9/6/13: Cell Membrane and Differential Diagnoses

 

          Today’s lesson was on cell membrane, function, structure, diffusion, and osmosis. I learned that there are 3 different types of facilitated diffusion: channel, carrier, and active transport diffusion. In all three types of diffusion the proteins help speed the process. I also learned that proteins have 6 different functions. Proteins transport with water and ATP, enzymes, passing on signals, recognize other cells, helps attach cells to other cells, and other things.

 

 

 

 In addition to the lesson, we began the House Case. We listed the symptoms, the needed tests to be done, and the differential diagnoses. We obtained more information from Mr. Quick which helped eliminate some possible diagnoses. At the end of class, we received some test results which will help us determine the correct diagnoses.

 

Diffusion Lab : 9/4/13

      In class 9/4/13, we did two labs. In part 1, we made a cell and filled it with a solution that had 15% glucose and 5% starch. We placed this cell in a cup and added water. Then we added iodine to the water and saw that inside of the cell that had the clear solution changed to a bluish black solution. This reaction occurred because of diffusion, the higher concentration iodine moved into the lower concentration solution inside the cell. Then there was a reaction between the iodine and the starch that occurred which resulted in the solution inside the cell to turn into a bluish black color.

 

 

      The second lab we did also tested diffusion. We had three pieces of agar cut into different shape that were sitting in potassium iodide. We measured the surface areas of each piece and place them into a beaker filled with water. Then we added iodine and waited three minutes. We found that the pieces had changed to a bluish color. We took the pieces out and cut them to see the insides. The insides were still white because we did not wait long enough for the diffusion process to complete.

 

 

 

Diffusion and Osmosis Labs: Part 2 and 3

In class 9/2/13, we did two labs. The first lab was Osmosis- Movement of Water High to Low. The objective of this lab was to find the molarities of the different solutions. In order to do so, we created six cells and filled each with 7 milliliters of different liquid substances in each cell. We massed each cell and then placed each cell into a cup filled with distilled water. We waited 30 minutes and re-massed them and calculated their percent change of their mass. We found that the blue liquid substance had the lowest Molarity because it was actually water. Through osmosis, the blue substance in the cell permeated through the cell because the blue substance had high concentration and permeated from the cell to get to the low concentration distilled water. On the other hand, the red liquid substance which had the highest Molarity increased in mass because the distilled water moved into the cell which contained lower concentration liquid.

 

 

In part 3, we cut a red potato into 24 pieces and massed 4 potatoes as a group. We placed each group of potatoes into a cup and added a different solution to each cup. Then we covered each cup with Parafilm. We came in 9 hour and re-massed the potatoes in each cup. Then calculated the percent change. We found that the result to be opposite from the previous experiment. The potatoes that were in the red solution had the lowest percent change and that the potatoes in the blue solution had the highest percent change. The potatoes in the blue solution(water) increased in mass because the potatoes absorbed the water since the potatoes has a low concentration. The potatoes in the red solution had the lowest percent change because both the potato and the solution had almost the same concentration.

 

Class 8/26/12: Basic Chemistry

 

    In class 8/26/13, we reviewed basic chemistry. We had to choose between two worksheets on covalent and ionic bonding or build molecular models. I chose the worksheets. The point of these two excersizes was to refresh our memories and review how molecules bonded.  On the worksheets, we had to draw Lewis dot structures, determine polarities, and count the number of protons, electrons, and valence electrons. The purpose of these exercises was to prepare us for biochemistry.

Properties of Water

       Seventy percent of the earth’s surface is water.  Sixty percent of the human body is made up of water. Water is the only molecule that can exist in all three states: solid, liquid, and gas. Also, water has a covalent bond and is polar because the unequal sharing of unequal sharing of electrons. The oxygen (8 protons) attracts electrons more strongly than hydrogen (1 proton).

            Water has four properties that facilitate environments for life: cohesive behavior, ability to moderate temperature, expansion upon freezing, and versatility as a solvent. Cohesion is the ability for water molecules to bond and adhesion is the ability for those molecules to stick to other objects. An example of water’s cohesive behavior is in trees. The water molecules first stick to each other through cohesion, and then the water molecules stick to the xylem (tubes inside trees to transfer water up). After adhesion the molecules move up the tree and go up to the leaves and evaporate through transpiration.



            One of the four properties of water is the ability of water to moderate temperature.  Water takes thirty times longer to heat up than gold because the water absorbs energy and releases energy through creating and breaking bonds. That characteristic explains how ocean temperatures fluctuate much less than air temperatures on land. Also, the ability for water to moderate temperatures explains why coastal areas have milder climates than adjacent inland areas.

            Another property of water is its ability to expand upon freezing. When water freezes the molecules become more stable and form a crystalline pattern, creating more space and less mass. In addition, water at thirty two degrees Celsius has no molecular motion. An example of this property is when ice floats on water. Water’s ability to expand upon freezing helps keep water under the surface of large bodies of water, warmer and suitable for life.

            The fourth property of water is its versatility as a solvent. Water is an effective solvent because it readily forms hydrogen bonds. Water is also known as the universal solvent because it can dissolve many things. Also, water is a polar solvent so it can dissolve polar solutes.  But water cannot dissolve strong polar solutes like oil.

            In conclusion, water is the substance of life that is why scientists look for water on distance planets as an indication of possible existence of life.

 

Colored Milk Lab

  

The night before class, I watched the video of the milk in motion lab online. In class my partner and I came up with a two part hypothesis. The first part of our hypothesis was that the dish soap is a type of degreaser, so it attacks the fat of the milk. The second part of the hypothesis was that milk is an acid so it reacts with dish soap because it is a base.

 

            To test this two part hypothesis, we created two different experiments. In the first experiment we placed 10 milliliters of creamer into a Petri dish and put three drops of both red and green dye, and then we placed two to three drops of dish soap. We saw that where the soap was dropped bubbles were formed in the creamer and moved the dye. We repeated this process three times and we got the same results.

 

 

            In the second experiment, we placed 10 milliliters of vinegar into a Petri dish and put 3 drops of both red and green dye, and then we placed two drops of dish soap. We repeated this process three times. Each time there was small reaction between the vinegar and the dish soap but nothing significant.

 

 

            In conclusion, the first part of the hypothesis is more accurate than the second part because the detergent reacted with the fat in the creamer and let the pigment in the dye spread throughout the creamer. But before the fat and the detergent reacted, the detergent reduced the surface tension and allowed the food coloring to move throughout the milk. Also the detergent reacted with protein in the creamer and changed the shape of the molecules and set them in motion.