by Dr. Jeff Schweitzer
The very foundation of our moral code is fundamentally flawed. The current code of ethics predominant in modern societies, shaped largely by divine command theory, is based on false promises of eternal salvation or threats of damnation, not on a morality inherent to the human condition. As a result, a moral vacuum has developed, creating a society with deeply-rooted destructive behavioral maladaptations. War, overpopulation, unrelenting poverty, destruction of the environment, indifference to the needs and rights of other life forms and intolerance of our fellow humans all result, to an important extent, from an obsolete religious moral code.
Human beings are not inevitable, and our brief existence is not preordained to be extended into the distant future. If Homo sapiens is to have a continued presence on earth, humankind will reevaluate its sense of place in the world and modify its strong species-centric stewardship of the planet. Our collective concepts of morality and ethics have a direct impact on our species’ ultimate fate.
That religious morality has failed is made clear by humanity’s current fate, and the sad state of the planet. Religion has had 2000 years to prove itself worthy as a guiding moral force. Yet the result of that 2000-year experiment is war, poverty, hunger and suffering across the globe as humanity consumes itself; in addition, after two millennia, we see over-population, depletion of non-renewable resources, and accelerated degradation of the environment because our current moral foundation is not suited to guide us away from that destruction.
Our inner life, our own thoughts, our acts of kindness, and our responsibility and honesty are immune to the random events in the world around us, blind to the inherent purposelessness of the universe. The world can be seen with amazing clarity upon realizing that life is not manipulated by some unseen force, but instead is guided by an individual's power to make decisions and a personal choice to be moral. There is tremendous joy in understanding that the purpose and meaning of life are self-derived.
Many of humanity’s problems originate in the hubris of imagining ourselves at the center of the universe, separate from and better than other animals. But human beings are neither special nor inevitable. As a minor branch on a vast evolutionary bush, modern humans have been roaming the earth for no more than a few hundred thousand years of the earth’s 4.5 billion year history. If the earth’s lifespan were one year, humans would come on the scene only during the last 50 minutes of the year. Ours has been a truly brief presence, barely a cameo on the stage of life, with too little time to demonstrate if the evolution of large brains is a successful strategy for long-term survival of the species.
When Charles Darwin published On the Origin of Species in 1859, he exposed the world to a momentous discovery every bit as significant and disorienting as when Copernicus discovered that the earth was not the center of the universe. For the first time in history, human beings were seen not as creatures of divine origin, but instead as a natural product of evolution, an animal like every other on the planet. Imagine yourself back in that amazing year. The day before Darwin’s book was published, you woke up thinking yourself the image of God; the next morning you realize you have the face of a monkey. Not everybody immediately embraced this rude demotion. Resistance to the idea was inevitable. But have absolutely no doubt: evolution is one of the most extraordinary, successful, thoroughly documented scientific discoveries in human history. Evolution through natural selection is an indisputable fact, just as we now know that the earth revolves around the sun.
Thanks to Darwin, natural selection allows us to understand the development of nature's diversity and complexity without resorting to divine intervention. Through Darwin’s insights, we can understand that life on earth began as a natural event, and that evolution is a random process with no direction or drive. The male peacock would probably agree that any rational design would have relieved him of the burden of a ridiculously large tail, which leaves him vulnerable to predation. But because natural selection is uncaring, the poor bird now has a tail just big enough to attract painfully picky females (something to think about the next time you are pumping iron at the gym), and just small enough to make the competing male next door a greater temptation as somebody’s lunch.
Perhaps unwittingly referring to bacteria, Mathew 5:5 says that “Blessed are the meek, for they will inherit the earth,” and indeed they shall. For regardless of the fate of humanity, bacteria will survive. Bacteria can easily live without us, but we would die quickly without them. If we were able to kill every bacterium in our body, we would be dead within a month. It is the height of folly to claim that evolution was driven toward humans anymore than toward any other living being. Humans are nothing but a short-lived biological aberration, with no claim to superiority. If evolution had a pinnacle, bacteria would rest on top. When the human species is a distant memory, bacteria will be dividing merrily away, oblivious to the odd bipedal mammal that once roamed the earth for such a brief moment in time. Our claims to superiority and our self-promotion to the image of god are simply embarrassing in the face of the biological reality on the ground. There is a loss of credibility when you choose yourself for an award.
The human brain is extraordinarily adept at posing questions, but simply abhors the concept of leaving any unanswered. We are unable to accept “I don’t know” because we cannot turn off our instinct to see patterns and to discern effect from cause. We demand that there be a pattern, that there be cause and effect, even when none exit. So we make up answers when we don’t know. We develop elaborate creation myths, sun gods, rain gods, war gods, and gods of the ocean. We believe we can communicate with our gods and influence their behavior, because by doing so, we gain some control, impose some order, on the chaotic mysteries of the world. By making up answers to dull the sting of ignorance, we fool ourselves into thinking we explain the world. Religion was our first attempt at physics and astronomy.
The idea of powerful gods controlling each important aspect of our lives would not by itself be satisfying. We want to put a face to the power; we want to be familiar with the deities that control our fate; we want to know them so that we can communicate with them and solicit their interventions. We are all Dorothy in the Wizard of Oz, seeking to reveal the nature of god, hoping to strike up a conversation with whoever is in charge. By no coincidence then do our gods take on human form, usually idealized. Male gods are typically buff, in great shape, with washboard abs and thick biceps, while their female counterparts conform to the ideas of beauty at the time, usually in all cases sporting large breasts.
Advances in science, which explain the mysteries of nature’s wrath, remove the need for multiple gods of rain, sun and harvest. If we know the sun is a star sustained by thermonuclear reactions, we need not invoke a sun god. If we know that rain is caused by evaporation and condensation, we can discard our rain god. We understand that thunder is caused by lightning as a consequence of atmospheric ionization, relegating Thor to the pantheon of gods now myth. As gods are the child of ignorance, knowledge is a lethal potion strong enough to kill the most powerful force.
We will show that morals are not derived from religion, nor god’s grant of free will, but instead arise from inherent characteristics embedded in human nature as a consequence of our sociality. What we view as moral behaviors – kindness, reciprocity, honesty, respect for others – are social norms that evolved in the context of a highly social animal living in large groups. The evolution of these social norms enabled a feeble creature to overcome physical limitations through effective cooperation. Morality is a biological necessity and a consequence of human development. Religion, however, has masked and corrupted these natural characteristics with a false morality that converts intrinsic human benevolence and generosity into cheap commodities to be purchased with coupons for heaven. Good behavior is not encouraged as a means of advancing our humanity, but instead is enforced with threats of eternal damnation.
About Jeff Schweitzer
He is the Author of the upcoming book Beyond Cosmic Dice – Moral Life In A Random A World. Dr. Schweitzer served at the White House for the Clinton Administration
Working under President Clinton, Dr. Schweitzer was assigned to provide scientific and technological policy advice and analysis for the President of the United States, Vice President Al Gore and the Director of the OSTP, and to coordinate the U.S. government's international science and technology cooperation (working with the president's cabinet and 22 technical agencies) in countries throughout the world. Visit his website @ www.jeffschweitzer.com
Jamie Hale
Thursday, June 25, 2009
Tuesday, June 16, 2009
Introduction to Skeptical Thinking
By Jamie Hale
I recently presented at the Annual JP Fitness Summit in Kansas City. The Summit features some of the top minds in the fitness industry. Topics include any and everything fitness and nutrition related. My presentation addressed a topic that was foreign to the summit. My topic was Fitness Skepticism. How to apply skepticism to the fitness industry? Some of the participants seemed to have a hard time with this line of thought. Skepticism is rarely if ever mentioned in the popular fitness literature. Learning to question and look for evidence could save fitness enthusiasts a great deal of time, money, and embarrassment. When someone like Alan Aragon (nutritionist & author of Girth Control) comes along and destroys your fiction based nutrition protocol you may be a little embarrassed. Especially if you have been working in the industry for a decade.
Before attending the summit I sent my keynotes to a colleague to see if he had any further suggestions on what I should present. He was impressed and told me this information would be excellent to present as an introduction to skepticism to any group not just fitness professionals. Below are my keynotes I used for the presentation.
Seminar Fitness Skepticism: Key Notes
The Fitness Skeptic (Skeptic is derived from the Greek skeptikos, which means "inquiring" or "to look around) applies reason to any and all ideas promoted by the fitness industry or ideas promoted by anyone making fitness claims. Requires evidence before accepting claims. Explain difference between skeptic and cynic.
What is a cynic? Cynics are distrustful of any advice or information that they do not agree with themselves. Cynics do not accept any claim that challenges their belief system. While skeptics are open-minded and try to eliminate personal biases. Cynics Negative views and are not open to evidence that refutes their beliefs. This can lead to dogmatism.
Dogmatism: authoritarian approach to ideas which emphasizes strict adherence to doctrine over rational inquiry. Opposes independent thinking and reason.
The word dogma is derived from a Greek phrase meaning “that which seems to one, opinion or belief”
Skepticism is a key part of science. Science way of thinking, basically way of analyzing information with idea of testing claims. Ideas on science…………
Make use of scientific method
No precise definition for scientific method but in general most agree with the following:
The following is an excerpt from Why People Believe Weird Things (Shermer 1997). “Through the scientific method, we may form the following generalizations:
Hypothesis: A testable statement accounting for a set of observations.
Theory: A well-supported and well-tested hypothesis or set of hypotheses.
Fact: A conclusion confirmed to such an extent that it would be reasonable to offer provisional agreement.”
Important regarding certainty
NO absolute certainty. Humans are fallible.
R.A Lyttleton (Theoretical Astronomy Pro) suggests bead model of truth
This model depicts a bead on a horizontal wire that can move left or right. A 0 appears on the far left end 1 appears on the far right end.
The 0 corresponds with total disbelief and the 1 corresponds with total belief (absolute certainty).
Bead should never reach the far left or right end. The more that the evidence suggests the belief is true the closer the bead should be to 1. The more unlikely the belief is to be true the closer the bead should be to 0.
Important regarding Theory
To a scientist, the word theory represents that of which he or she is most certain; in everyday language the word implies a guess (not sure).
This often causes confusion for those unfamiliar with science. This confusion leads to the common statement “It’s only a theory.”
Regarding scientist vs. non-scientist
Scientist: One whose activities make use of the scientific method to answer questions regarding the measurable universe. A scientist may be involved in original research (Primary Research), or make use of the results of the research of others (termed Secondary Research.
Scientific degree does not necessarily mean scientist
Thinking gone wrong
Why do we accept so much nonsense in absence of evidence? Define faith
Anecdotes are not science
Scientific Jargon does not make a science
Bold Statements and Bold testimonials
Rumors everywhere
Correlation and causation
Emotive words
How to apply logic
Define logic: Concise English Oxford dictionary: science of reasoning, proof, thinking or inference
Structure of logical argument: 1 or more premises (facts) that argument states to lead to conclusion.
Conclusion to be valid all premises must be true
Conclusion could be true even though is it was invalid
Possible to use incorrect logic to reach a conclusion that happens to be true
Need to identify logical fallacies
Structure of argument
Prm 1: if A=B
Prm 2: and B=C
Logical connection: Then we apply (principle of equivalence)
Conclusion: A=C
Common logical fallacies
Ad hominen
Appeal to authority
Argumentum ad antiquitatem / Appeal to tradition (tradition)
Argumentum ad novitatem / Appeal to Novelty (newer is better)
Shifting the burden of proof (claimant insists you disprove)
Argument from personal incredulity (I can’t explain so it can’t be true)
Inconsistency (sometime scientist sometimes not depends on convenience)
Post-hoc ergo propter (A preceded B, therefore A caused B)
Straw man (arguing against position you created, position ez to argue against)
Cherry picking
Ultimate goal for the skeptic is to see evidence and then evaluate the evidence that supports claim. Evidence stands on it’s own merits.
Considerations when look at evidence refer Alan’s book
Ideological immune system
“In day-to-day life, as in science, we all resist fundamental paradigm change” Jay Snelson (social scientist) calls this resistance an ideological immune system. According to Snelson, the more knowledge individuals have accumulated, and the more well-founded their theories have become the greater the confidence in their ideologies.
Consequence we build up and “immunity” against new ideas that do not corroborate previous ones.
Sometimes if we have so much vested interest it is hard to change our stance on a subject
Bser or Liar
Harry G Frankfurt (Moral philosopher) distinguishes in book On Bullshit
Fitness industry questions more Bsers or Liars??
Practical skepticism
Can’t be skeptical all the time
Sometimes better to not be vocally skeptical
Refer to Riniolo’s article The Myth of Consistent skepticism
Practicing skeptical thinking
Take something you have always believed and try to look at it from other side. Gather all available data. Try to counterpoint your own belief. If faith based no need
Inconsistent Rationalist???
Rational people normally but touch touch topic rationality gone. Completely irrational with specific topics such as religion, abortion, death penalty, children etc.
One of the key points I wanted to emphasize was it’s alright to be skeptical. I pointed out the difference between a skeptic and a cynic. I also emphasized that the people that like to villanize skeptics are generally the real villains (quackos, charlatans, Type 1 supplement salesman, etc.) I was cut a little short on time (enough sitting it was time to go outside and jump into the Total Hale Workout) so I didn’t get to finish my presentation. I think the discussion proved beneficial for some while others found it useless. I received some positive feedback while also receiving negative feedback.
Practical implications for the skilled skeptic
Realize that the need to believe, and serve others, are basic human needs
In general our expectations pretty much determine what we see and don’t see (magicians take full advantage of this expectation)
Humans lie and they BS (almost always with a vested interest)
Under specific conditions hallucinations may occur in healthy people
For many people that don’t understand specific phenomena they would rather believe something than say they don’t know
Apply skepticism in a very cautious manner to particular subjects e.g. religion, abortion, death penalty etc.
Realize you can’t be skeptical 100% of the time as there are not enough hours in the day
The skilled skeptic must learn when to keep their questions to themselves if not you will have many enemies (be a Practical Skeptic)
The majority of society does not understand science nor are they interested (they want to know what to think not how to think)
Skilled skeptics understand the rules of logic, the principles of experimentation, experimental design and what constitutes scientific evidence
Human beings are fallible and have a need sometimes have a need to be right
Human beings have a strong need for certainty, security and stability
Human beings have strong social needs (although not all human beings)
Human beings have a strong need for simplicity, easily understandable answers to complex questions
Human beings like to feel important
Skilled skeptics do not make judgments based on insufficient evidence
Skilled skeptics realizes there are varying degrees of certainty but no absolute certainty
Skilled skeptics listen to other people’s ideas with an open mind
Skill skeptics understand all knowledge is tentative
Skilled skeptics are aware of their own personal bias, and aware when their skepticism turns to cynicism
Skilled skeptics habitually question their own beliefs and methods that were used to come to those beliefs
Skilled skeptics are educated on research methodology (this means at an advanced level)
Skilled skeptics avoid Hero Worship (e.g. James Randi says or Michael Shermer says, also referred to as Appeal to Authority Fallacy)
Skilled skeptics realize science does not explain everything nor does it claim to
Skilled skeptics do not fall prey to the Translation Fallacy (this fallacy occurs when the subject being discussed cannot be defined. If you can define the word or topic forget about stating your opinion.)
I recently presented at the Annual JP Fitness Summit in Kansas City. The Summit features some of the top minds in the fitness industry. Topics include any and everything fitness and nutrition related. My presentation addressed a topic that was foreign to the summit. My topic was Fitness Skepticism. How to apply skepticism to the fitness industry? Some of the participants seemed to have a hard time with this line of thought. Skepticism is rarely if ever mentioned in the popular fitness literature. Learning to question and look for evidence could save fitness enthusiasts a great deal of time, money, and embarrassment. When someone like Alan Aragon (nutritionist & author of Girth Control) comes along and destroys your fiction based nutrition protocol you may be a little embarrassed. Especially if you have been working in the industry for a decade.
Before attending the summit I sent my keynotes to a colleague to see if he had any further suggestions on what I should present. He was impressed and told me this information would be excellent to present as an introduction to skepticism to any group not just fitness professionals. Below are my keynotes I used for the presentation.
Seminar Fitness Skepticism: Key Notes
The Fitness Skeptic (Skeptic is derived from the Greek skeptikos, which means "inquiring" or "to look around) applies reason to any and all ideas promoted by the fitness industry or ideas promoted by anyone making fitness claims. Requires evidence before accepting claims. Explain difference between skeptic and cynic.
What is a cynic? Cynics are distrustful of any advice or information that they do not agree with themselves. Cynics do not accept any claim that challenges their belief system. While skeptics are open-minded and try to eliminate personal biases. Cynics Negative views and are not open to evidence that refutes their beliefs. This can lead to dogmatism.
Dogmatism: authoritarian approach to ideas which emphasizes strict adherence to doctrine over rational inquiry. Opposes independent thinking and reason.
The word dogma is derived from a Greek phrase meaning “that which seems to one, opinion or belief”
Skepticism is a key part of science. Science way of thinking, basically way of analyzing information with idea of testing claims. Ideas on science…………
Make use of scientific method
No precise definition for scientific method but in general most agree with the following:
The following is an excerpt from Why People Believe Weird Things (Shermer 1997). “Through the scientific method, we may form the following generalizations:
Hypothesis: A testable statement accounting for a set of observations.
Theory: A well-supported and well-tested hypothesis or set of hypotheses.
Fact: A conclusion confirmed to such an extent that it would be reasonable to offer provisional agreement.”
Important regarding certainty
NO absolute certainty. Humans are fallible.
R.A Lyttleton (Theoretical Astronomy Pro) suggests bead model of truth
This model depicts a bead on a horizontal wire that can move left or right. A 0 appears on the far left end 1 appears on the far right end.
The 0 corresponds with total disbelief and the 1 corresponds with total belief (absolute certainty).
Bead should never reach the far left or right end. The more that the evidence suggests the belief is true the closer the bead should be to 1. The more unlikely the belief is to be true the closer the bead should be to 0.
Important regarding Theory
To a scientist, the word theory represents that of which he or she is most certain; in everyday language the word implies a guess (not sure).
This often causes confusion for those unfamiliar with science. This confusion leads to the common statement “It’s only a theory.”
Regarding scientist vs. non-scientist
Scientist: One whose activities make use of the scientific method to answer questions regarding the measurable universe. A scientist may be involved in original research (Primary Research), or make use of the results of the research of others (termed Secondary Research.
Scientific degree does not necessarily mean scientist
Thinking gone wrong
Why do we accept so much nonsense in absence of evidence? Define faith
Anecdotes are not science
Scientific Jargon does not make a science
Bold Statements and Bold testimonials
Rumors everywhere
Correlation and causation
Emotive words
How to apply logic
Define logic: Concise English Oxford dictionary: science of reasoning, proof, thinking or inference
Structure of logical argument: 1 or more premises (facts) that argument states to lead to conclusion.
Conclusion to be valid all premises must be true
Conclusion could be true even though is it was invalid
Possible to use incorrect logic to reach a conclusion that happens to be true
Need to identify logical fallacies
Structure of argument
Prm 1: if A=B
Prm 2: and B=C
Logical connection: Then we apply (principle of equivalence)
Conclusion: A=C
Common logical fallacies
Ad hominen
Appeal to authority
Argumentum ad antiquitatem / Appeal to tradition (tradition)
Argumentum ad novitatem / Appeal to Novelty (newer is better)
Shifting the burden of proof (claimant insists you disprove)
Argument from personal incredulity (I can’t explain so it can’t be true)
Inconsistency (sometime scientist sometimes not depends on convenience)
Post-hoc ergo propter (A preceded B, therefore A caused B)
Straw man (arguing against position you created, position ez to argue against)
Cherry picking
Ultimate goal for the skeptic is to see evidence and then evaluate the evidence that supports claim. Evidence stands on it’s own merits.
Considerations when look at evidence refer Alan’s book
Ideological immune system
“In day-to-day life, as in science, we all resist fundamental paradigm change” Jay Snelson (social scientist) calls this resistance an ideological immune system. According to Snelson, the more knowledge individuals have accumulated, and the more well-founded their theories have become the greater the confidence in their ideologies.
Consequence we build up and “immunity” against new ideas that do not corroborate previous ones.
Sometimes if we have so much vested interest it is hard to change our stance on a subject
Bser or Liar
Harry G Frankfurt (Moral philosopher) distinguishes in book On Bullshit
Fitness industry questions more Bsers or Liars??
Practical skepticism
Can’t be skeptical all the time
Sometimes better to not be vocally skeptical
Refer to Riniolo’s article The Myth of Consistent skepticism
Practicing skeptical thinking
Take something you have always believed and try to look at it from other side. Gather all available data. Try to counterpoint your own belief. If faith based no need
Inconsistent Rationalist???
Rational people normally but touch touch topic rationality gone. Completely irrational with specific topics such as religion, abortion, death penalty, children etc.
One of the key points I wanted to emphasize was it’s alright to be skeptical. I pointed out the difference between a skeptic and a cynic. I also emphasized that the people that like to villanize skeptics are generally the real villains (quackos, charlatans, Type 1 supplement salesman, etc.) I was cut a little short on time (enough sitting it was time to go outside and jump into the Total Hale Workout) so I didn’t get to finish my presentation. I think the discussion proved beneficial for some while others found it useless. I received some positive feedback while also receiving negative feedback.
Practical implications for the skilled skeptic
Realize that the need to believe, and serve others, are basic human needs
In general our expectations pretty much determine what we see and don’t see (magicians take full advantage of this expectation)
Humans lie and they BS (almost always with a vested interest)
Under specific conditions hallucinations may occur in healthy people
For many people that don’t understand specific phenomena they would rather believe something than say they don’t know
Apply skepticism in a very cautious manner to particular subjects e.g. religion, abortion, death penalty etc.
Realize you can’t be skeptical 100% of the time as there are not enough hours in the day
The skilled skeptic must learn when to keep their questions to themselves if not you will have many enemies (be a Practical Skeptic)
The majority of society does not understand science nor are they interested (they want to know what to think not how to think)
Skilled skeptics understand the rules of logic, the principles of experimentation, experimental design and what constitutes scientific evidence
Human beings are fallible and have a need sometimes have a need to be right
Human beings have a strong need for certainty, security and stability
Human beings have strong social needs (although not all human beings)
Human beings have a strong need for simplicity, easily understandable answers to complex questions
Human beings like to feel important
Skilled skeptics do not make judgments based on insufficient evidence
Skilled skeptics realizes there are varying degrees of certainty but no absolute certainty
Skilled skeptics listen to other people’s ideas with an open mind
Skill skeptics understand all knowledge is tentative
Skilled skeptics are aware of their own personal bias, and aware when their skepticism turns to cynicism
Skilled skeptics habitually question their own beliefs and methods that were used to come to those beliefs
Skilled skeptics are educated on research methodology (this means at an advanced level)
Skilled skeptics avoid Hero Worship (e.g. James Randi says or Michael Shermer says, also referred to as Appeal to Authority Fallacy)
Skilled skeptics realize science does not explain everything nor does it claim to
Skilled skeptics do not fall prey to the Translation Fallacy (this fallacy occurs when the subject being discussed cannot be defined. If you can define the word or topic forget about stating your opinion.)
Sunday, June 7, 2009
Biochemistry 101
The following is an excerpt from Knowledge and Nonsense: the science of nutrition and exercise
Appendix 1: Biochemistry and Genetics
I decided to include this section for all of the biochemistry fans. Many of the terms mentioned in this section are often discussed in scientific texts and research studies. If you read much research, you may occasionally stumble across a word or phrase that you might not understand. I put together this section to help you understand some of those words and phrases. The terms are not presented in any particular order.
Element
These are the fundamental substances that make up the matter of the universe. An element is any substance that can’t be subdivided further by chemical means. Another way of saying this is that an element is composed of only one kind of atom. Examples of elements include oxygen, nitrogen, sulfur, carbon,and calcium.
Atom
This is the smallest part of an element that still retains the chemical and physical properties of that element. Atoms are composed of three types of subatomic particles.
1. Protons: These are positively charged particles found in the center or nucleus of the atom.
2. Neutrons: These are also found in the nucleus but bear no electrical charge (neutral).
3. Electrons: These particles move around the nucleus in orbits. They have a negative electrical charge. Electrons are arranged in shells around the nucleus. Each shell can contain only a finite number of electrons before a new shell must be formed. The first shell is filled when it has two electrons. The second and each
succeeding shell are filled with eight electrons.
Molecule
A molecule is the chemical combination of two or more atoms. Atoms chemically combine by interactions with their respective electron shells. Such interactions are termed bonds, and these bonds are what hold the atoms together. One of the most
important chemical bonds is the covalent bond, which is where two or more atoms share their electrons with one another. This can effectively fill all of the outer shells of the participant atoms,thereby making them extremely stable. A good example is water.
Macromolecules
Macromolecules are large molecules. Many organic molecules are characteristically large and are thus called macro. These macromolecules are usually formed from smaller repeating subunits. Macromolecules are often termed polymers, and the
subunits which compose them are termed monomers. Monomers are assembled into polymers by a special kind of covalent bond forming reaction termed dehydration synthesis or condensation. The name is due to the fact that water is always one of the products.
Hydrogen bonds
These are weak electrical attractions that occur between the hydrogen atoms in a molecule and the oxygen or nitrogen atoms in the same molecules or in separate molecules. Hydrogen bonds are important because they give macromolecules a threedimensional shape, which is critical to their proper functioning.
Basic organic compounds
Organic compounds are those which contain carbon. There are four major classes of organic compounds that are significant to organisms (carbohydrates, lipids, proteins, and nucleic acids).
Enzymes
Enzymes are protein bio-catalysts that speed up reactions but are
not altered by those reactions. Coenzymes are small organic molecules, frequently vitamins. The enormous diversity of proteins ensures that there will be adequate kinds of enzymes for each and every reaction. Each enzyme is specific for one
particular reaction. This means that each of the hundreds of reactions that occur within the cell must have its own enzyme. The types of reactions a cell can execute are dependent upon the kinds of enzymes present. There are six major classes of enzymes.
1. Oxireductases: Catalyze oxidation reduction reactions.
2. Transferases: Catalyze the movement of functional
groups between molecules.
3. Hydrolases: Catalyze the breakdown of polymers by the
addition of water.
4. Lyases: Catalyze the breakdown of molecules but not by
the addition of water.
5. Isomerases: Catalyze internal rearrangements of
molecules.
6. Ligases and synthetases: Catalyze the linkage of
molecules together.
Biological oxidations
Oxidation is a type of chemical reaction in which electrons are removed from an atom or molecule. Reduction is a type of chemical reaction in which an atom or molecule gains electrons. Oxidation and reduction always go together. It is not possible to
have electrons floating freely about. Whenever one molecule is oxidized another must be simultaneously reduced. In other words, the electron removed from one molecule must be transferred to another molecule.
Metabolism
Metabolism by definition is the sum total of all chemical reactions that occur within the cell or organism. It can be generally categorized into two subsections—catabolism and anabolism. Catabolic reactions are breakdown reactions in which
large complex molecules are reduced to smaller fragments (macromolecules are turned into micromolecules). Anabolic reactions are synthesis reactions whereby smaller molecules are joined to form larger or more energetic ones. Catabolic reactions
are exergonic (energy yielding) while anabolic reactions are endergonic (energy consuming). In the cell, catabolic reactions provide the energy necessary to drive the anabolic reactions.
Kreb’s cycle (tricarboxylic acid cycle, citric acid cycle)
Krebs cycle is a series of catabolic reactions occurring in the mitochondrial matrix. The main purpose of these reactions is the transfer of energy carried in the bonds of acetyl-CoA to electron carrier molecules. The molecules receiving the hydrogens and electrons are the coenzymes NAD+ and FAD, which transfer the hydrogens and electrons to the respiratory chain for the phosphorylation of ADP to ATP. Refer to The Biochemistry of Human Nutrition by Sareen Gropper for a detailed description of what happens in the Krebs cycle.
Thermic effect of food
The thermic effect of food (diet-induced thermogenesis) is an increase in the metabolic rate that occurs following the ingestion of food. It is thought to account for an increase in the basal metabolic rate of between 5 percent and 15 percent. The increase in metabolism is a result of increased oxidation associated with the digestion of food, absorption, transport, metabolism, and storage of energy following eating. Protein has the highest thermic effect of the three macronutrients. Carbohydrates have the next highest and fats the least thermic effect.
Nucleic acids
There are two types of nucleic acid—DNA and RNA. DNA is the largest molecule and it has two essential functions. It is the hereditary molecule containing the genetic blueprint that it transmits from generation to generation, and it regulates the
activity of the cell by controlling protein synthesis. All RNA is synthesized off of the DNA molecule. Part of the DNA unwinds and ribose, containing nucleotides, are locked into position in place of the deoxyribose nucleotides. Therefore, all RNA
represents a copy of some of the information contained in the DNA molecule.
Appendix 1: Biochemistry and Genetics
I decided to include this section for all of the biochemistry fans. Many of the terms mentioned in this section are often discussed in scientific texts and research studies. If you read much research, you may occasionally stumble across a word or phrase that you might not understand. I put together this section to help you understand some of those words and phrases. The terms are not presented in any particular order.
Element
These are the fundamental substances that make up the matter of the universe. An element is any substance that can’t be subdivided further by chemical means. Another way of saying this is that an element is composed of only one kind of atom. Examples of elements include oxygen, nitrogen, sulfur, carbon,and calcium.
Atom
This is the smallest part of an element that still retains the chemical and physical properties of that element. Atoms are composed of three types of subatomic particles.
1. Protons: These are positively charged particles found in the center or nucleus of the atom.
2. Neutrons: These are also found in the nucleus but bear no electrical charge (neutral).
3. Electrons: These particles move around the nucleus in orbits. They have a negative electrical charge. Electrons are arranged in shells around the nucleus. Each shell can contain only a finite number of electrons before a new shell must be formed. The first shell is filled when it has two electrons. The second and each
succeeding shell are filled with eight electrons.
Molecule
A molecule is the chemical combination of two or more atoms. Atoms chemically combine by interactions with their respective electron shells. Such interactions are termed bonds, and these bonds are what hold the atoms together. One of the most
important chemical bonds is the covalent bond, which is where two or more atoms share their electrons with one another. This can effectively fill all of the outer shells of the participant atoms,thereby making them extremely stable. A good example is water.
Macromolecules
Macromolecules are large molecules. Many organic molecules are characteristically large and are thus called macro. These macromolecules are usually formed from smaller repeating subunits. Macromolecules are often termed polymers, and the
subunits which compose them are termed monomers. Monomers are assembled into polymers by a special kind of covalent bond forming reaction termed dehydration synthesis or condensation. The name is due to the fact that water is always one of the products.
Hydrogen bonds
These are weak electrical attractions that occur between the hydrogen atoms in a molecule and the oxygen or nitrogen atoms in the same molecules or in separate molecules. Hydrogen bonds are important because they give macromolecules a threedimensional shape, which is critical to their proper functioning.
Basic organic compounds
Organic compounds are those which contain carbon. There are four major classes of organic compounds that are significant to organisms (carbohydrates, lipids, proteins, and nucleic acids).
Enzymes
Enzymes are protein bio-catalysts that speed up reactions but are
not altered by those reactions. Coenzymes are small organic molecules, frequently vitamins. The enormous diversity of proteins ensures that there will be adequate kinds of enzymes for each and every reaction. Each enzyme is specific for one
particular reaction. This means that each of the hundreds of reactions that occur within the cell must have its own enzyme. The types of reactions a cell can execute are dependent upon the kinds of enzymes present. There are six major classes of enzymes.
1. Oxireductases: Catalyze oxidation reduction reactions.
2. Transferases: Catalyze the movement of functional
groups between molecules.
3. Hydrolases: Catalyze the breakdown of polymers by the
addition of water.
4. Lyases: Catalyze the breakdown of molecules but not by
the addition of water.
5. Isomerases: Catalyze internal rearrangements of
molecules.
6. Ligases and synthetases: Catalyze the linkage of
molecules together.
Biological oxidations
Oxidation is a type of chemical reaction in which electrons are removed from an atom or molecule. Reduction is a type of chemical reaction in which an atom or molecule gains electrons. Oxidation and reduction always go together. It is not possible to
have electrons floating freely about. Whenever one molecule is oxidized another must be simultaneously reduced. In other words, the electron removed from one molecule must be transferred to another molecule.
Metabolism
Metabolism by definition is the sum total of all chemical reactions that occur within the cell or organism. It can be generally categorized into two subsections—catabolism and anabolism. Catabolic reactions are breakdown reactions in which
large complex molecules are reduced to smaller fragments (macromolecules are turned into micromolecules). Anabolic reactions are synthesis reactions whereby smaller molecules are joined to form larger or more energetic ones. Catabolic reactions
are exergonic (energy yielding) while anabolic reactions are endergonic (energy consuming). In the cell, catabolic reactions provide the energy necessary to drive the anabolic reactions.
Kreb’s cycle (tricarboxylic acid cycle, citric acid cycle)
Krebs cycle is a series of catabolic reactions occurring in the mitochondrial matrix. The main purpose of these reactions is the transfer of energy carried in the bonds of acetyl-CoA to electron carrier molecules. The molecules receiving the hydrogens and electrons are the coenzymes NAD+ and FAD, which transfer the hydrogens and electrons to the respiratory chain for the phosphorylation of ADP to ATP. Refer to The Biochemistry of Human Nutrition by Sareen Gropper for a detailed description of what happens in the Krebs cycle.
Thermic effect of food
The thermic effect of food (diet-induced thermogenesis) is an increase in the metabolic rate that occurs following the ingestion of food. It is thought to account for an increase in the basal metabolic rate of between 5 percent and 15 percent. The increase in metabolism is a result of increased oxidation associated with the digestion of food, absorption, transport, metabolism, and storage of energy following eating. Protein has the highest thermic effect of the three macronutrients. Carbohydrates have the next highest and fats the least thermic effect.
Nucleic acids
There are two types of nucleic acid—DNA and RNA. DNA is the largest molecule and it has two essential functions. It is the hereditary molecule containing the genetic blueprint that it transmits from generation to generation, and it regulates the
activity of the cell by controlling protein synthesis. All RNA is synthesized off of the DNA molecule. Part of the DNA unwinds and ribose, containing nucleotides, are locked into position in place of the deoxyribose nucleotides. Therefore, all RNA
represents a copy of some of the information contained in the DNA molecule.
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