Informative Speech : Science behind Human Aging - how the cell againg - effect o
ID: 3479299 • Letter: I
Question
Informative Speech : Science behind Human Aging - how the cell againg - effect of outer factors - how to improve DNA repair - againg well
An informative presentation teaches the audience something and increases listener’s understanding, awareness, or sensitivity to your topic”.
6-8 minutes in length speech
The topic must be adequately researched and covered (narrowed focus).
Clear thesis statement that is developed in ~3 main points, with main points arranged in one of the organizational patterns covered in class.
Each main point must be supported with a variety of supporting materials (e.g. news articles, expert testimony, statistics, etc.). The speech should reflect responsible, objective knowledge of your topic.
Submit speech and bibliography with a minimum of 5 references that will be cited in your presentation. - Use MLA stle
Explanation / Answer
Scince Behind Human Aging:-Physiological changes that take place in the human body leading to senescence, the decline of biological functions and of the ability to adapt to metabolic stress. In humans the physiological developments are normally accompanied by psychological and behavioural changes, and other changes, involving social and economic factors, also occur.
Aging begins as soon as adulthood is reached and is as much a part of human life as are infancy, childhood, and adolescence. Gerontology (the study of aging) is concerned primarily with the changes that occur between the attainment of maturity and the death of the individual.
The biological-physiological aspects of aging include both the basic biological factors that underlie aging and the general health status. Since the probability of death increases rapidly with advancing age, it is clear that changes must occur in the individual which make him more and more vulnerable to disease. For example, a young adult may rapidly recover from pneumonia, whereas an elderly person may die.
Physiologists have found that the performance of many organs such as the heart, kidneys, brain, or lungs shows a gradual decline over the life span. Part of this decline is due to a loss of cells from these organs, with resultant reduction in the reserve capacities of the individual. Furthermore, the cells remaining in the elderly individual may not perform as well as those in the young. Certain cellular enzymes may be less active, and thus more time may be required to carry out chemical reactions. Ultimately the cell may die.
How The Cell Aging:- Cells go through a natural life cycle which includes growth, maturity, and death. This natural life cycle is regulated by a number of factors, and the disruption of the cycle is involved in many disease states. For example, cancer cells do not die the way normal cells do at the end of their life cycle.
Cellular senescence is part of the normal aging of a diploid cell where it loses its ability to divide. Some sources suggest that senescence occurs via programmed gene expression changes, or that it is a result of an accumulation of DNA double strand breaks or toxins. Cellular senescence is easily detected by measuring Senescence Associated ß-galactosidase (SA-ß-gal), a hydrolase enzyme that catalyzes the hydrolysis of ß-galactosidase into monosaccharides only in senescent cells.
Programmed cell death happens naturally as a result of a cascade of signals within the cell itself. The most common form of programmed cell death, apoptosis, plays an important role in population control and prevents massive cell growth which could lead to a possible tumor. In embryogenesis, apoptosis allows the digits of our fingers and toes to acquire their normal shape that is instead of having webbed hands and feet. The cell is ultimately triggered to commit suicide when the correct internal signals are activated.
High-Frequency Radiation
Radiation in this context refers to the emanations of particles or electromagnetic energy from radioactive decay or from man-made processes such as x-ray photography of the human body.
In non-massive amounts, such radiation damages individual cells. Damaged cells may be impaired in their function (such as a muscle cells losing their ability to contract). As time passes and the number of impaired cells increases, the entire muscle (in this example), which is composed of a very large number of individual cells, becomes impaired in its general functioning.
Free Radicals
Free radicals are molecules that are ingested or produced within the body that combine haphazardly with the molecules of living cells. Free radicals damage the cells of all the bodily organs —especially the heart and arteries.
Free radicals are formed in foods during processing, storage, or cooking. Fats, especially unsaturated ones, are subject to free-radical formation when they are exposed to heat, light, or oxygen. To avoid the introduction of free radicals into the body, you should avoid damaged fats. Damaged fats include not only foods fried in vegetable oil but bottled oils, most of which have been exposed to processing, heat, light, and oxygen
Nutrition
Another manner in which cells are damaged is by not receiving the nutrients required for their functioning, repair, or reproduction. Every cell in our body requires a supply of oxygen, vitamins, minerals, amino acids, sugar, etc. Every cell also requires that waste products such as carbon dioxide be eliminated from it. It is not sufficient to eat a “well-balanced diet.” The food must be digested, absorbed into the bloodstream, and routed to the appropriate cells. Optimal digestion and absorption are unlikely when foodstuffs are haphazardly consumed without regard to their mode of digestion and the effect of one upon the digestion of the other. Full discussion of this topic is beyond the scope of this book but can be found in Herbert Shelton’s excellent book on combining foods.
Insufficient Sleep
There are many important restorative effects that occur during sleep. During the day, our body is under the constant pull of gravity in a vertical direction. Gravity compresses the spine and requires the heart and vascular system to pump blood against its pull. When sleeping, which is usually done lying down, the heart and vascular system can rest, and the spine can regenerate. Of course, merely lying down will give similar benefits, but there are other benefits that only occur during sleep. For example, certain hormones such as growth hormone and cortisol are secreted only during sleep. Also, the brain and nervous system go into a state that does not occur while awake. Many of the benefits of sleep occur during meditation, and those who meditate regularly often require much less sleep.
Excessive Sexual Activity
For the male, excess sexual activity is not without a cost. Sperm requires energy and nutrients for its production, and engaging in excessive sexual activity tends to stimulate a larger than normal production of sperm. Moreover, the production of seminal fluid requires nutrients that are lacking in the diets of many. For example, the secretion of the prostate contains relatively large amounts of zinc, and unless one eats a diet primarily consisting of natural foods or takes mineral supplements, that mineral is not easy to get.
Poisons
A poison is any substance that has an adverse physiological relationship to the growth and nutrition of the cells of the body. There are a multitude of poisons that harm us and are, consequently, to be avoided. Among these poisons are artificial flavors, artificial colors, preservatives, polluted air, polluted water, damaged fats, alcohol, caffeine, mercury-amalgam dental fillings, inoculations, most pharmaceuticals, and products of putrefaction in the gut.
Insufficient, Improper, or Excessive Exercise
Here is a case where the aging process is not so much a result of age but, rather, the number of years of lack of proper use of the body. For example, flexibility continually decreases with lack of movement that involves regularly using muscles through their full range, and increases with proper “stretching.”
How to improve DNA repair - againg well:-
DNA is a precious molecule. It encodes vital information about cellular content and function. There are only two copies of each chromosome in the cell, and once the sequence is lost no replacement is possible. The irreplaceable nature of the DNA sets it apart from other cellular molecules, and makes it a critical target for age-related deterioration. To prevent DNA damage cells have evolved elaborate DNA repair machinery. Paradoxically, DNA repair can itself be subject to age-related changes and deterioration. In this review we will discuss the changes in efficiency of mismatch repair (MMR), base excision repair (BER), nucleotide excision repair (NER) and double-strand break (DSB) repair systems during aging, and potential changes in DSB repair pathway usage that occur with age. Mutations in DNA repair genes and premature aging phenotypes they cause have been reviewed extensively elsewhere, therefore the focus of this review is on the comparison of DNA repair mechanisms in young versus old.
AGE-RELATED CHANGES IN MISMATCH REPAIR (MMR)
MMR removes mispaired bases resulting from replication errors, recombination between imperfectly matched sequences and deamination of 5-methyl-cytosine. DNA replication past a mismatched base pair would result in a point mutation. The MMR system is also thought to play a role in repair of oxidative damage by mechanisms that are not well understood . Several lines of evidence indicate the importance of the MMR system to the aging process. MMR is essential for maintenance of repeated sequences, as mutations in MMR genes are associated with a substantial destabilization of microsatellites, and microsatellite instability increases with aging in humans.
AGE-RELATED CHANGES IN BASE EXCISION REPAIR (BER)
Excision repair removes lesions that affect only one DNA strand, which permits excision of the lesion and subsequent use of the complementary strand to fill the gap. BER corrects small DNA alterations that do not distort the overall structure of DNA helix, such as oxidized bases, or incorporation of uracil. Excision repair is critically important for repairing base damage induced by reactive oxygen species.
AGE-RELATED CHANGES IN NUCLEOTIDE EXCISION REPAIR (NER)
NER removes short DNA oligonucleotides containing a damaged base. NER recognizes bulky lesions caused by carcinogenic compounds, and covalent linkages between adjacent pyrimidines resulting from UV exposure. NER is further classified into global genome repair (GG–NER) that occurs everywhere in the genome, and transcription-coupled repair (TCR), which removes lesions in the transcribed strand of active genes.
AGE-RELATED CHANGES IN DOUBLE-STRAND BREAK (DSB) REPAIR
A DSB is the most lethal of all DNA lesions. If unrepaired, a DSB leads to loss of chromosome segments and threatens the survival of the cell. Equally detrimental to the organism are misrepaired DSBs that destabilize the genome and lead to genomic rearrangements. Genomic rearrangements become common in aging organisms ultimately leading to deregulation of transcription (1) and malignancies.