Reflection on Stomach Acids

Lately in Biology we have been experimenting with stomach acids and what works to calm an upset stomach.  My group and I tested different types of antacids by placing two tablets into vinegar.  An antacid is any type of base or basic substance that neutralizes stomach acidity.  I learned that an acid is any substance that has a pH of six or lower.  Acids become less acidic when mixed in with a substance that is a base.  An acid increases the concentration of hydrogen ions, but bases lower the concentration of hydrogen ions, because they accept them.  A base is a substance which has a pH between eight and fourteen.  A base becomes less basic when mixed with acidic substances.  Pure water, on the other hand, is neutral because it maintains a pH of 7.  The pH is calculated in logarithmic units of ten in the acidity or baseness of a substance.  For example, orange juice is ten times more acidic than tomato juice, because orange juice has a pH of three while tomato juice has a pH of four.  

Antacids help calm the acids that are in your abdomen.  I found out that about the only difference in generic brands and name brands of antacids is the price.  So, next time you go to the store to buy antacids, don't fall for the expensive brand, because in all actuality they work the same. 

Acids in Your Tummy!!!!

Last Thursday we did a lab about stomach acids testing the different antacids.  Check out our AMAZING powerpoint we created! :)





After our lab, I learned that even the generic brands of antacids work the same.   Companies just want you to buy their product at a higher price, attempting you to believe that their product is better.

Properties of Water

Recently in Biology we have been studying the properties of water, and we did a lab focusing on three properties.  In the lab, we did a trial on the surface tension in water, using pennies.  The experiment required you to place as many droplets as you could onto a single penny without them falling off.  I learned that a penny can hold quite a few droplets because of surface tension.  In the next experiment we had to place a drop of water onto a piece of wax paper.  Using a toothpick, we had to split the drop of water in half.  As we were attempting to split it in half, the tiny droplet would not split; but it would simply just slide along the wax paper staying together which helped us examine the cohesion process.  The last part of the lab we experimented with a beaker of water, a string, and an empty beaker.  In this lab, Kelsea and I had to figure out how to take the water from the full beaker and run it down the  string to the empty beaker.  We figured out that in order to get the water to travel down the piece of string, we had to change the position of how the water was poured.  We finally discovered that if you hold the empty beaker directly below the string and beaker of water, and the full beaker, the water should travel directly down the string into the empty beaker.
While watching and observing the videos Water and Life: Overview and The Nature of Water, I learned many different things, along with definitions of certain words.  I observed that water is a solvent meaning it's chemical composition does not change when dissolved into another substance.  The molecular formula of water is H20 which means that the chemical composition of water consists of one oxygen atom and two hydrogen atoms.  I also found out there are two types of polarity which are bond polarity and molecular polarity.  Water exemplifies bond polarity because the oxygen atom and hydrogen atom are not evenly distributed among the two atoms.  They are closer to the oxygen atom than they are the hydrogen atom.  Water also shows molecular polarity because of it's bent shape.  Without a net "pull" in a direction, the molecule will not be polar.

                                                as shown above water molecules are bent




WORDS OF KNOWLEDGE

*Adhesion-The attractive force between molecules in one phase and different molecules in another phase.

*Cohesion-The attractive force between similar molecules in the same phase

-Sum of hydrogen bonds

*Hydrogen Bond-A weak to moderate attractive force between a hydrogen atom bonded to oxygen, nitrogen, or fluorine, and an oxygen, nitrogen, or fluorine atom on another atom.

-Usually represented by dotted lines

*Hydrophilic-Water-loving; easily dissolves in water

*Hydrophobic-Water-fearing; doesn’t dissolve in water

-ex: oil

*Polar Covalent Bond- A molecule where electrons are shared between the two atoms.  One atom is more electronegative than the other which causes the electrons to pull closer to it.  Partial charges are formed which creates dipole.

*Solvent-A liquid which dissolves another substance without any change in its chemical composition.

*Specific Heat-The amount of heat needed to raise the temperature of a 1-gram sample of a substance by 1 degree Celsius

*Surface Tension-The energy needed to increase the surface area of a liquid by a given amount.

*Electronegativity-The tendency of an atom in a bond to attract shared bonding electrons

European Corn Borer/Clinical Trial

The past few days in Bio 111 we have been working on and studying about clinical trials. I also did a virtual lab from the textbook called "How does the European Corn Borer Affect the Yield of Corn"?  designed to help with identifying dependent and independent variables.  I learned about a double-blind clinical trial which means neither the volunteer participating in the clinical trial nor the physician or doctor know what type of medicine or cure they are going to be using.   In the virtual lab I learned that certain types of corn resist pests better than others and that nowadays, corn plants have been genetically engineered and selectively bred in order to resist insect pests better.  I also found out that a control is the variable in an experiment which never changes.  I learned that with a low infestation of insects corn yields tend to be a bit higher and when the infestation levels are high, corn yields are comparably low.