Fareeha Khan

Seminar C 2

LLOG 3 – Immortal Genes: Running in Place for Eons

            The existence of genes has been around since before humans even discovered them. This fact makes it particularly difficult for scientists who have been putting their efforts into tracing evolution because as their existence went unacknowledged in a time before advanced technology and organized science they were undocumented. However, not all hope is lost, for there are still clues all over the planet that help us piece together the components that make up evolution. In 1966, Tom Brock, a microbiologist, and his student Hudson Freeze collected samples of microbes in Mushroom Spring near the Lower Geyser Basin. By doing this they were able to find a bacterium that thrived in the 163 degrees F weather. They classified it as a “Thermus aquaticus.” In 1967 Brock collected more samples of microbes at the Yellowstone springs. Here he discovered organisms that could survive in 200 degrees F temperature. They literally lived in boiling water. Thus, a new study originated from these findings: the study of hyperthermophiles Some of the first species that inspired the study were Sulfolobus and Thermoplasma. They are lovers of heat. Brock classified these species into the bacteria clan. Brock’s next discovery that furthered the study was that of the Thermus aquaticus, a heat-stable enzyme that copies DNA even in extremely high temperatures. This brought the study to a level of multi million dollar standard in the diagnostics and forensics field. The third discovery was that of archaean genomes which have been vital in the study of evolution. These creatures have given us important clues that have helped us learn about our eukaryotic ancestors. The study catapulted the human race into a much deeper understanding of the earth’s past.

It is important for us to understand DNA because it enables us to comprehend evolution at a higher level. The way DNA works is very structured and systematic. Proteins are the most important part of DNA. They do things such as carry oxygen, build tissue, and aid in making copies of the DNA itself. DNA is held together by chemical bonds that follow a certain sequence every time. Proteins are made up of amino acids which are encoded with the bases that decide the sequence for the DNA. A gene is the length of DNA that is the code from the protein. There is a genetic code that biologists have found that is the same in every strand of DNA. This code in each DNA is transcribed onto a messenger RNA, which then becomes the amino acids that make the proteins. DNA are long strands of genes and sometimes the genes consist of codes that don’t mean anything and simply just exist for no reason. The genes and proteins are sorted into categories according to their function and similarity with preexisting genes and proteins. After scientists cracked the DNA code and studied the structure of DNA as a whole, we could begin to study our ancestors: eukaryotes and bacteria.

Eukaryotes are considered immortal because they have lasted over 2 billion years. They don’t avoid mutation; they are called immortal because the gene as a unit has endured so much over time. Amino acids are also considered immortal since they have been maintained throughout evolution. This is a vital power that natural selection holds: the ability to preserve information into genomes for eternity.

In order to understand and classify all living and non living things in the world, a system of kingdoms has been established. They began with the plant and animal kingdoms and then in 1866 Ernst Haeckel added a third kingdom of bacteria. However this third kingdom was not even acknowledged as the third kingdom until the start of the twentieth century. In 1938 Edouard Chatton named the species in this kingdom “prokaryotes” and “eukaryotes” to clarify between those with nuclei and those without it. Everything known in the living world can be classified under those two names. These species trees have been built upon their genetic kinship. This system definitely helped the study of the specs that were our ancestors. For example, scientists were able to theorize that because of the distinct similarities between archaea and eukaryotes that eukaryotes may have come from archaea. It has been discovered that eukaryotes came from archaean and bacterial parents. In 1970 Lynn Margulis’ research suggested that mitochondria and chloroplasts came from the bacteria that lives in eukaryote cells. These were important discoveries as it has led us into the direction of understanding how humans came about.

Take Away Idea

            The idea that we came from bacteria that is impossible to see without a microscope is incredibly intriguing. It just reiterates how amazing the development of science and technology has come to be. It is a part of life that must continue to flourish and be supported in order for humans to survive. The idea that I have taken away from this chapter is that all living species began from the same starting point. This is an important idea and one that is difficult to understand at times but it is an idea I will continue to study as we learn about evolution.

 

 

 

Most Challenging Concepts

            One concept that has just been hard for me to wrap my head around has been the idea that there are a plethora of sequences that exist on strands of DNA that don’t mean anything or do anything. Living in a fast paced world where time is precious and can not be wasted, it is just very confusing to find such amounts of “junk” existing in one of the most systematic formations on earth: DNA. As we learn how DNA has specific functions and orders that take place in every cell, I wonder if maybe the “junk” actually does have a reason for existing that just hasn’t been discovered yet.

A Seminar Question

Do you think there is a reason for so many unnecessary codes, a.k.a. “junk,” to be in existence on DNA strands which makes them longer and more confusing to understand?

Competency

            The detailed description of how DNA makes protein and the function of each component definitely helped my aesthetic awareness of the cell develop. This was littered with such specific commentary that it created a visual in my head where I felt like I was traveling through the cell as its functions were acted out. Also learning about all the effort that was put in by such scientists as Tom Brock, who created a whole new study that put humans so many steps ahead to understand evolution, really makes me appreciate all that science has uncovered about our lives. Despite my lack of skill in the field, it is a constantly revolutionary and revitalizing study of life that has helped increase our quality of living significantly.

            The advanced technology used to discover such tiny microbes that clued us in about our eukaryotic ancestors is such an intricate work of art. Our development of information technology has truly been the main factor as to why we have learned so much about evolution thus far. Appreciating this fact alone is something that should be done by all as we will continue to learn more facts that are being discovered by evolution Connection

As I finished reading this chapter I was overwhelmed by how it was jam-packed with so much information. I had learned so much in the time it took to read this. It reminded me of when I first began my fascination with outer space. I’ve had this fixation since I was a child and the vastness and openness of space has never ceased to amaze me. Space is such an interesting concept because it is so hard for humans to comprehend since there is nothing like it on this planet. Similar to the study of evolution, it is extremely difficult for people to understand this concept since it is still being developed as a theory and because there is so much that we don’t know about it. However, I have faith in this theory just as I do in the universe around us and as interest and technology heighten, so will a general understanding.

Vocabulary

Bacterium – single celled, parasitic microorganism that has no nuclei or organized cell structure

Thermophilic – species that thrive in hot water

Kinship – related through having characteristics in common; from the same origin

Key Concepts

  1. Since species have been discovered that can survive in boiling temperatures, to everyone’s surprise, then this can mean that there are many more species that live in conditions that we thought no one could live in.
  2. Genomes contain an extensive collection of history that is vital in helping us understand many different scientific concepts.
  3. All living things in the world can be classified under either “prokaryote” or “eukaryote.”