Category Archives: Grade 12

Diffusion In Agar Cubes

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  1. The 1cm x 1cm x 1cm cube was the one that had a diffusion percentage of 100% with our test  as it was the one cube that turned pink all the way through.
  2. it was the smallest size, so because there was less agar that the NaOH had to go through to produce the pink colour it was able to turn the entire cube pink within the amount of time. the important factors that affect how materials diffuse into cells and tissues are the size of the tissue or cell. Along with the size, the type of material, temperature, and concentration affect how materials diffuse into cells and tissue.
  3. The larger surface area allows the cell to diffuse better due to the fact that cell is in more contact with whatever material is being diffused into the cell, but if the cell grew then the volume would increase and the ratio of surface area to volume would decrease which would lower the effect of the diffusion as it would take much longer to get a percent diffusion of 100%.
  4. according to the data we recorded a higher surface area to volume ratio is more effective at maximizing diffusion, so because of that the 4:1 ratio would be the most effective. This means that the surface area is higher that the volume.
  5. To help exchange gases our body adapts the shape off the cells to make them have a decrease in volume and an increase in surface area. For example, our lungs expand so that we have take in oxygen and then let out carbon dioxide.
  6. Once surface area increases the volume will be small to maintain efficiency. So, if the size of cells increased it would no longer be efficient and diffusion could not happen throughout the entire cell.
  7. multicellular organisms which are animal and plant cells can have a larger surface area to volume ratio. They can have special features that include gas exchange, our lungs, and circulatory system, our blood. These features help and speed up the movement of materials into and out of an organism.

Protein Synthesis

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Transcription:

  • The difference between mRNA and DNA is that DNA is made up with Deoxyribose sugar and mRNA is made up of Ribose sugar. There is also a difference with the pyrimidines, DNA has a thymine pyrimidine and mRNA has a uracil as a pyrimidine base. DNA has 2 backbone strands, whereas mRNA has 1 backbone strand
  • There are 3 phases within transcription
    • the unzipping and unwinding of DNA which separates the two backbone strands, as seen in the photo the DNA is not in a double helix shape and is separating.
    • Complimentary base pairing with DNA backbone, as seen in the photo the strand of RNA is formed as nucleotides covalently bond together and build an RNA backbone. This process is caused by the RNA polymerase.
    • Separation from DNA, shown in the photo below we see how the RNA now separates from the DNA after copying the information from the DNA template strand. From here the double helix shape would reform with the DNA.
  • This modelling process did a good job in showing the transcription process to capture the big ideas, but one thing that the model lacked was showing how nucleotides form to build RNA not just RNA bonding to the DNA strand.

Translation:

  • Initiation
    • Ribosome holds a mRNA
    • The p-site reads the starting codon which is AUG, then the matching tRNA bring an amino acid
  • Elongation
    • The amino acid chain grows
    • The a-site reads the next codon on the mRNA strand and then brings the matching tRNA. From here the tRNA on the p-site transfers over to the tRNA on the a-site.
  • Termination
    • a stop codon will appear within the mRNA strand and there is no tRNA for a stop mRNA
    • The ribosome releases the mRNA.

 

  • The modelling process is accurate in showing the RNA and how the ribosome is holding it, also the overall tRNA building process it accurate, but one thing that is inaccurate is how the amino acid in the p-site and a-site match up with the codons.

DNA and Protein Synthesis

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  1. DNA stands for Deoxyribonucleic acid
  • The structure has 2 backbones that are made of sugar-phosphate units and the complimentary bases extend inward and hydrogen bond.

  • The backbone strands are antiparallel and the structure twists into a double helix shape which is the twisted shape you see below.

  • Sections of DNA are called Genes and each gene are instructions to build a protein
  • Each gene is about 1000 nucleotides long
  • The DNA strands are packed into chromosomes within the nucleus
  • Each chromosome is 1 DNA molecule which is 85,000,000 nucleotides long.

2. This activity helps with understanding the parts of the DNA molecules like the sugar-phosphate backbone and the complimentary bases. The sugar-phosphate backbone and where the phosphate goes was a good way to help understanding and also whether the bases were double or single ringed were good as well. To make it more accurate you would need more details of each part, for example showing the double helix shape better. In the photo below the blue strips with pink represent the sugar-phosphate backbone and the white pipe cleaners with the beads represent the bases and have either 1 or 2 beads depending on if the base is double or single ringed.

 

 

 

 

 

 

 

  • DNA replication occurs before cell division, the photo below shows the separation of  DNA that occurs within the nucleus and you can see the green triangle of play dough acting as the helicase to separate the DNA.

  • The DNA helicase first unzips the the DNA separating into two strands, from there the DNA polymerase pairs the complimentary bases together, and the DNA ligase joins together the nucleotides creating a new strand of DNA. The process for leading and lagging strands are different because the backbones of DNA are antiparallel. In our photo it shows the second backbone for a new DNA molecule is being created, in addition to the first photo you see the red block acting as the polymerase that connect the two strands together by the complimentary bases as well as the blue circles which represent ligase which join the nucleotides together.

 

  • For the complimentary bases we just twisted the white pipe cleaners that had the beads together which don’t really show the hydrogen bonds very accurately. Also for the adjacent nucleotides it was just a single blue pipe cleaner with the “phosphate” beads and did not show each nucleotide separately, which affects to visual representation for the function of ligase.n is a broad sense this was a good visual representation of how DNA is formed and the parts of DNA. It was also good to see the process of DNA replication, but it is not very effective in showing the functions for ligase and polymerase without explanation.

English 12 Poetry Project

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Image result for athletes being yelled at

                                               

                                        Following the System

By Jesse Lee

 

Bigger game, bigger place, bigger system.

Bigger is not always better.

More recognized is not always credible.

More teammates, more competitors, single player.

Good, but want to improve. Wasn’t taught. Was told.

The reason for one’s fall is how they rose.

Put in a system for many.

But many only followed a single standard.

Drained of purpose, drained of reasoning.

The hunger begins to starve.

The system is just a clock counting.

How long will you last? Can you last?

Now your last. Will you stay at the bottom?

With a broken base.

Or rebuild knowing that this was once your happy place.

Stay down knowing everything is corrupt.

But when at the bottom,

The only place to go is up.

 

Poem Inspiration:

 

Poem:

My Reflection/Discussion:

 

Poem Composition:

The poem I enjoyed most of the blood and roses poems was He Sits Down on the Floor of a School for the Retarded. This poem was one of the few that spoke about the roses side for things that are intangible, and everyone could relate to. Human connection is something we all have some sort of desire for and the poet depicted it so well through his imagery. He shows the human connection between two different people that don’t know each other and how meaningful this type of connection can be. He also shows how one needs to put aside all of the societal norms and the effects of other people’s views to be able to have a connection like this. This is so relevant in today’s world because everyone sees what people can do and socially connected through technology. What I get from this through a modern-day point of view is that no matter what other people think and how connected we are through technology; we will always have desire for intangible human connection, and this is something that every human no matter what type of person they are wants to feel. This poem definitely is about the roses side, but still acknowledges some of the blood within our world through societal norms and perspectives and we also see some of the main characters arrogance through him thinking that the most natural thing about humans which is affection is unnatural. This is most likely from the conformity from society and being accustomed to what society thinks.