Survival of the Sickest Chapter 6 Summary

Survival of the Sickest

Chapter 6

READING ASSESSMENT

This chapter of Survival of the Sickest begins by talking about Edward Jenner who was the first person to successfully discover a vaccine for a dangerous disease. The chapter then continues to discuss how humans are initially formed with only one cell, which is the product of a sperm cell and an egg cell. The chromosomes within the cells carry the instructions on how to build us. 

The chapter then explains how only 3% of DNA actually carries instructions on how to build us, while the other 97% does not do anything. Scientists originally assumed this DNA was "junk" and ignored it completely until the past couple of decades. Scientists then discovered that this " junk" DNA actually carried jumping genes and was related to viruses. These viruses turned out to be retroviruses. It was then believed that jumping genes actually descended from retroviruses and that are genomes have been modified by one particular retrovirus that made it easier for us to infected by other retroviruses. Therefore,  this "junk" DNA actually provided us with the code for our evolution from our primate ancestors. 

The chapter also talked about mutations within genes. The potential for evolution initially occurs when a mutation happens during the reproductive process of an organism. The effects of mutations are usually negative to the organism; however, they can prove to be beneficial. By studying mutations, scientists also discovered that instead of having 100,000+ genes, we actually have around 25,000 genes that serve multiple purposes and can be reshuffled with other genes.

The chapter also debunked rumors about inherited acquired traits and further explained jumping genes, which I talked about earlier in the summary. The chapter also discussed the genome's ability to gamble on mutation when survival situations became drastic. By gambling on mutation, the genome could end up creating a much stronger and better adapted organism that could possibly survive instead of die. There was also discussion of the development of antibodies and how once they are acquired they remain with the body and help to fight off future diseases.

This was a very interesting and complex chapter of Survival of the Sickest. The main focus of the chapter was genes and their different functions within an organism. 

"From Atoms to Traits" Blog

"From Atoms to Traits" Reflection

Significance of Mendel

Mendel was an Austrian monk who, through breeding different pea plants, managed to clarify the confusion about blending inheritance. His experiments proved that although different morphological differences occurred among the different pea plants, these traits were not entirely gone because they could reappear in later generations. He also noticed that offspring of the different plants usually resembled one of the parents in particular. Mendel's experiments ultimately altered the previous perception of how heritable variants occurred.

Drawing of DNA and Who Discovered It

Watson and Crick DNA Model 

as Drawn by Adam John Holliday

Five Examples of DNA Variation

Point Mutation- A single base-pair change occurs. This mutation inactivates the gene for signaling a molecule that regulates muscle growth.

Insertion- An intruding DNA element disables a gene that is necessary for starch synthesis. The water and sugar levels of the organism are thus altered.

Gene Copy Number- Entire cells are capable of being wrongly duplicated during cell division, which leads to differences between species that result in variation.

Duplication- Homopolymers within sequences are highly prone to duplication errors. These homopolymers being copied can lead to different coloration among organisms.

Regulatory Changes- Mutations in the DNA that control when and where genes are activated can lead to major deformations of an organism.

Evo-Devo

Evo-Devo is a biological field that analyzes the differences in the developmental processes of organisms in order to show the ancestral relationships between them.

Connection between Lactose Intolerance and Human Migration

The ability to digest milk after infancy was an unnecessary trait that hunter-gatherers didn't need to have thousands of years ago. The ability to digest in milk would have been an uncommon and abnormal trait that very few individuals would have possessed. Therefore, as the small population that had this abnormal trait would eventually migrate to different areas and pass this trait onto future generations. For this reason, the populations that were related to these "unusual" ancestors will be lactose tolerant while other population will generally be lactose intolerant.

Honors Bio Blog 16/69 (Does Race Exist)

I very foolishly typed this up and printed it the night before...
Here it is on my blog...

Does Race Exist?

The reading that I did last night presented some very interesting and persuasive arguments. The primary argument that was in the document was that humans are not necessarily divided into the "races"that we previously assumed. In fact, both our divisions and whom we are more closely related to are extremely different than what we had previously thought. For example, the main indicators that humans currently use to determine which race they and others belong to are usually the skin colors and facial features of a person. These assumptions of race based off of these two minor codes in our genes prove to be extremely inaccurate indicators. 

If we hope to acheive an accurate understanding of whom we are more closely related to and which "race" we truly belong to we will have to dive deep into our genetics. Researchers often use small strands of DNA known as Alus, which are extremely unusual because they serve no purpose but to randomly copy themselves into human DNA in random places. The Alus can be used to identify how closely related humans are to one another. Essentially, although on the surface it may appear that two people look very similar and therefore must be the same "race", they can actually be more unrelated than two people who look extremely similar to each other. Human beings incorrectly define "races" based off of different visisble physical characteristics; however, when humans are examined at a much more microscopic level the lines between different "races" become blurred. That's right! We are talking about blurred lines!

Progress of Own Self Learning and Self Analysis

Standard 9/1

Progress of Own Learning/Self Analysis

It's been a wild ride full of ups and downs this first quarter. I can't say truthfully that I am entirely satisfied with how I have performed in the class thus far; and I feel as though I can improve in several areas.

Organization- I really need to start keeping a more organized binder in order to ensure that I don't lose important data and let me team down like I have done in the past with the Brine Shrimp Lab. My organizational skills must improve if I wish to reach the level of success I want in this class...

My Blogs- I need to keep more up to date on my blogs. I often find myself falling three or four blogs at a time and then desperately struggling to make up ground at the last minute. Keeping up to date on my blogs will require me to become much more proactive and responsible for adding my blogs immediately after each class...

Attention in Class- I often find myself becoming distracted in class and this sometimes reflects on my performance on tests and quizzes. I need to learn to stay on task at all times and not be distracted my friends, daydreams, or any other things that will take my attention away from the class...

Overall Strengths- I performed very well on the first test and thoroughly grasped the concepts of diffusion and osmosis. I also rocked the House Case and completely understand how to write the Cases which will help me in the future class. I also have a strong grasp of modern evolutionary theory and feel as though I have kept up to date on the information learned in class...

Overall Weaknesses- I struggled with the Hardy Weinberg calculations and need to learn how to do these calculations if I wish to fully grasp all of the concepts we have studied so far. Other than calculations, I feel as though I have a strong grasp on the rest of the material, but need to learn how the standard based grading works...

All in all, I am optimistic and excited for what the future will hold!

Honors Bio Blog 12/69 (Evidence for Evolution Quiz)

Evolution Quiz Day

Today proved to be an extremely stressful day in Biology because I very stupidly left the binder containing my Brine Shrimp data at my house and was thus not able to present it in class...

After doing a brief review of the Brine Shrimp Lab, we proceeded to further discuss concepts about evolution and then prepared to take a very long quiz in a very short amount of time...

The quiz both covered some topics that we had previously discussed and introduced us to some new ones. All of the concepts covered on the quiz will be explained below...

Natural Selection- Natural selection occurs among organisms when some are more fit to survive than others. The organisms that survive are able to reproduce and thus pass their genes to the next generation; however, the weak species that die out our unable to do so and will naturally die off.

Survival of the Fittest- Survival of the fittest is a concept that goes hand in hand with natural selection. Essentially, the fittest organisms with traits that allow them to survive will live and reproduce, while those with undesirable traits will ultimately fail to reproduce and die off.

Fittest Organisms- The fittest organisms are the ones that are capable of reproducing and spreading their genes to the next generation. It doesn't really matter how long they live, the sole determinant factor of being demed the fittest organism is the amount of offspring that the organism is able to produce. The more offspring an organism produces, the higher chance that it has of spreading its genes and progressing the survival of its species.

Inheritable Traits vs. Non-Inheritable Traits- Traits that allow organisms to survive and reproduce are passed down from generation to generation. These traits could range from anything like fur color, shell composition, ear size, etc. and are passed down from the parents to their offspring. These inheritable traits are not to be confused with accidents that can befall organisms like broken legs, ruptured spleens, or sprained ankles. The consequences that these accidents have on organisms may shorten their lifespan and limit their ability to reproduce; however, they are not inheritable traits and will not be passed down to the next generation.


That is all for my blog today...
Please enjoy this very accurate depiction of evolution...

Honors Bio Blog 11/69 (Paleo Project)

1. Class 11

Today Mr. Quick was not able to make it to our class so we had a substitute teacher who was not nearly as cool as Mr. Quick...

The substitute teacher very cruelly gave us a quiz on controls, independent variables, and dependent variables. The quiz was fairly easy and had some questions that I found to be quite humorous. 

We were then given the rest of the class to work on our Paleo Projects. Bob and I decided that we would do our research on Platypi and began the long, arduous process of collecting data and finding the proper transitional fossil to write about.

All in all, today was a pretty easy class that provided the opportunity for us to get ahead on our projects if we so chose to...