Inside of the nucleus are numerous chromosomes, which would be represented as the black pipe cleaners, the yellow ball is the centromere that holds the two chromosomes together: forming sister chromatids(the two small pieces of pipe cleaner). The sisters are identical, in that they have the exact genes. Each chromosome had a DNA double helix. Which is discussed below.
The picture above shows a structure of a DNA double helix, which is two stranded molecule full of nucleotides. Each side of the DNA, nucleotide, is made up of 3 units: phosphate, pentose sugar, and a nitrogen-containing base. Notice in the picture the red and white balls represent the sides of the ladder, which are composed of phosphate and sugar. The hydrogen consists of 4 different bases: Adenine(A), Guanine (G), Thymine(T), and Cytosine (C). Again notice in the picture that the steps to the ladder are composed of the bases just mentioned. Orange(A), Yellow(T), Green(G), and Blue(C). In between each ball is a small piece of black pipe cleaner (which represents the hydrogen bond). If this ladder were twisted the following pairs would occur: A-T, G-C.
During DNA replication: one side of the ladder remains as it is, while the other is away being formed as a new strand. Just remove one side of the ladder, the other side is getting ready to begin a new replica. The final DNA molecule consists of the original and new strand.
During transcription, a strand of mRNA, per the book, forms that is "complimentary to a portion of DNA." If you were to take a picture, as noted above, the two strands are a copy of each other. While clicking the camera, the strand of mRNA sneaks in and develops into a complementary base joined with the DNA bases. Although the DNA is a double strand and mRNA is a single strand. On the other hands, translation refers to the information in a different code. The green beads represent an enlarged ribosome, where tRNA molecules carry amino acids to the site during translation. During this process, polypeptide(black pipe cleaner) synthesis occurs. The messengers bind to the ribosomes, forming an anticodon(3 complementary bases).The process of Mitosis:
Picture 1 :
Picture 3:
Picture 4:
Picture 1: The beginning phase of Prophase: At this point there is no nucleolus, and the cell is in the process to divide. The yellow balls(centromeres) are starting to move towards opposite sides of the cell. The black pipe cleaners are the chromosomes (sister chromatids) the pink yarn are spindle fibers.
Picture 2: Metaphase: The chromosomes are lined up at the equator of the cell, and the spindle fibers have attached to the centromere.
Picture 3: Anaphase: The centromeres split from the sister chromatids(forming daughter chromosomes), and push away to opposite ends of the spindle. This process enables that each cell will receive the same gene.
Picture 4: Telophase: The chromsomes eventually end up at opposite sides of the cell. The spindles begin to disappear. The nucleolus appears, and there are two cells at opposite ends with DNA.
In conclusion, this model has helped me better understand different parts/functions inside of the cell. Although, with the compendium review having to explain different parts and processes, I feel like I was repetative, or may not have included some parts since I discussed them prior. DNA is a very in depth concept to learn. It may seem easy to say its purpose is to pass on genetic information, but that doesn't seem to justify all the work it actually does. All of the living parts inside of the cell work to together to complete their daily chores. Similar to the daily process of learning.
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