390 likes | 747 Views
Lecture 8: Manipulation of Development, Aging and Death. Now playing: Weird Al Yankovic “I Think I’m a Clone, Now”. Goals:. 1. Define fertilization, conception, cleavage, implantation, embryo, fetal period, birth, maturation, aging & death.
E N D
Lecture 8: Manipulation of Development, Aging and Death Now playing: Weird Al Yankovic “I Think I’m a Clone, Now”
Goals: 1. Define fertilization, conception, cleavage, implantation, embryo, fetal period, birth, maturation, aging & death. 2. Understand ethical issues of abortion and euthanasia: naturalism, deism, theism, pantheism & nihilism. 3. Apply topics to life, science & heath care. Assignment: Read: chapter 15, 38 (In B/C 26) Websites: http://www.religioustolerance.org/euthanas.htm http://www.religioustolerance.org/abortion.htm http://www.religioustolerance.org/cloning.htm http://www.religioustolerance.org/emb_rese.htm http://prorev.com/genetic.htm http://www.indiana.edu/~engs/cbook/chap2.html http://fertilethoughts.net/faq/asrm/screen.html http://www.leaderu.com/orgs/narth/1995papers/satinover.html http://www.pbs.org/newshour/forum/april98/iq07.html http://hem.passagen.se/nicb/god_ethics.htm
What are some of the scientific, ethical, moral and societal challenges associated with Fertilization, Development, Aging and Death? Birth Control, fertilization, abortion, aborted fetal products, stem cells, manipulation of life, manipulation of death…
Key Terms • Cloned human embryo • Embryonic stem cell • Blastula, Blastocyst • Pluripotent • Karyotype • How does cloning work: • Where does the egg come from • Where does the DNA come from • How many copies of each chromosome
Evidence of a Pluripotent Human Embryonic Stem Cell Line Derived from a Cloned Blastocyst Woo Suk Hwang et al. 1 College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea; • Somatic cell nuclear transfer. • Pluripotent embryonicstem cell line • Cloned human blastocyst. • Capable of differentiating into embryoidbodies • Containingcell derivatives from all three embryonic germ layers • Capable of continuous proliferation for >70 passages • Cells maintain normal karyotypes
Cortical Granules Acrosome Mitochondria Tail Egg Corona Radiata Zona Pellucida Fertilization- The Big Event Egg Sperm Nucleic Acid: DNA
inner cell mass oviduct uterus FERTILIZATION ovary IMPLANTATION endometrium Fig. 39.21a, p. 666
Start of amniotic cavity Start of embryonic disk Trophoblast (surface layer of cells of the blastoyst) Endometrium Blastocoel inner cell mass Start of yolk sac Uterine cavity DAYS 6-7 DAYS 10-11 Chorionic cavity Shorion Shorionic villi Blood-filled spaces Smniotic cavity Start of chorionic cavity Connecting stalk yolk sac DAY 14 DAY 12
Meiosis Nucleus of a diploid (2n) Reproductive cell with two pairs of homologous chromosomes OR Possible alignments of the two homologous chromosomes during metaphase I of meiosis A A a a A A a a B B b b b b B B A A a a A A a a The resulting alignments at metaphase II: B B b b b b B B B B b b b b B B allelic combinations possible in gametes: A A a a A A a a 1/4 AB 1/4 ab 1/4 Ab 1/4 aB Fig. 10.8, p. 158
FERTILIZATION Oviduct Ovary OVULATION Uterus Opening of cervix Zona pellucida Vagina Follicle cell Granules in cortex of cytoplasm Sperm enter vagina Nuclei fuse
Growth Increase in number, size and volume of cells Development Emergence of specialized, distinct body parts, according to genetic programming and the environment of the uterus Age of survivability Age at which a fetus can survive outside the mother: currently 19 weeks 14 weeks 5 months 6 months Fetal Period Fetus: third month of human development until birth
Facts about American Abortions Reasons for Aborting: • 92% of all American abortions are for “social • engineering” or “quality of life” reasons. • 8% of all American abortions are for the so called • “hard cases”: rape, incest, health of the baby • or threat to the health of the mother. Source: The Allan Guttmacher Institute
When should abortion be legal in America? Source: Gallup/ CNN/ USA Today Jan, 2003 • Abortion should be illegal in all cases = 18% • Abortion should be legal only to save the life of the mother = 85% • Abortion should be legal to save the life of the mother only in cases of rape or incest = 77% • Abortion should generally be legal during the first trimester? • 66% Yes 29% No • Abortion should generally be legal during the second trimester? • 25% Yes 68% No • Abortion should be legal at anytime during a woman’s pregnancy • for any reason = 10%
Birth What is human? 1:18,000 births = Anencephalous (born without a brain) -GENES -CELL LINES -Stem Cells -BODY PARTS Commercialization of human parts
“Participatory Evolution” A Banal Avarice: In private industry’s hands with a motive to profit where will we stop? • Abortion • Testing • Marketing human genes? • Selling aborted products? • Wall Street trading in body parts from cloned anencephalic babies? Human Morality $
Population Control Lobby Because teens in other developed countries receive more education about sexuality and have more access to contraception and family planning services, they have much lower rates of pregnancy and abortion. For example, in the Netherlands, where teenage sexual activity is about the same as in the U.S., pregnancy rates are only one-ninth those of the United States.
What about birth defects? Frequency Of Types Catastrophe survivors? Birth Defect Types Human Population less risk of cancer? Morals, ethics & $… With the capacity to fix them, what about those who can’t afford the fix? If life science can market 20,000 tests, who wouldn’t want them? What happens to evolution when man starts manipulating life/death? Trisomy 21 carriers = apparently never get cancer In the 1930’s and 40’s, we convinced ourselves to sterilize those with defects!
How do you know what is right? • Is this procedure immoral, banal • avarice, participatory evolution or • responsible health care? • Where does right and wrong • come from in health care & who • decides? • Does everyone everywhere • have access to this technology; • why or why not? • Who controls the technology, • and how was control awarded? • Follow the $ & the folks that profit?
BioethicsDestroying Embryos is the Basis of the Ethical Debate Questions: • What is the moral status of the developing embryo • Is this simply tissue or is it something more? • Is this a twin? The genetic make up is identical • What is the purpose? • Making donor tissue? • Making a baby? • Is regenerative medicine ethical?
Human Lizards and salamanders can regenerate limbs and tails } -Burns Regeneration -Scars …perfectly! HOW????? Maturation …but imperfect
Definition Death • Ethics
Definition of Death { Brain waves Sinus rhythm 1. Absence of life 2. Lack of sensation 3. No growth, reproduction or metabolism 4. Without normal function 5. Genetic inability to function 6. Lacking the “spirit” or “essential spark of life”
Aging Environmental resistance Master genes Programmed death -master genes = fountain of youth Free radicals and superoxide dismutase (SOD)
Environmental resistance contributes to aging: • Wrinkles • Joints -Connective tissue and somatic cells decline in regeneration rates • Skin elasticity
Euthanasia Contemporary moral standards Euthanasia Scientific ideology What’s your stand? In the Greek language, eu means "good" and thanatos means "death". The meaning of the word is "the intentional termination of life by another at the explicit request of the person who dies." • Some terminally ill patients are in severe pain and experience an intolerably poor quality of life • The cost of keeping terminal patients alive diverts money, medicine and caregivers’ availability to non-terminal patients. • The financial burden for patients’ care upon their families may be prohibitive of adequate care
Master genes When secondary sex characteristics begin to develop, signals are sent from neurosecretory cells Master genes turn on and you’re programmed to die Are master genes the key to the fountain of youth?
Free radicals and Superoxide Dismutase (SOD) Age spots Memory Loss Cataracts Arthritis Alzheimer's disease When a chemical bond is broken: the electrons can stay together (both go to one of the atoms and the other atom gets none) • electrically charged (the atom with the electrons is negatively charged and the one without the electrons is positively charged) and generally stay together or they can split up (one electron goes to each atom). • ion • free radicals (molecules with an unpaired electron). • highly energetic and seek out other electrons with which to pair and steal electrons in the process Antioxidants (also known as free radical scavengers) such as Vitamin E, Vitamin C, beta-Carotene and Selenium function by offering easy electron targets for free radicals.
Ethics & Metaphysical Beliefs: Worldviews 1. Naturalism 2. Deism 3. Theism 4. Pantheism 5. Nihilism Some basic philosophical beliefs...
1. Closed system Naturalism 2. materialism 5 senses, atomic particle nature of all things 3. we don’t exist as immaterial selves, either mental or spiritual, that control behavior--we are only matter 4. Life = blind chance, everything we are and do is included in the material continuum whose most basic elements are those described by physics 5. Life = no purpose 6. Man’s conscience = physiological/psychological response -- knowledge about what exists and about how things work is best achieved through the sciences, not personal revelation or religious instruction When we die, what's next is nothing; death is an abyss, a black hole, the end of experience; it is eternal nothingness, the permanent extinction of being
Deism 1. design is found throughout the known universe and this realization brings Deists to a sound belief in a Designer or God. 2. God created the universe 3. God did stuff and then left it to run on its own. 4. “The Blind Watchmaker” 5. Anti-supernaturalism: Miracles do not occur 6. “the Bible, though it contained important truths, was not divinely inspired; many important Christian theological tenets -- the divinity of Christ, the doctrine of the Trinity, and the theory of atonement for sins -- were the results of superstition or invention and had to be rejected.”
Theism • Design found throughout the known universe and this • realization brings Theists to a sound belief in a God. 2. Open system or Universe 3. God was active creator and sustains current life and the Cosmos 4. Miracles occur, but are not disruptions in nature they are synchrony in nature. 5. God communicates with man; moral realism: what is right and wrong is independent of what any person thinks is right and wrong. 6. Man is unique in creation
Pantheism 1. universe = ever-changing totality of being, past, present and future; self-creating, self-organizing, and inexhaustibly diverse 2. All matter, energy, and life are an interconnected unity of which people are an inseparable part 3. People should cherish, revere and preserve in all life’s magnificent beauty and diversity (human and non-human) 4. moral realism: believe it is an objective fact that some kinds of actions are ethically right and others wrong, and what is right and wrong is independent of what any person thinks is right and wrong. 5. God is identical with the real world. God is all and all is God. God does not transcend reality but is imminent in reality, or rather, all reality is in God. Death is a return to nature of our elements. Our actions, our ideas and memories of us live on in the world, according to what we do in our lives.
Nihilism 1. The belief that all values are baseless and that nothing can be known or communicated 2. “Death is nothing.” 3. “There is no God.” 4. “I could be wrong.” Just tell me what a disordered universe would look like. I can't imagine it would be any different than this one
Life is pleasant. Death is peaceful. It's the transition that's troublesome. --Isaac Asimov(1920-1992) Russian/American Science-Fiction Author, awarded 7 Hugo Awards, 3 Nebula Awards (among others), 14 honorary doctorates, 1997 Science Fiction and Fantasy Hall of Fame inductee
All things are connected like the blood which unites one family. Whatever befalls the earth befalls the sons of earth. Humans did not weave the web of life. He is merely a strand of it. Whatever he does to the web he does to himself. All there is, is the Cosmos. All conditioned things are subject to decay. Strive with diligence. God is dead and therefore, man is free. There are innumerable definitions of God because His manifestations are innumerable. There are only two ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle. Death is nothing else but going home to God, the bond of love will be unbroken for all eternity. I am the way, the truth and the life, no one comes to the Father but through me.
All things are connected like the blood which unites one family. Whatever befalls the earth befalls the sons of earth. Humans did not weave the web of life. He is merely a strand of it. Whatever he does to the web he does to himself. – Chief Seattle All there is, is the Cosmos. –Karl Sagan All conditioned things are subject to decay. Strive with diligence. -- Buddha God is dead and therefore, man is free. -- Neitzche There are innumerable definitions of God because His manifest-ations are innumerable. -- Mahatma Gandhi There are only two ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle. -- Albert Einstein Death is nothing else but going home to God, the bond of love will be unbroken for all eternity. -- Mother Teresa I am the way, the truth and the life, no one comes to the Father but through me. –Jesus Christ