- Big Q: Are all people created equal?
- Big Q: Is art getting better or worse?
- Big Q: Are books dead?
- Big Q: Why are 43 percent of Americans barely able to read?
- Big Q: Who's better at communicating -- men or women?
- Big Q: Are there any modern mummies?
- Big Q: Is texting the end of talking?
- Big Q: Is privacy a dying concept or the next battleground?
- Big Q: Is the Internet making us sicker?
- Big Q: What makes a good citizen?
- Big Q: Is race a social construct?
- Big Q: Can love actually kill you?
- Big Q: Should we force a cap on the U.S. population?
- Big Q: Do prisons create more criminals?
- Big Q: If the 1 percent had less, would the 99 percent really have more?
- Big Q: Are humans meant to be monogamous?
- Big Q: Can humanity counteract the damage it's done to Earth?
- Big Q: Is global warming real?
- Big Q: Is healthy food a right or a privilege?
- Big Q: What is Gender?
- Big Q: Is there a "gay gene"?
- Big Q: Are rich people smarter?
- Big Q: If you saw someone being mugged would you stop to help?
- Big Q: Can music make you smarter?
- Big Q: What role does creativity have in business?
- Big Q: Should your health be public information?
- Big Q: Can prayer heal cancer?
- Big Q: Is there life before birth?
- Big Q: Is racism hereditary? (Is there a racist gene?)
- Big Q: Would the world be different if we all looked alike?
- Big Q: Are we inherently evil?
- Big Q: Is it better to confess a lie or keep it secret?
- Big Q: Will the world end in 2012?
- Big Q: What's the first thing you'd say to an alien?
- Big Q: Is there a sixth sense?
- Big Q: Is God evil?
- Big Q: Should fast food be outlawed?
- Big Q: Why is depression becoming more common?
- Big Q: Will surgeons be replaced by robots?
- Big Q: Can we arrest aging by destroying certain cells in our bodies?
- Big Q: Is any place in the U.S. safe from Mother Nature?
- Big Q: Does the Mayan calendar predict our doom -- will the world end in December 2012?
- Big Q: Did the Mayans use multiple calendars?
- Big Q: Why did the Mayans use a 260-day calendar?
- Big Q: Will humans still look the same 10,000 years from now?
- Big Q: Can the brain solve problems while the body sleeps?
- Big Q: What impact does ocean acidification have on undersea life?
- Big Q: Would we age differently on another planet?
- Big Q: Are near death experiences just hallucinations?
- Big Q: Is fashion empowering?
- Big Q: Can playing games make us smarter?
- Big Q: Could a hacker take down the Internet?
- Big Q: Do animals have a sense of right and wrong?
- Big Q: Do clothes really make the man (or woman)?
- Big Q: Does having children make us happier?
- Big Q: Does monogamy make us happier?
- Big Q: Does quantum foam hold the keys to time travel?
- Big Q: Does the Internet make travel irrelevant?
- Big Q: Does the modern prison system work?
- Big Q: Have credit cards made us poor?
- Big Q: How does science fiction predict the future?
- Big Q: How has the Internet changed politics?
- Big Q: How is globalization changing culture?
- Big Q: Is marriage dead?
- Big Q: Is taxation stealing?
- Big Q: Is the "American Dream" really possible?
- Big Q: Is the U.S. Constitution out of date?
- Big Q: Is there an ideal form of government?
- Big Q: Is your personal information the new currency?
- Big Q: What are the odds of surviving a plane crash?
- Big Q: What does 'free speech' really mean?
- Big Q: What does it take to explore the Mariana Trench?
- Big Q: What is fashion?
- Big Q: What is the future of the book?
- Big Q: What is the future of travel?
- Big Q: Why are humans competitive?
- Big Q: Why does fashion change?
- Big Q: Why does health care in the United States cost so much?
- Big Q: How much longer will we use paper currency?
- Big Q: Is technology killing our ability to practice patience?
- Big Q: Who is the world's most powerful person?
- Big Q: Does good grammar still matter?
- Big Q: Is Internet access a right or a privilege?
- Big Q: Are we getting dumber?
Big Question: Is there life before birth?
Defining human life in relationship to birth, is one of the most controversial topics in the world today. Curiosity contributor Susan Sherwood examined the question.
Let’s use a biological perspective. Biologists look for properties that are associated with life. If they’re all present, then life exists.
Cellular organization. This exists from the get-go. Fertilization forms a single-cell zygote, which reproduces quickly and forms a blastocyst. After about 12 days, this is the basis of the embryo and placenta. At two months, the embryo is a fetus.
Growth and development. Organisms take in matter and use the energy to grow and change. Fetal metabolism turns nutrition from the mom into chemical building blocks to make new cells.
Reproduction -- creating new cells for growth and repair, and being able to produce new organisms. Fetuses are growing and can also make new cells to replace injured tissue. And fetuses can't reproduce, but they develop organs to someday make it possible.
Ability to respond to the environment. In utero, a fetus can respond to its environment.
Heredity Organisms must have a genetic system. At fertilization, the zygote has DNA from both mother and father.
At some point in development, a fetus has the biological characteristics to be called living. But rather than answer questions, this raises more. When is a fetus a separate entity from the mother? When can it be considered human?
Next, in the video below, Dr. Rudy Tanzi talks about a related question: the relationship between the brain and the soul.
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