Thursday, January 29, 2009

An Excerpt

In regard to our study of cell's flagella and cilia...

"...as biochemists have begun to examine apparently simple structures like cilia and flagella, they have discovered staggering complexity, with dozens or even hundreds of precisely tailored parts. It is very likely that many of the parts we have not considered here are required for any cilium to function in a cell. As the number of required parts increases, the difficulty of gradually putting the system together skyrockets, and the likelihood of indirect scenarios plummets. Darwin looks more and more forlorn. New research on the roles of the auxiliary proteins cannot simplify the irreducibly complex system. The intransigence of the of the problem cannot be alleviated; it will only get worse. Darwinian theory has given no explanation for the cilium or flagellum. The overwhelming complexity of the swimming systems push us to think it may never give an explanation."

Quoted from Michael J. Behe in his book, Darwin's Black Box

Tuesday, January 27, 2009

One piece of scientific evidence, among many, against Evolution.

In the current module we're reading, it discussed how there is a lot more evidence against evolution than evidence for it. Let's take the archaeopteryx as one example...  

They talked about how evolutionists took the archaeopteryx as a "missing link" between reptiles and birds just because the prehistoric bird had claws protruding from it's wings, and teeth in it's beak.  That was the only two things that they related of being closely connected to reptiles.  Everything else proved to be from pure bird ancestry.

Later on as more bird fossils were being discovered, a big amount of birds that had teeth and claws began appearing.  This showed that their old reason for the archaeopteryx being a "missing link" is not really proof at all since there were other birds with these same features.

Along with this argument, he talked about similar results occurring with Australopoithecus afarensis (in other words, an Ape).  Macroevolutionists wanted to believe this to be the "missing link" between men and apes, but the fossil indicated that is was purely an ape.

Basically, judging by the outcome of these two discoveries (and many more), if macroevolution really did happen, then the fossil world would be littered with "missing links" which are transitional form fossils.  Macroevolutoinists have little evidence going for their beliefs, and a lot of evidence going against it, and not even their little evidence (such as the archaeopteryx and the 'ape') is fully accurate.  

With all these facts taken into consideration, it just goes to show you how absurd evolution can be, having little in-accurate proof supporting it, and a lot of accurate proof apposing it.  Through these studies, I've concluded how amazing our God is, in that he is able to create such distinct and different species.
   
Source: Dr. Jay L. While from Exploring Creation with Biology 2nd Edition

Supplemental Website

The following is a great place to spend more time in study regarding Chapter 9:  Evolution: Part Theory, Part Unconfirmed Hypothesis.



Sunday, January 25, 2009

Punnett squares

What is a Punnett square?  That is what we had to figure out in our last two labs.  In my last post I talked about alleles and how they affect genetic traits.  Well it turns out that alleles are represented or written as capital and lowercase letters.  For example, if a trait determined whether a plant was tall or short, we could call that trait H for height.  If the allele was dominant we would write it as H, if it was recessive we would write it as h.  

The two alleles put together determine a trait's genotype.  For example: If the trait for a plant being tall was dominant it would be represented as H,  that means that the short gene is recessive or h.  That means that if a plant was short it's genotype would be hh, remember that both alleles have to be recessive for the organism to have the recessive trait.  If the plant was tall it's genotype would be either HH or Hh.
  Remember that if only one of the alleles is dominant the organism has the dominant trait.

So what does this have to do with punnett squares?  Well, a punnett square is a way that we can use two organism's genotypes to determine the chances their offspring will have certain traits.  The way this works is by creating a punnett square.  This is what a blank punnett square looks like.

it looks like... a square.  but it is really very helpful.  So, in our example let's say a tall plant "Hh" breed's with a short plant "hh".  We put those genotypes on the sides of the square like so.

After that we just cross the alleles and fill in the blanks.

From this we can determine that 50% of the offspring would be tall "Hh" and 50% would be short "hh".  This does not mean that exactly half of the offspring will be tall and the other half will be short.  This only shows that there is a 50% chance of the offspring being tall.  Just like if you were to flip a quarter twice you would not necessarily get one head and one tail, it's the same thing with this.  Hopefully I explained punnett squares well and did not bore you to death.

Monday, January 19, 2009

Earlobes

Yes, earlobes. In our recent lab we had to construct an earlobe pedigree showing whether members of our family have attached (B) or detached (A) earlobes. It is supposed to help us learn about how traits are passed from one generation to the next. Our pedigree is shown on the right.
During this lab we learned about how genetic traits are passed from one generation to another. Every trait is represented by two alleles, which are the sequences of DNA that show whether a person has that trait. One allele is contributed by each of your parents. Alleles can either be dominant or recessive. If both of the alleles are dominant or only one is dominant then that person has the dominant trait, in our example this would be unattached earlobes. However, both alleles would have to be recessive to have the recessive trait, in our example attached earlobes (like mine).