Unit 5 Reflection

Unit 5 Reflection

          In this unit, we learned about the different types and factors of mutations. Since mutations are something that really fascinate and intrigue me, I was able to keep up with this unit very well. The themes and essential understandings were mainly about the causes and effects of mutations and why the appropriate characteristics develop only in the appropriate organs at the appropriate time. Some of the causes of mutations can be by environmental factors such as UV rays from the sun, and most mutations either have a very small effect or no noticeable effect at all. Because of gene regulation, we have a control and or balance of characteristics where we need them. Understanding mutations and their effects were a part of my strengths during this unit and trying to understand gene regulation and the lac operon were my weaknesses. 

          I grew as a student during this unit by learning how not all mutations are deadly and cause diseases, but also understanding that most of the time that is the case. I also found it very interesting that gene regulation is the reason why we don't have four ears or six eyes. Overall, this unit, to me, was incredibly fascinating. Mutations are something I find grasping. 

Protein Synthesis Lab

Protein Synthesis Lab

           1.  There are 8 required steps when making a protein. During transcription, the first step occurs when a section of DNA, known as a gene, is copied by an enzyme. The copy that is produced is called messenger RNA or mRNA for short. RNA is different from DNA because uracil replaces thymine, and RNA is single stranded. The mRNA then leaves the nucleus and travels to the cytoplasm. The next step begins translation, where the mRNA bonds with a ribosome, which will make a protein. The ribosome reads the first three bases called a codon, and determines which amino acid corresponds with that sequence. Each amino acid that is added is determined by the codon read by the ribosome. Amino acids are bonded together, and when the mRNA is done being translated the amino acid chain folds up to become a protein. 

         

          2.  Throughout the several different types of mutations I tested, I concluded that deletion had the greatest effect on proteins and substitution had the least effect on proteins. No, it doesn't matter where the mutation occurs, since the amount of effect will still remain the same. The only way this would be different if the T was near the end is that it would change an amino acid.

"Types of Mutations." Types of Mutations. N.p., n.d. Web. 13 Dec. 2016.

          3.  I chose deletion because it has the greatest effect on proteins. This mutation had a greater effect because it deleted a letter in the sequence without replacing it with anything, therefore completely altering the amino acids in the sequence. It doesn't matter where the mutation occurs, since it will effect the protein greatly without needing a specific location. 

          4.  An example of a mutation that could affect your life is sickle cell anemia. Sickle cell anemia causes red blood cells to become deformed and form a sickle shape, which then clogs blood vessels, can slow or block blood flow throughout your body.

DNA Extraction Lab

DNA Extraction Lab

          In this lab, we asked the question, "Can DNA be extracted from cheek cells, and if so, at what point do you predict you will be able to see the DNA?" To answer this, I said yes, DNA can be extracted from cheek cells because our skin cells have our DNA in them. We found that we would be able to see the DNA after adding the detergent, salt, and pineapple juice to the gatorade mixture and after carefully placing alcohol on top of it. The DNA fell out of the solution as the alcohol was added because the alcohol is nonpolar and the DNA is polar. My hypothesis was "If DNA is in our skin cells, then we will be able to separate DNA from our cheek cells." 

        One of the errors we encountered in this lab was an issue with the lids falling inside of the test tube, rather than closing the test tube. Because of this, we weren't able to effectively shake the mixture we had created with the gatorade, salt, detergent, and pineapple juice. One recommendation I have for anyone conducting this experiment is to be sure to use a cap that fits the right test tube, otherwise, the experiment will most likely turn out wrong for that person. 

       The DNA extraction protocol involved three steps: homogenization, lysis, and precipitation. We used the gatorade to homogenize the cell tissue in our cheeks. We then added soap to lyse the cell membranes and to emulsify the lipids and proteins of the cell. This disrupts the polar interactions that hold the cell membrane together. We then added pineapple juice as a catabolic protease to further break down any proteins called histones that the DNA molecule wraps itself around. 95% isopropanol alcohol was then layered on top of the mixture. Since the alcohol is nonpolar and the DNA is polar, the DNA falls out of the solution as a precipitate right at the interface of the two solutions. The DNA can then be pulled up from the alcohol layer and then collected with a transfer pipette. This lab was important in understanding biological concepts by demonstrating what it means to homogenize a mixture, and what lysis and precipitation mean. 

        

       

Infographic

Egg Diffusion Lab

Egg Diffusion Lab

            The mass and circumference of the egg when the salt concentration increased got a lot smaller, with an average percentage change in mass of -46.0925% and an average percentage change in circumference of -22.11%. A hypertonic solution caused the change because there was more solvent in the egg that left to dilute the corn syrup, causing the shrinkage. The solute moves from areas of high concentration to low until they reach equilibrium.

        A cell's internal environment changes as it's external environment changes by using diffusion to adapt to different external environments in order to survive. When the egg was placed in vinegar, it got bigger because since vinegar is part water, it was able to diffuse the water into it to adapt to the new conditions of the vinegar. When placed in water, the egg returned to it's normal size because of an isotonic reaction with the water inside the egg and the water outside the egg. When the egg was placed in sugar, it shrunk because of the solute leaving the egg.

       This lab demonstrates hypotonic, hypertonic, and isotonic reactions within a cell. Since we are learning about diffusion and these reactions in class, this lab was important for our proper understanding of the subject.

        Fresh vegetables are sprinkled with water at markets so they can stay in a diffused state and remain healthy and fresh. Salting the vegetables would dehydrate them because of a hypertonic solution that would cause the water to diffuse and be replaced with salt water, causing the vegetables to dehydrate and shrivel.

       Based on this experiment, I would want to know why snails bubble when they get into contact with salt. I'd want to find a snail-friendly way of testing this though, of course. I think it happens because of a hypertonic reaction with the moisture on the snail's skin conflicting with the salt. 

Egg Cell Macromolecules Lab

                                                              Egg Macromolecules Lab

            In this lab we asked the question, "Can macromolecules be identified in an egg cell?" We found that proteins, monosaccharides, polysaccharides, and lipids were all found in the egg whites, while the other parts of the egg only had a few. Our hypothesis for the egg white was that if the cell walls include monosacchardies and polysaccharides, then these will also be found when testing the egg whites. There were about 5 of each macromolecule in the egg whites, and the colors observed were purple (monosaccharides), yellow-orange (polysaccharides), purple (proteins), and white-orange (lipids). Our hypothesis for the egg yolk was that if the egg yolk is a giant cell, then all of these macromolecules will be found in it. Every macromolecule was found in the egg yolk except for lipids. The quantitative and qualitative amount of macromolecules found were dark purple, 8 (monosaccharides), golden, 7 (polysaccharides), brown/purple, 8 (proteins). Our hypothesis for the egg membrane was that if the cell membrane is made up of lipids and proteins, then when testing the egg membrane, lipids and proteins will be found. Proteins and lipids were present in the egg membrane, with qualitative and quantitative observations of purple, 3 (proteins), pink/red, 2 (lipids). This data supports our claims that

         Our data contradicts the expected results because while we expected every macromolecule to be present in the egg yolk, it was missing one of them. There weren't any lipids present at all in the egg yolk and because of this, our hypothesis of "If the egg yolk is a giant cell, then all of these macromolecules will be found in it," was false. One error we came across is that for the polysaccharides test, the person testing accidentally put too much iodine in the egg white. Although we only had one error, another possible one could've been cross-contamination of the chemicals. Due to these errors, in future experiments, I would recommend carefully watching how much you put in each test tube and cleaning each dropper everytime you use it.

         This lab could have been improved by maybe keeping better track of our observations and communicating with each other more for more accurate results. This lab was important in understanding biological concepts because the egg is a very good representation of a cell, since it literally is just one giant cell. By interacting with an actual cell, we were able to grasp a better understanding. 

Unit 2 Reflection

       This unit was about the nature of matter, compounds, molecules, bonds, acids, bases, and pH. In response to the essential unit question, I believe that increasing molecular complexity serves as the building blocks for life by learning from the ground-up, starting with atoms, the basic unit of matter, and working your way up to compounds and molecules or the types of bonds. By learning these things in order, it gives us a better understanding of what we're really learning by starting small, instead of diving in head first.
        About the nature of matter, I learned that atoms are the basic unit of matter and make up everything we see and feel in this entire world, including all of us. Atoms are made up of three particles; protons, neutrons, and electrons. Protons have a positive charge and have the same mass as neutrons, neutrons have no charge/neutral charge, and electrons are negatively charged, and are 1/1840 size of a proton while always in constant motion. The nucleus is in the center of an atom, made up of protons and neutrons. I had no trouble remembering the charges of each of the particles, though I occasionally have trouble remembering what the nucleus is and what it's purpose is. Atoms are also the basic unit of elements, which are pure substances that are listed on the Periodic Table with their atomic number. The atomic number of an element never changes.
     I also learned that compounds and molecules are formed by two or more elements and have formulas, which are abbreviations of the number and types of atoms in a molecule (Ex: H20 = 2 hydrogens + 1 oxygen). I have trouble memorizing the different types of bonds, so I realize I have to work on that. Chemical bonds are the energy stored between atoms. There are three types of bonds; Ionic bonds, Covalent bonds, and Hydrogen bonds. Ionic bonds form when an atom gains or loses an electron, covalent bonds are electrons shared between atoms and could have double or triple bonds, and while hydrogen bonds are not as strong as covalent or ionic bonds, they are able to hold molecules together due to slight attraction of positive to negative charged regions. I had a lot of difficulty memorizing the types of bonds and their purposes, so I'm going to keep working on that.
      We learned why water is wet by first going over the properties of water. One of it's properties, polar is the unequal distribution of charge between H and O. It has the ability to form multiple H-bonds, is the most abundant molecule in most living organisms, is less dense when frozen, and has high specific heat - absorbs a great deal of energy.
     I learned that pH is the measurement of hydrogen ions in solutions. I was also taught about the pH scale, 7=neutral, anything larger than 7 is acidic, and anything less than 7 is basic. I might have trouble remembering the scale, so I'm going to study that some more.

Sweetness Lab

                                                                         Sweetness Lab

     1. I believe that monosaccharides are sweeter than the other forms of carbohydrates, since fructose and glucose are really sweet and are monosaccharides. Disaccharides are neutral, since while sucrose is really sweet, lactose and maltose really aren't. And finally, polysaccharides are the least sweet, since both starch and cellulose are really bland.

2. In crystalline form, most monosaccharides are present in a "long chain" structure. Some monosaccharides are modified by cellular enzymes to enhance or change their cellular function. The number and type of monosaccharides used, as well as the position of bond between them, determines the 3D structure of each carbohydrate.

3. All testers gave each sample the same or near the same rating. One reason why it could taste different for one person is if they have different tastebuds, accidentally mix sugars, or dont drink water between tasting.

4. Our tongues detect the majority of the tastes using protein receptors on the surface of the taste cells. The receptors snap together in specific ways, and when they do, the cells send signals to the brain reporting the molecules' presence. Therefore, the testers could rank sweetness differently because although our brains can recognize the same five tastes-bitter, sweet, salty, sour and savory-the suite of chemicals can trigger those signals vary from one person to the next.

Characteristics of Life

Jean Lab

In this lab, we asked the question "How would it affect the jean fabric squares if we put different amounts of bleach in each of the petri dishes they were in?" We found that 100% bleach affected the jeans the most, and, in order, 50%, 25%, 12.5%, and 0% were not quite as effective as 100% bleach, but still did a lot of damage. 100% bleach drained nearly all of the color in the jeans, their once dark blue navy color now a blue white. 50% bleach took away most of the color but still left it blue. 25% bleach affects the texture of the jeans, but not so much the color. And finally, 12.5% and 0% did little to no damage to the jeans. This lab was important for our learning because it taught us more about the scientific method and gave us a better understanding of it.