ELA Component
I have chosen to focus on mitosis for my Science PBL project. For my ELA connection, I will complete a journal (Option 1). I will present this journal by adding it as a document under my PBL website. The journal I will be presenting will include the following: 10 entries, my thoughts about my project, process of research, outcomes of the experiment, interaction with my peers, etc.
Jerosh Jacob
PBL Task 13
Journal Entries
Day 1: 11-8-13
Today I learned what mitosis is. Mitosis is the simple duplication of a cell and all of its parts. It duplicates its DNA and the two new cells (daughter cells) have the same pieces and genetic code. Two identical copies come from one original. Start with one; get two that are the same. Ask.com says, “Mitosis is defined as the division of cell in which a nucleus divides into nuclei in such a way that each contains equal number of chromosomes.” Some organisms reproduce asexually, and through Mitosis they make copies of themselves to grow in population. Bacteria will do this, which is why they can grow so quickly on some surfaces.
Day 2: 11-9-13
Today I did some research on mitosis and how it was discovered. I learned that Walther Flemming coined the term mitosis in the early 1800s deriving from the Greek word for thread. Walther Flemming was born on April 21, 1843 in Sachsenberg, Germany. Flemming's father, Carl Friedrich Flemming, was a psychiatrist. Flemming studied medicine at the University of Rostock in Germany, and later graduated in 1868. After finishing his studies, Flemming served in the military as a physician and later taught at the University of Prague. He was a pioneer of cytogenetics and he was the first person to conduct a systematic study of chromosomes during division and called this process mitosis. He saw that chromosomes were "doubled" when they appeared in prophase, and "solved" the problem of chromosomal partitioning between mother and daughter cells. This was significant for later work in meiosis and the chromosomal theory of inheritance.
Day 3: 11-14-13
Today I found out that Flemmings discovery of mitosis is considered one of the 100 most significant scientific developments of all time. It is also included on the list of the 10 most important discoveries in the field of cell biology. Much of what we know today about mitosis originated with Flemming's observations. He is known as the father of cytogenetics. In 1902, he retired as Privy Medical Officer because of a progressive disease. In his last years, he could no longer leave the house at Düsternbrooker Weg 55, which no longer exists, due to a femur fracture. He died of pneumonia on 4th August 1905 in Kiel, Germany.
Day 4: 11-15-13
There are two driving questions for this experiment. How do organisms grow and develop? How is the cell cycle regulated? The cell cycle, or cell-division cycle, is the series of events that take place in a cell leading to its division and duplication (replication). It is essential to know how organisms grow and develop because we grow and develop everyday too. Also the cell cycle goes on in every living organisms body, so it is important for us to know how it does what it does.
Day 5: 11-16-13
Materials I need for this project are a modeling mitosis kit, string (2 meters), and a tape. The optional materials to conduct this experiment are prepared microscope slides of onion root, planarian regeneration kit, and karyotypes of normal cells and cancerous cells. I think these materials are needed for us to answer questions dealing with cell reproduction under a microscope. There are many questions that can be asked dealing with mitosis. Where is DNA found within a cell? If the long string had to fit into a very small compartment, what would you do to the string to make it more compact? How does this relate to the organization of DNA within a cell? What is the difference between chromatin and chromosomes?
Day 6: 11-17-13
This project can be done by simulating different phases of mitosis. For instance, we can simulate the anaphase or telophase. This string represents the amount of DNA in a human cell if all of the DNA molecules were placed end-to-end in a straight line. we can use pop beads or pipe cleaners to represent chromosomes. Also, we can use tape or string to represent the cellular membrane and nuclear membrane. Also, we can make simulate phase using these items.
Day 7: 11-18-13
Today I discovered that all cells follow a similar pattern of development for at least part of their lifespans: cells first grow, then divide to produce two new cells. This is true of unicellular prokaryotic and eukaryotic organisms, and it is true of the cells that make up multicellular eukaryotic organisms. Cells grow by adding materials to their cell membranes and cell walls, if present. Cells divide either by fission, as in prokaryotic organisms, mitosis, or meiosis. The process of cell division is inherently intricate – cells must partition their DNA and cell contents appropriately into the new cells that result from division. In addition, organisms need to control when and how often cells divide in order to develop properly and ultimately to survive
Day 8: 11-19-13
The cell cycle contains 4 phases: G1, S, G2, and M. The main components of cell cycle regulation are CDKs (cyclin dependant kinases) and cyclins. CKDs remain at a constant number throughout the cycle whereas cyclins fluxuate. The two main checkpoints are G1-S and G2-M. If there is no DNA damage in G1, then there will be enough cyclins produced to bind to the CDKs which allows the cell to enter S phase (DNA replication). The G2-M checkpoint ensures there is no DNA damage, and also that the chromosomes have successfully replicated. If everything is in order, then the M phase cyclins will be abundant enough to bind to the CDKs. This allows the cell to enter into mitosis.
Day 9: 11-20-13
Today I learned that, when a normal cell goes through mitosis, there are various checkpoints where the cell makes sure it's healthy and ready to divide. Perhaps the most important ones relative to cancer are the DNA damage checkpoints. Any damage contrary to this control mechanism will make the cell to attempt correcting it and when it fails the cell destroys itself through a process known as apoptosis and the mutation is propagated to daughter cells. These to continue dividing into new cells thus resulting into cancer. The DNA should be checked before damage begins. Understanding the checkpoint pathways and genes involved in the cellular response to DNA damage and cell division events in normal and cancer cells, provides information about cancer predisposition, and suggests design of small molecules and other strategies for cancer therapy.
Day 10: 11-21-13
Interphase is the phase of the cell cycle in which the cell spends the majority of its time and performs the majority of its purposes including preparation for cell division. In preparation for cell division, it increases in size and makes a copy of its DNA, which is made during the S phase. Interphase is also considered to be the 'living' phase of the cell, in which the cell obtains nutrients, grows, reads its DNA, and conducts other "normal" cell function. The majority of eukaryotic cells spend most of their time in interphase. Interphase does not describe a cell that is merely resting but is rather an active preparation for cell division.
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