smelling, but they are very attractive to a variety of insects. The build up of gas resulting from the intense activity of the multiplying bacteria, creates pressure within the body. This pressure inflates the body and forces fluids out of cells and blood vessels and into the body cavity.

Insect activity. The young maggots move throughout the body, spreading bacteria, secreting digestive enzymes and tearing tissues with their mouth hooks. They move as a maggot mass benefiting from communal heat and shared digestive secretions.. The rate of decay increases, and the smells and body fluids that begin to eminate from the body attract more blowflies, flesh flies, beetles and mites. The later-arriving flies and beetles are predators, feeding on maggots as well as the decaying flesh. They are joined by parasitoid wasps that lay their eggs inside maggots and later, inside pupae

Stage 4: Black putrefaction - 10 to 20 days after death

State of decay The bloated body eventually collapses, leaving a flattened body whose flesh has a creamy consistency. The exposed parts of the body are black in colour and there is a very strong smell of decay. A large volume of body fluids drain from the body at this stage and seep into the surrounding soil. Other insects and mites feed on this material.. The insects consume the bulk of the flesh and the body temperature increases with their activity. Bacterial decay is still very important, and bacteria will eventually consume the body if insects are excluded.

Insect activity. By this stage, several generations of maggots are present on the body and some have become fully grown. They migrate from the body and bury themselves in the soil where they become pupae. Predatory maggots are much more abundant at this stage, and the pioneer flies cease to be attracted to the corpse. Predatory beetles lay their eggs in the corpse and their larvae then hatch out and feed on the decaying flesh. Parasitoid wasps are much more common, laying their eggs inside maggots and pupae.

Stage 5: Butyric fermentation - 20 to 50 days after death

State of decay All remaining flesh is removed over this period and the body dries out. It has cheesy smell, caused by butyric acid, and this smell attracts new suite of corpse organisms.

The surface of body that is in contact with the ground becomes covered with mould as body ferments.

Insect activity: The reduction in soft food makes the body less palatable to the mouth-hooks of maggots, and more suitable for the chewing mouthparts of beetles. Beetles feed on the skin and ligaments. Many of these beetles are larvae. They hatch from eggs, laid by adults, which fed on the body in earlier stages of decay. Cheese fly consumes any remaining moist flesh at this stage, even though it is uncommon earlier in decay.

Predators and parasitoids are still present at this stage including numerous wasps and beetle larvae.

Stage 6: Dry decay - 50-365 days after death

State of decay The body is now dry and decays very slowly. Eventually all the hair disappears leaving the bones only.

Insect activity. Animals which can feed on hair include tineid moths, and micro-organisms like bacteria. Mites, in turn, feed on these micro-organisms.

They remain on the body as long as traces of hair remain, which depends on the amount of hair that covers the particular species. Humans and pigs have relatively little hair and this stage is short for these species.

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