Alzheimer's Disease is a progressive and irreversible brain disease that destroys mental
 and physical functioning  in human beings, and invariably leads to death.  It is the fourth
 leading cause of adult death in the United States.  Alzheimer's creates emotional and
 financial catastrophe for many American families every year, but fortunately,  a large
 amount of progress is being made to combat Alzheimer's disease every year. To fully be able
 to comprehend and combat Alzheimer's disease,  one must know what it does to the brain, 
 the part of the human body it most greatly affects.  Many Alzheimer's disease sufferers had
 their brains examined.  A large number of differences were present when comparing the
 normal brain to the Alzheimer's brain.  There was a loss of nerve cells from the Cerebral
 Cortex in the Alzheimer's victim.  Approximately ten percent of the neurons in this region
 were lost.  But a ten percent loss is relatively minor,  and cannot account for the severe
 impairment suffered by Alzheimer's victims. Neurofibrillary Tangles are also found in the
 brains of Alzheimer's victims.  They are found within the cell bodies of nerve cells in the
 cerebral cortex,  and take on the structure of a paired helix.  Other diseases that have
 "paired helixes" include Parkinson's disease,  Down's Syndrome,  and Dementia Pugilistica. 
 Scientists are not sure how the paired helixes are related in these very different
 diseases. Neuritic Plaques are patches of clumped material lying outside the bodies of
 nerve cells in the brain.  They are mainly found in the cerebral cortex,  but have also
 been seen in other areas of the brain.  At the core of each of these plaques is a substance
 called amyloid,  an abnormal protein not usually found in the brain.  This amyloid core is
 surrounded by cast off fragments of dead or dying nerve cells.  The cell fragments include
 dying mitochondria,  presynaptic terminals,  and paired helical filaments identical to
 those that are neurofibrillary tangles.  Many neuropathologists think that these plaques
 are basically clusters of degenerating nerve cells.  But they are still not sure of how and
 why these fragments clustered together. Congophilic Angiopathy is the technical name that
 neuropathologists have given to an abnormality found in the walls of blood vessels in the
 brains of victims of Alzheimer's disease.  These abnormal patches are similar to the
 neuritic plaques that develop in Alzheimer's disease,  in that amyloid has been found
 within the blood-vessel walls wherever the patches occur.  Another name for these patches
 is cerebrovascular amyloid,  meaning amyloid found in the blood vessels of the brains.
 Acetylcholine is a substance that carries signals from one nerve cell to another.  It is
 known to be important to learning and memory.  In the mid 1970s,  scientists found that the
 brains of those afflicted with Alzheimer's disease contained sixty to ninety percent less
 of the enzyme choline acetyltransferase(CAT),  which is responsible for producing
 acetylcholine,  than did the brains of healthy persons.  This was a great milestone,  as it
 was the first functional change related to learning and memory,  and not to different
 structures. Somatostatin is another means by which cells in the brain communicate with each
 other.  The quantities of this chemical messenger,  like those of CAT,  are also greatly
 decreased in the cerebral cortex and the hippocampus of persons with Alzheimer's disease, 
 almost to the same degree as CAT is lost. Although scientists have been able to identify
 many of these,  and other changes,  they are not yet sure as to how,  or why they take
 place in Alzheimer's disease.  One could say,  that they have most of the pieces of the
 puzzle;  all that is left to do is find the missing piece and decipher the meaning. If
 treatment is required for someone with Alzheimer's disease,  then the Alzheimer's Disease
 and Related Disorders Association(ADRDA),  a privately funded,  national,  non-profit
 organization dedicated to easing the burden of Alzheimer victims and their families and
 finding a cure can be contacted.  There are more than one hundred and sixty chapters
 throughout the country,  and over one thousand support groups that can be contacted for
 help.  ADRDA fights Alzheimer's on five fronts 1- funding research 2- educating and thus
 increase public awareness 3- establishing chapters with support groups 4- encouraging
 federal and local legislation to help victims and their families 5- providing a service to
 help victims and their families find the proper care they need.
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nsects are neumerout invertebrate animals that belong in the Phylum 
Arthropoda and Class Insecta.  The class Insecta is divided into 2 subclasses: 
Apterygota, or wingless insects, and Pterygota, or winged insects. Subclass 
Pterygota is futher divided on basis of metamorphosis. Insects that have 
undergone incomplete metamorphosis are the Exopterygota. Insects that undergo 
complete metamorphosis are the Endopterygota.

 Insects have an outer bilateral exoskeleton to which the muscles are attached 
to and provides protection for internal organs. The body is divided into 3 
main parts which are the head, which include mouthparts, eyes, and antennae; 
thorax, which operate the jointed legs and /or wings; and abdomen, which has 
organs for digested food, reproducing, and getting rid of waste products.

 The major systems in insects are the circulatory, respiratory, nervous, 
muscular, digestive, and reproductive systems. In the circulatory system, 
blood is pumped by the heart in a tube to the aorta, the head, and to other 
organs then enters the ostia openings along the sides of the tube back to the 
heart. The respiratory systems carries O2 to cells and takes away CO2 from 
cells through branching out to call cells of body. The nervous system consists 
of a brain receiving information from eyes, antennae, and controls the whole 
body and 2 nerve cords containing ganglia fused together to control activities 
of the segment without the help of the brain. insect muscular system is made 
up of a 
few thousand samll but string muscles allowing the insect to carry objects 
heavier than it. The digestive system is basically a long tube where food 
enters the mouth to the crop where it is stored, gizzard where it is grinded, 
stomach where it is digested, then the undigested parts and wastes are moved 
to the intestine, colon then released at the anus. And in the reproductive 
system, a new individual is produced sexually when the female eggs produced in 
the ovaries united with male sperm produced in the testes.

 Both man and insect live almost everywhere, eat all kinds of food, and use 
all kinds of materials to build homes so they constantly live in conflict. 
Some insects seriously affect man's health and are parasitic on man and other 
animals. insects that feed on human or animal blood can carry disease in their 
salivary juices and spread the disease to other animals. Many insects irritate 
us without disturbing our health. Some bite and sting, and some people are 
allergic to them and some insects are injurious to our agricultural crops, 
food products, clothing, and wooden buildings. So far man has only partial 
success in defending against insects. But some insects species are beneficial 
to man. The honey bee, for example, supplies us with honey and the silkworm 
supplies us with silk. So bugs really aren't that bad.

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