the 1cm cube was most effective because it had less volume to diffuse with the pink dye. the factors effecting this are is the cube is small, its less space to fill, and less time to diffuse the whole cube
the cells cant grow very large because they need to transfer nutrients and feed organelles along with getting rid of waste, so if the cell is really big, they cant do the jobs efficiently
the 4:1 ratio cube will be more efficient because the surface area is larger in comparison to the volume.
for gas exchange your body, the ratio of a cell must be so that the cell membrane has enough surface area to serve the volume of the cell, including the exchange of gases
bacteria are single cell organisms, so they have to keep dividing in order to keep their surface area volume ratio adequate to survive.
multi cellular organisms don’t have to depend on just their organelles like bacteria have to they have specialized cells they can depend on.
the agar cubes 10 seconds after submersion into the base mixture. 10 minutes on the stop watch.
all the cubes after coming out of the 10 minutes submersion.
the most significant cube was the 3x3x3 cube, it was the most noticable diffused cube, once we cut into it, we saw how much hadnt been dyed.
Describe the process of translation: initiation, elongation, termination
initiation: the tRNA comes in with the anti codon pairing to the codon in the mRNA strand, which is held onto by a ribosome. each three letter codon is then attached with the corresponding anti-codon. the starting point is read by the P site, and the corresponding amino acid is then attached.
elongation: the amino acids are continuously added onto the mRNA, and a long chain of amino acids create a protein. the a site reads the next 3 letter chain, and then moves into the p site, and another tRNA is brought in.
termination: the mRNA codon then uses the stop codon to signal the tRNA to stop adding amino acids; there is no tRNA for the stop codon. the ribosome lets go of the mRNA, and then the tRNA lets go of the polypeptide.
2. How did today’s activity model translation? in what ways was it inaccurate?
it was accurate because we physically had to move the ribosome, and the tRNA from a site to p site. plus, we were also able to see a chain of amino acids forming, which is what creates proteins. the most inaccurate parts of the lab were the fact that the shapes of the amino acids and tRNA and mRNA were most likely not how the real things look.
DNA is made up of deoxyribose sugar but mRNA is made up of ribose sugar. DNA has thymine as one of the two pyrimidines while mRNA has uracil as its pyrimidines base.
describe the process of transcription
RNA polymerase binds to DNA at a specific sequence of nucleotides
Only one of the unmound DNA strands acts as a template for the RNA
RNA polymerase continues to elongate until it reaches the terminator, a specific sequence of nucleotides that signals the end of transcription
in what way was our model inaccurate? how did it do a good job?
the models we made were in accurate because they did not exactly show properly how transcription takes place with the unwinding mid way down he strand, but it did show the helicase and the polmerase which is accurate.
Name and describe the three steps in DNA replication. Why does the process occur differently on the leading and lagging strands?
1- the helicase unzips and unwinds the dna helix
2- the polmerase does complimentary base pairing for the lagging strand
3- the ligase moves and pairs nucleotides on the adjacent strand
the process is different on the lagging strand because the 5′ 3′ pattern is flipped and the ligase has to work backwards with rna primase
3. what did you do to show complimentary base pairing? how was this activity good/bad?
to show the base pairing on the adjacent strand and the regular strand, we used the corresponding beads from the leading strand to pair with the lagging strand. this activity was good because it showed the basic steps of replication, but it did not go into depth, which i believe would be more helpful.
Explain the structure of DNA – use the terms nucleotides, antiparallel strands, and complimentary base pairing.
DNA is a double helix structure, composed of backbones of sugars and phosphates. on one side, the sugars and phosphates are in a repeating pattern, and on the other backbone, they are anti-parallel reciprocating the opposite way. between the to backbones, there arenucleotides that make a ladder-like form, and the nucleotides pair up using complimentary base pairing here A-T, and C-G. A – adenine. T – thymine. C – cytosine. G –
How does this activity help model the structure of DNA? What changes could we make to improve the accuracy of this model? Be detailed and constructive.
This activity is very helpful in showing the twisted helix shape of the DNA strands, and putting the nucleotides on ourselves onto the strands was cool. I think that if there were beads to show the sugars and the phosphates would be better because here on our strand we only see the phosphates, and we can’t truly see the anti parallel patterns of the backbones. for example we could use red beads as the sugars so they contrast with the black phosphate beads. it would more accurately show the antiparallel structure.
the dna strand fully coiled into a double helix shape
Since we are depleting the natural resources of Earth already, we’re bound to run out of fossil fuels within the next 100 years. Yet if we start using nuclear energy, the waste byproducts of all this radioactive energy must go somewhere, so might as well dump it in a lake somewhere. Either way it sounds like we’re all screwed, but if I were to choose an ideal situation, I’d choose the nuclear energy. I would choose this because its cleaner, lasts longer, the plants would last longer, and it means that it would save the planet and its small amount of natural beauty I has left. Even though nuclear power has a costly down side, the benefits and positive side effects outnumbers those specific disadvantages. Sure, fossil fuels won’t cause a nuclear meltdown, and mass radioactive waste polluting our planet, but we at least need to consider it as a viable back up, because when not if, but when we run out of natural resources, have scraped the earth to its bare minimum, and the earth beneath us is crumbling because of thousands of holes drilled into the earth for oil and coal, were going to regret the way we treated earth. If radioactive waste is the positive outcome we must look forward to, in order to save our planet, then so be it. Humans started using fossil fuels just over 200 years ago, and we have used almost all of them. It took almost 600 million years to create the abundant sources we had and now look where we are. Nuclear energy has no greenhouse gas emission, so it saves the atmosphere from further damage, and it has up to 90% capacity factor. As well as being literally (in some cases), and figuratively “green” nuclear energy has no Sulphur dioxide or chemical pollution. Fossil fuels have polluted the earth for far too long where it’s getting to the point of no return.
When it comes to cons of nuclear energy most of them aren’t any concern at the moment. “But the power plant could explode or have an accident like Chernobyl!!” well, Chernobyl was a fantastic way to figure out how to get the most efficient and safe power plant, and the accident at Chernobyl isn’t very good to compare to now because there has been so many advancements in technology. If it was a power system failure during a test run, that means it was an operators fault, as well as their system wasn’t very good in the first place. Nowadays, nuclear energy plants can last up to 40 years, and if kept in perfect condition, no accidents, no failures, no mishaps; they can last another 20 years. We’re looking at up to 60 years per plants, that already had a 90% capacity factor, and that’s 60% less air pollution. The only “pollution” that these power plants give off are miniscule chemical particle pollution. And that is even 40% less damaging that the intense grey, or black smoke that oil or coal plants emit. Im just saying, that if we were to really, I mean really look at the comparisons and differences, the nuclear plants have more positives than negatives, and if we really want to save our planet from absolute ravaging in the next 100 years, we need to seriously consider nuclear power.
When the light beam hits the water stream, the laser light gets reflected inside the stream. Remember the surface of water is reflective both on its surface and below the surface. When light leaves a denser material, it will change directions. However when the critical angle is reached it will reflect back. Critical angle is the smallest angle of incidence for which light is totally reflected. Total internal reflection happens when a wave strikes a medium boundary at an angle larger than a critical angle, with respect to the normal to the surface. Critical angle of water is 48.8 degrees. When the angle of the beam crosses the critical angle the light does not go out of the stream and total internal reflection takes place. the water is a denser medium than air, and when the laser light is shone into the water, the light then creates total internal reflection. when the water picks up speed and flows out of the hole in the water bottle, and the light stays trapped in the stream. the beam of light then reflects on the under and top sides of the water stream.
constructive interference: when a wave is created on two sides of a medium, and then once it meets in the middle the wave becomes double the size of the two that met. they pass through each other, and then reduce down to their original sizes.
destructive interference: when two waves pass through each other but one is a trough and one is a crest, and once they meet, the briefly become flat in one spot. then they pass through each other and continue down the medium.
standing wave: a standing wave is when a medium is destructive but progressively gets faster and smaller, creating still spots called “nodes”. ours has 4 nodes which you can briefly see in the last few seconds of the video. this is also where the peaks do not move spatially.
The Trebuchet was invented in ancient China originally in the 4th century, and some documents were made of it in 1324, which the french engineer Renaud Beffeyte built his modern version from in 1984.
Who originally made the trebuchet?
Thought there are no documents of who exactly made the trebuchet, it is only recorded that ancient Chinese built the first working trebuchet.
When was the trebuchet invented?
There are different variations of when exactly it was invented, but 4th century china, and the 1300’s was when the trebuchet became popular.
Why was the trebuchet invented?
The trebuchet was built with the intention of throwing projectiles in sieges and battle, dating back to the battles in china. warfare was greatly enhanced by the trebuchet because it made a stepping stone for more advanced technology in warfare.
What were the short and long term implications of the trebuchet?
Short term implications would be destruction and more battle, sieges, and wars becoming more agressive. But in the long term, the trebuchet was a very successful invention that greatly increased designs for more advanced warfare technology.
The physics behind it:
this diagram sums up the physic behind the trebuchet, but to elaborate, it runs on kinematics, and different energies. when loaded and at rest, the machine has potential energy that sits in the sling, with the load, and when flung, or released, the kinetic energy is pulled into play, replacing the potential. Once released, the load, or ball, in this instance is forced through the air by the acceleration of the bar that hold the sling in place, and the load then reaches a constant velocity. the velocity is based on how fast it is released, which depends on the mass of the counter weight, the box opposite the sling. the counterweight pulls the bar down on one end, which then creates a chain reaction of: Counterweight released, bar pulled down, sling is flung up, load is released from sling into constant velocity, and finally the load coming with impact on its target (hopefully). The trebuchet also contributes to Newton’s Third Law of Motion which is as follows: “For every action there is an equal and opposite reaction”. in this, case, the end of the bar with the counterweight pulls that end down, which pushes the opposite end that equal amount upwards with the load, accelerating the load at that equal force into the air.
So if we were to use formulas and equations, a possible way to do so would be to find the that the trebuchet does, (½ ⋅ m ⋅ v²) would find the kinetic energy. of course you would need to do some runs to see what it velocity is, or you could use the initial velocity which should be 0 m/s.
Day by day process:
On the first day, Sarah and I discussed which invention we wanted to build, and we ended up deciding on a trebuchet.
On day 2 we came to class with our materials, and figured out how we were going to lay out our base so it could be the most stable.
day 3 consisted of continuation of the building process of the trebuchet. Sarah got burnt on this day from hot glue.
Day 4 was mostly building and last minute touches, with some trial runs to see if it worked. it did, and we were very happy about this, as we weren’t sure if it was going to work properly, but it did.
the last day of building, we were done with alterations and test runs, so we decided to take it outside and spray paint it. after that we did one more test, and it was complete!