EL's+Logbook+Week+of+Nov+12


 * 11/12~13/07**
 * ===Information=== ||
 * ===What I did & Opinion=== ||
 * 1. I had been sick for 2 days (even I took the school days off ), so I just took a rest at home. ||
 * ===What I did & Opinion=== ||
 * 1. I had been sick for 2 days (even I took the school days off ), so I just took a rest at home. ||
 * 1. I had been sick for 2 days (even I took the school days off ), so I just took a rest at home. ||

Repair shops for broken DNA
 * 11/14/07**
 * ===Information=== ||
 * http://science.nasa.gov/headlines/y2007/07nov_repairshops.htm?list62265
 * http://science.nasa.gov/headlines/y2007/07nov_repairshops.htm?list62265

- Point of this article "Fortunately, cells have teams of repair enzymes that try to fix this damage. Scientists have long thought that these enzymes always go to the site of injury and fix the DNA damage in place. But [|new research] by Francis Cucinotta, the Chief Scientist for NASA's Space Radiation Program at the Johnson Space Center, and his colleagues suggests that cells might sometimes move broken DNA to special "repair shops" instead."
 * Before this innovative research, Scienctists believe that there is a specific enzyme that repairs damange DNA on the spot. And actually the role of the

enzymes contributes to find the cause of various disease such as cancer. If most damaged DNAs are relocated after having fixed on a special zone, it will significantly affect other project related to the DNA. (Relocating DNA is a new concept in DNA research.)


 * Right:** DNA repair sites mapped by Costes //et al// at the NASA Space Radiation Lab. ||
 * ===What I did & Opinion=== ||
 * 1.Read the article about new discovery on the new approach to DNA repairing
 * 1.Read the article about new discovery on the new approach to DNA repairing

2. What is the significance of this discovery?
 * Due to this innovative discovery, now people can find a new way to treat noncurable disease and to analysis DNA.

It will greatly help to dig our body in more deeply. ( Not only the biology field but also the chemistry field will be aimed by this discovery. Biology cannot exist without chemical actions. ) ||


 * 11/16/07**
 * ===Information=== ||
 * [[image:http://www.biology.arizona.edu/cell_bio/pictures/1.gif width="200" height="151" align="left" link="http://www.biology.arizona.edu/cell_bio/tutorials/cells/cells.html"]]
 * Cell Membranes** Learn that membranes are fluid, with components that move, change, and perform vital physiological roles as they allow cells to communicate with each other and their environment.
 * Cell Membranes** Learn that membranes are fluid, with components that move, change, and perform vital physiological roles as they allow cells to communicate with each other and their environment.


 * Cell Signaling** Learn that living organisms constantly receive and interpret signals from their environment. Cells of multi-cellular organisms also receive signals from other cells, including signals for cell division and differentiation.
 * Studying Cells** Introduce yourself to the cell as the fundamental unit of life and the scientific method.
 * The Cell Cycle & Mitosis** Understand the events that occur in the cell cycle and the process of mitosis that divides the duplicated genetic material creating two identical daughter cells.
 * Meiosis** Understand the events that occur in process of meiosis that takes place to produce our gametes.
 * Prokaryotes, Eukaryotes, & Viruses** Learn about the cells that make up all living systems, their organelles, and the differences between living cells and viruses.
 * The Cytoskeleton** Learn that the cytoskeleton acts both a muscle and a skeleton, and is responsible for cell movement, cytokinesis, and the organization of the organelles within the cell.

=The Cell Cycle*= During development from stem to fully differentiated, cells in the body alternately divide (mitosis) and "appear" to be resting (interphase). This sequence of activities exhibited by cells is called the cell cycle. Interphase, which appears to the eye to be a resting stage between cell divisions, is actually a period of diverse activities. Those interphase activities are indispensible in making the next mitosis possible. //To see the animation for the cell cycle, click// [|//http://www.cellsalive.com/cell_cycle.htm//]

Interphase: Interphase generally lasts at least 12 to 24 hours in mammalian tissue. During this period, the cell is constantly synthesizing RNA, producing protein and growing in size. By studying molecular events in cells, scientists have determined that interphase can be divided into 4 steps: Gap 0 (G0), Gap 1 (G1), S (synthesis) phase, Gap 2 (G2).

Gap 0(00): There are times when a cell will leave the cycle and quit dividing. This may be a temporary resting period or more permanent. An example of the latter is a cell that has reached an end stage of development and will no longer divide (e.g. neuron).

Gap 1(01): Cells increase in size in Gap 1, produce RNA and synthesize protein. An important cell cycle control mechanism activated during this period (G1 Checkpoint) ensures that everything is ready for DNA synthesis. (Click on the Checkpoints animation, above.)

S Phase: To produce two similar daughter cells, the complete DNA instructions in the cell must be duplicated. DNA replication occurs during this S (synthesis) phase.

Gap 2(02): During the gap between DNA synthesis and mitosis, the cell will continue to grow and produce new proteins. At the end of this gap is another control checkpoint (G2 Checkpoint) to determine if the cell can now proceed to enter M (mitosis) and divide.

Mitosis or Phase: Cell growth and protein production stop at this stage in the cell cycle. All of the cell's energy is focused on the complex and orderly division into two similar daughter cells. Mitosis is much shorter than interphase, lasting perhaps only one to two hours. As in both G1 and G2, there is a Checkpoint in the middle of mitosis (Metaphase Checkpoint) that ensures the cell is ready to complete cell division. Actual stages of mitosis can be viewed at Animal Cell Mitosis.

> Viruses can reproduce only within a host cell > Phages reproduce using lytic or lysogenic cycles > Animal viruses are diverse in their modes of infection and of replication > Plant viruses are serious agricultural pests > Viroids and prions are infectious agents even simpler than virusesViruses may have evolved from other mobile genetic elements -The short generation span of bacteria facilitates their evolutionary adaptation to changing environmentsGenetic recombination produces new bacterial strains (Transformation, Transduction and Conjugation)Conjugation and Recombination in Bacteria. (Hfr and F-) Transposons The control of gene expression enables individual bacteria to adjust their metabolism to environmental change Operons, operators, repressors and inducers.
 * The genetics of virus and bacteria#[[image:http://www.iusd.k12.ca.us/uhs/apbiology/images/prion-grafik.jpg width="128" height="135" align="left"]]Researchers discovered viruses by studying a plant disease.# A virus is a genome enclosed in a protective coat.

http://www.iusd.k12.ca.us/uhs/apbiology/Unit%20Resources/Unit%206/unit6.htm || Based on my knowledge, there would be a malfunction of duplicating DNA but quiet not sure. (G2 Checkpoint is to function to copy the DNAs)
 * ===What I did & Opinion=== ||
 * 1. What will happen if the G2 checkpoint is blocked by any obstacles?
 * ===What I did & Opinion=== ||
 * 1. What will happen if the G2 checkpoint is blocked by any obstacles?
 * 1. What will happen if the G2 checkpoint is blocked by any obstacles?

2. Check this out! http://www.cellsalive.com/howbig.htm This link will lead to magnify the micro size of objects such as bacteria by comparing other cells. It is really really cool :D There are pin nail; human hair; dust mite; ragweed pollen; lymphocite; red blood cell; baker's yeast; E, coli; staphylococcus; Ebola virus; rhinovirus (+ Baker's yeast fermenting a bread or dough is even smaller that red blood cells !) ||