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When several large bills come through the post together ? Quoting rayilynlee <[log in to unmask]>: > Medical Controversy - When Does Life Begin? > May 10, 2009 | By Sajid Surve, DOcloseSajid Surve, DO Name: Sajid Surve > Site: http://brainblogger.com > > About: Dr. Sajid Surve is a physiatrist, acupuncturist, and osteopath who > specializes in musculoskeletal medicine and integrative medicine. | > > One of the most contested questions in history is a seemingly simple one: > When does life begin? Different cultures and societies have battled to > answer this question, and to date no consensus has been reached. Of course, > the answer to this question has profound ethical, legal, moral, and > philosophical implications. As the United States debates the merits and > pitfalls of topics like embryonic stem cell research and abortion, the > arguments for the beginnings of life have found themselves renewed. Along > the timeline from preconception through birth and beyond, there are several > stops where one group or another has drawn a line in the sand and proclaimed > > that life has officially begun. In the interest of providing some clarity on > > this issue, let us examine the rationale behind why these groups picked > their points. As a reference, a textbook on developmental biology will > provide some framework. > > Preconception > The earliest stopping point is held by many members of the Catholic Church, > with their proclamation that "every sperm is sacred." The held rationale is > that every sperm has the possibility to fertilize an egg, become implanted, > and eventually grow into a human being. Since God's charge is to go forth > and procreate, any type of hindrance to that process such as the use of > condoms or birth control pills are interfering with God's plan and therefore > > not allowed. > > Conception > The greater religious community generally view the "moment of conception" as > > the standard for when life begins. However, the definition of conception is > subject to variability. Some take the word conception to actually mean the > act of ejaculation. Others consider conception to be the process of > fertilization. Still others consider the fusion of genetic material into a > new set of chromosomes to be meant by conception. The problem with any of > these definitions is that the process is not instantaneous. From the time of > > ejaculation, sperm take 7 hours before they become active and able to > fertilize an egg. Once the sperm meets the egg, a chemical cascade begins > and the sperm begins to bore its way through the egg, which may take up to > an hour. Once the sperm actually enters the egg, it's another 12 hours > before the sperm DNA makes its way to the egg's DNA, and then another 24 > hours for the restructuring and packaging process of new chromosomes. All > told, the "moment of conception" could take anywhere from 2-3 days to > complete. > > Gastrulation > Another argument that is raised against the "moment of conception" line of > thinking is the twinning argument. Once the genetic material is completely > packaged together, a new individual is created. However, for as long as > 12-14 days afterward, the embryo can split into twins or more multiples. > That process would create more than one individual with identical genetic > material from the same moment of conception. To account for this > discrepancy, some argue that life begins at gastrulation, which is when the > window has closed, the embryo has implanted in the uterus, and is now > committed to grow into one human being. Supporters of this theory would > therefore support stem cell research, which harvests embryos that have > neither the intention nor ability to be implanted into a uterus. > > Week 8 > The eighth week of pregnancy is a special one, because at this point the > precursors to all organs have been formed. Philosophers therefore argue that > > with the beginnings of a brain, the fetus now has the ability to think and > react, and that marks the onset of life. Opponents argue that the > rudimentary nervous system is not functional at 8 weeks, and the fetus > cannot process information or move in response to a stimulus, therefore not > making the fetus alive. > > Quickening > Those same groups which argue against the week 8 model suggest that life > begins with the "quickening," which is when the fetus begins to exhibit > voluntary movement inside the womb, usually around 14-16 weeks. At this > point the fetus is able to react to external stimuli, which is held as the > standard for life. > > Week 20 > Although the fetus can move at week 14, the movements are little more than > jerky reflexes. They are not driven by higher cortical functioning. > Therefore, another school of thought is that life begins at week 20, when > the thalamus is completely formed. The thalamus is the relay center of the > brain, and helps to connect the cerebral cortex to the spinal cord and > peripheral nerves. > > Week 25 > A sizable contingent would assert that life begins at 25 weeks. The > rationale for this starting point is based on our definition of death. The > definition of death is not disputed, and is considered the time when > electroencephalography (EEG) activity ceases. EEG measures brain activity > and must demonstrate regular wave patterns to be considered valid. > Therefore, by this rule the onset of life would be the time when fetal brain > > activity begins to exhibit regular wave patterns, which occurs fairly > consistently around week 25. Previous to that time, the EEG only shows small > > bursts of activity without sustained firing of neurons. > > Birth > Perhaps the second-most frequently held conviction is that life begins at > the time of child birth. In Jewish Talmudic Law, for example, the writing > states that once the head of the child is delivered it cannot be touched and > > is granted equal rights to life as the mother. Other religious groups > maintain that the soul is delivered to the newborn with their first breath > of air. > > Self-consciousness > A minor group of philosophers maintain that the criterion for human life is > self-consciousness, or self-awareness, which does not occur until well into > childhood. This group believes that abortion is morally equivalent to > infanticide, and that both are condonable under certain circumstances. Their > > viewpoint is extreme, and has generally been rejected by mainstream > ethicists and theologians. > > While this accounting is by no means comprehensive, and perhaps > oversimplifies some concepts for the purpose of clarity, let it serve as a > starting point for obtaining more information. With debate on this topic > wide open, and no clear answers in sight, the best hope is to understand all > > viewpoints and draw an informed conclusion as to when life begins. > > Reference > Gilbert, Scott F. DevBio, a Companion to Developmental Biology, Eighth > Edition. Sinauer Associates Inc., March 2006. Chapter 2, subsection 1. > > Rayilyn Brown > Director AZNPF > Arizona Chapter National Parkinson Foundation > [log in to unmask] > > ---------------------------------------------------------------------- > To sign-off Parkinsn send a message to: mailto:[log in to unmask] > In the body of the message put: signoff parkinsn > ---------------------------------------------- This mail sent through http://www.ukonline.net ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn