Last week's molecule was the fatty acid synthase complex [Monday's Molecule #207]. The winner was Matt McFarlane. He should contact me by email to collect his winnings.
Today's molecule was pictured on a US stamp issued in April 2008. Can you identify the molecule? ... Be precise, there's only one correct answer and it may not be the one you think.
Email your answers to me at: Monday's Molecule #207. I'll hold off posting your answers for 24 hours. The first one with the correct answer wins. I will only post mostly correct answers to avoid embarrassment. The winner will be treated to a free lunch.
There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your email message.)
Atheists do not believe in any gods. An atheist does not claim to have proof that gods don't exist, although they do claim that most of the evidence for god(s) is wrong.
I really like the way Hemant Mehta explains this on his blog Friendly Atheist.
The House of Commons in Canada has passed a bill declaring that Canada will celebrate Pope John Paul II Day on April 2nd every year [An Act to establish Pope John Paul II Day]. It was a private member's bill introduced by Conservative Wladyslaw Lizon (Mississauga East—Cooksville). Lizon is Polish, which partly explains his admiration for the former Pope. Read what Veronica Abbass has to say about this: Tommy Douglas versus Karol Wojtyła.
Meanwhile, in Ontario, a similar bill was passed by the provincial legislature [see Blindsided on Canadian Atheist].
It's tempting to dismiss both these bills as trivial. After all, nobody really expects either government to make a big fuss about it next April 2nd. Its also tempting make excuses by recognizing that few MPs or MPPs could risk speaking out against them.
I don't think we should settle for that. The facts are revolting. Canada has set aside a special day for a foreign despot whose religious and moral views are despised by a large number of Canadians, and rejected by most Catholics. How in the world could that happen in the 21st century?
Here are five things you should know if you want to engage in a legitimate scientific discussion about the amount of junk DNA in a genome.
- Genetic Load
Every newborn human baby has about 100 mutations not found in either parent. If most of our genome contained functional sequence information, then this would be an intolerable genetic load. Only a small percentage of our genome can contain important sequence information suggesting strongly that most of our genome is junk.
- C-Value Paradox
A comparison of genomes from closely related species shows that genome size can vary by a factor of ten or more. The only reasonable explanation is that most of the DNA in the larger genomes is junk.
- Modern Evolutionary Theory
Nothing in biology makes sense except in the light of population genetics. The modern understanding of evolution is perfectly consistent with the presence of large amounts of junk DNA in a genome.
- Pseudogenes and broken genes are junk
More than half of our genomes consists of pseudogenes, including broken transposons and bits and pieces of transposons. A few may have secondarily acquired a function but, to a first approximation, broken genes are junk.
- Most of the genome is not conserved
Most of the DNA sequences in large genomes is not conserved. These sequences diverge at a rate consistent with fixation of neutral alleles by random genetic drift. This strongly suggests that it does not have a function although one can't rule out some unknown function that doesn't depend on sequence.
If you want to argue against junk DNA then you need to refute or rationalize all five of these observations.
The debate over the amount of junk in our genome is a genuine scientific debate. There are legitimate scientific points of view on both sides although the weight of evidence and logic is tilting heavily in favor of junk DNA. It looks more and more like most (~90%) of our genome is junk.
The problem with the debate is that the scientific literature is full of papers attacking junk DNA while there are very few papers promoting it. This is partly because there haven't been any new discoveries in favor of junk DNA. On the other hand, there have been quite a few discoveries showing that some small part of the genome that was thought to be junk might have a function. Even though these discoveries make an insignificant contribution to the big picture, they are often blown up out of all proportion and promoted as an end to junk DNA.
A recent paper in PLoS Genetics illustrates the problem.
Last week's molecule was N-acetylmuramic acid (MurNAc) one of the components of the polysaccharide in bacterial cell walls [Monday's Molecule #206]. The winner was Michael Florea. He should contact me by email to collect his winnings.
Today's (Tuesday's) molecule is a new addition to biochemistry textbooks because its structure was only solved a few years ago. There are plenty of hints in the figure. You have to identify the molecule AND each of the seven activities that are labelled. Bonus points for the PDB identification number and the species.
Email your answers to me at: Monday's Molecule #207. I'll hold off posting your answers for 24 hours. The first one with the correct answer wins. I will only post mostly correct answers to avoid embarrassment. The winner will be treated to a free lunch.
There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your email message.)
It's Ray Comfort and he's going to destroy Richard Dawkins. Bet you can hardly wait to see this movie. PZ Myers is in it. Read what he has to say at: Lie harder, little man.
You can read Max Andrews' blog posting at: Junk DNA Isn’t Junk. Be careful, you might find it very difficult to see the connection between this philosophy student's view of biology and anything you might recognize as real science.
It goes without saying that Max Andrews gets the Central Dogma wrong—many scientists make the same mistake. But here's a taste of what else he gets wrong.
The argument from junk DNA suggests that a designer would be maximally efficient in his use of information. There appears to be some information that does not execute or have any meaningful coding. Darwinism takes this issue and uses it as the result of the prediction that there would be left over information not being used due to natural selection and random mutation. However, it doesn’t appear that all junk DNA is actually junk.
Genome organization is patterned to be maximally informative. The overlapping codes observed are known to be evolutionarily costly, because random mutations will likely have a deteriorating effect, not an instructing role So the complex specified information entailed by any genomic region is orders of magnitude higher than previously suspected by, say, Dembski. Any seemingly random aspect of chromosome sequence arrangement is not. A case in point involves endogenous retroviruses (ERV’s). This implies that the taxonomically-specific formatting, indexing, punctuation, etc., of genomes were precisely written. Morphogenetic information is not reducible to the genotype—though it is strongly dependent upon it. Therefore, changes in DNA do not equal changes in the information that structures the body plan.
I wonder who his supervisor is? Maybe Dan or I could be external reviewer on his Ph.D. oral?
Dan Graur is fed up with journalists who don't know the difference between the "genetic code" and the sequence of a genome. He's not alone. But, unlike the rest of us, Dan has a solution. It may be a little difficult to enforce ...
See: An Artistic Inspiration for Putting an End to the Misuse of the Term “Genetic Code”.
Quite a few people think that there's going to be a serious debate about junk DNA at the SMBE meeting in Chicago next week. One of the sessions has a provocative title, "WHERE DID 'JUNK' GO?", but if you look at actual session titles it doesn't look like there's going to be much of a debate.
It's true than the session organizer, Wojciech Makalowski, advertised the session as a dicussion about junk DNA ....
Nick Matzke is going to the SMBE (Society for Molecular Biology and Evolution) meeting in Chicago next week. He's created a T-shirt for supporters of junk DNA [KEEP CALM and ASK ABOUT ONIONS].
John Mattick is a Professor and research scientist at the Garvan Institute of Medical Research at the University of New South Wales (Australia). He received an award from the Human Genome Organization for ....
The Award Reviewing Committee commented that Professor Mattick’s “work on long non-coding RNA has dramatically changed our concept of 95% of our genome”, and that he has been a “true visionary in his field; he has demonstrated an extraordinary degree of perseverance and ingenuity in gradually proving his hypothesis over the course of 18 years.”
Theme
Better BiochemistryWhile I was collecting posts on biochemistry, I came across one that I wrote almost five years ago. It was about a new record for catalytic proficiency. As you know, enzymes speed up reactions that occur naturally and spontaneously. The difference between the spontaneous rate and the rate catalyzed by an enzyme is called the catalytic proficiency.
That old post [Enzyme Efficiency: The Best Enzyme] had a nice graphic showing the spontaneous rates of some reactions that take place quickly inside a cell.
Here it is ....
And here's how the information in that 2008 post got incorporated into the latest edition of my textbook.
This is a "Theme" post where I collect all previous posts on teaching biochemistry and molecular biology.
March 22, 2015
On the handedness of DNA
March 5, 2015
Don't misuse the word "homology"
January 28, 2015
Vision and Change
January 28, 2015
Evidence-based teaching
January 15, 2015
The Nature of Science (NOS)
January 11, 2015
Why can't we teach properly?
January 8, 2015
Evolutionary biochemistry and the importance of random genetic drift
January 3, 2015
Thinking critically about the Central Dogma of Molecular Biology
December 9, 2014
On the meaning of pH optima for enzyme activity
December 9, 2014
On the specificity of enzymes
December 4, 2014
How to revolutionize education
October 20, 2014
How not to teach biochemistry
October 3, 2014
Metabolism first and the origin of life
September 11, 2014
The mystery of Maud Menten
August 8, 2014
Historical contingency and the evolution of the glucocorticoid receptor
July 28, 2014
Finding the "perfect" enzyme
Jun 2, 2014
"Flipping the classroom": what does that mean?
April 25, 2014
ASBMB Core Concepts in Biochemistry and Molecular Biology: Molecular Structure and Function
April 24, 2014
ASBMB Core Concepts in Biochemistry and Molecular Biology: Biological Information
March 21, 2014
ASBMB Core Concepts in Biochemistry and Molecular Biology: Homeostasis
March 5, 2014
The crystal structure of E. coli RNA polymearse σ70 holoenzyme
January 10, 2014
How not to teach biochemistry at memorize.com
December 9, 2013
Monday's Molecule #226
December 6, 2013
Die, selfish gene, die!
December 6, 2013
Do you understand this Nature paper on transcription factor binding in different mouse strains?
December 2, 2013
Monday's Molecule #225
November 12, 2013
David Evans Says, "Teach What the Vast Majority of Scientists Affirm as Settled Science"
November 5, 2013
Stop Using the Term "Noncoding DNA:" It Doesn't Mean What You Think It Means
October 30, 2013
Time to Re-Write the Textbooks! Nature Publishes a New Version of the Citric Acid Cycle
October 29, 2013
The Khan Academy and AAMC Teach Evolution in Preparation for the MCAT
October 29, 2013
The Khan Academy and AAMC Teach the Central Dogma of Molecular Biology in Preparation for the MCAT
October 29, 2013
The Khan Academy and the Association of American Medical Colleges (AAMC) Team Up to Teach Evolution and Biochemistry for the New MCAT
October 24, 2013
ASBMB Core Concepts in Biochemistry and Molecular Biology: Matter and Energy Transformation
October 15, 2013
ASBMB Core Concepts in Biochemistry and Molecular Biology: Evolution
October 14, 2013
Fundamental Concepts in Biochemistry and Molecular Biology
October 11, 2013
ASBMB Promotes Concept Driven Teaching Strategies in Biochemistry and Molecular Biology
Another curious aspect of the theory of evolution is that everybody thinks he understands it. I mean philosophers, social scientists, and so on. While in fact very few people understand it, actually, as it stands, even as it stood when Darwin expressed it, and even less as we now may be able to understand it in biology. Jacques Monod (1974)October 8, 2013
On the Importance of Defining Evolution
October 6, 2013
Teaching Biochemistry from an Intelligent Design Creationist Perspective
October 1, 2013
The Many Definitions of Evolution
September 30. 2013
The Problems With The Selfish Gene
September 18, 2013
Breaking News!!! Wikipedia Is Wrong! (about the Central Dogma)
September 13, 2013
Sean Carroll: 'What Is Science?"
September 13, 2013
Better Biochemistry: Teaching ATP Hydrolysis for the MCAT
September 12, 2013
Better Biochemistry: Teaching to the MCAT?
June 27, 2013
The Best Enzyme
April 16, 2013
Where Do Organisms Get Their Energy?
April 10, 2013
Spontaneous Degradation of DNA
March 18, 2013
Estimating the Human Mutation Rate: Biochemical Method
