Honors Bio class 11

Today in class we talked a little about last nights homework and then spent the rest of class finishing the worksheet of our choice. I chose the worksheet where you compare different DNA of animals to each other, and record the differences on a table. The worksheet looked like this:

 

The table of differences

The DNA strands

 

At the end of the worksheet, we ranked the animals in terms of their position in evolution on the earth, and answered some questions on evolution. We concluded that the DNA of all these animals shared some similar characteristics that would suggest that they shared a similar ancestor. Some were closer than others such as, the zerbra and horse, or the chicken and turkey. This evidence helps to further prove the theory of evolution, and its role in earths history.

Honors Bio class 10

Today in class we talked about evolution and the importance of fossil evidence to prove this theory. We reviewed the process of uncovering a fossil and how fossils are formed through sediment and pressure so that the bones are hardened. Then we took a closer look at a particular type of transition fossil called the Tiktaalik. The Tiktaalik was a very important piece of evidence for evolution because it displayed the transition between a fish and a land animal. You are able to see the changes in its bone structure along its ribs, skull, "arms" and "legs." One can compare it's arm to the structure of a human arm, in order to observe the differences and similarities. Its ribs are also expanded like a humans, so that it can lie on its stomach and maneuver around obstacles better. This important change was prompted by the movement of the tectonic plates, which led to drastic changes in the environment. the Tiktaalik adapted because it was forced to live in shallower waters, which made land more convenient and readily available. Land also offered a larger diversity of food, such as insects, for the Tiktaalik to eat. After the lecture, we visited the museum to view the exhibit on the Tiktaalik:

test day

Today in class we took the test. Once finished we left for lunch.

Honors Bio Class 8

Today in class we had a test review on what would be covered on the test. We reviewed water and all its different components, such as adhesion cohesion and hydrogen bonds. We also discussed some basic chemistry and how to solve for valence electrons using only the atomic number (only two electrons in the first shell). Next we went over macromolecules and their properties: Polymers, monosachrides, amino acids, proteins, hydrolysis, and polymerization. DNA and RNA were also included and we were required to know how they differ. After the review we had a short quiz on what we had discussed.

Honors Biology Class 7

The first thing we did in class was go over the homework. This included the different structures of carbohydrates like glucose, proteins and fats, like lipids. We also wen over how each component builds and breaks bonds through the process of hydration or dehydration.

After this we were given the choice between two different labs, my partner and I chose to do the one called Who Took Jerell's IPod. First we tested vegetable oil, Glucose, starch from potatoes, powdered egg whites, and water for Glucose, Starch, Proteins, and lipids. After this we tested pretzel, butter, jelly, fat-free yogurt, and beans for the same properties. Once this was finished we would choose two different types of evidence, one liquid and one solid, to test  and solve the mystery. Here are some pictures:

Testing for glucose using Benedict's and heat.

Testing for for starch and protein using iodine and biuret.

Here is what we used to test for each property. Once finished, we used the different properties we had collected and compared it with the results of the liquid and dry evidence of the thief. we found that the the thief would have to have glucose, starch and lipid, making the thief responsible for butter and pretzel. We had solved our case :).

Honors Biology Class 6

Today in class we went over the cell and its components. Glycoproteins are integral proteins and help with the cell membrane, and cell--cell recognition. Phospholipids help to determine what can and can't enter the cell, especially those that lie within the phospholipid bilayer. Phosphate is a type of fat that also resides in the bilayer. Cholesterol allows the cell membrane to be fluid and helps with osmosis. 

After the lecture, we went over the house case that had been assigned to us the day before as homework. 

Given information:

High school senior

18 years old

Cross country runner 

After practice he began to vomit and had a severe headache. When he was brought to the hospital he showed signs of confusion and was extremely tired. 

With this information we set up the room to resemble the one in the show House. Each student was allowed to ask  two questions about the patient and the data was then recorded. Once we had collected all the data, we then worked on deciding what tests we would run to help come up with a diagnosis. At the end of the class Mr. Quick gave us the test results which helped to conclude the case.

Honors Biology class 5.

Today in class we went over the experiments we did last class and he had us draw graphs to help us better understand osmosis:

here is the graph for the average russet potato mass percentage change. We concluded that the potato is hypertonic and the solution was hypotonic because the mass increased as the molarity of solute decreased. We concluded the same thing for the sports drink because it displayed the same pattern:

 

After the review we talked about diffusion, and the two experiments we would be preforming in class. The first experiment required us to fill tubing with a mixture of 15% glucose, and 1% starch, and place it in a cup of pure water. After 15 minutes we would test the water and we if any glucose or starch had left the tubing (which acted like a semi-permeable membrane). The second experiment required us to use gel blocks and place them in the solution you were assigned (we got NaOH). we then measured the volume and surface area of the blocks before and after the experiment. After the experiment, we would also measure the depth of diffusion in each block.

 

Here are some pictures from the first experiment:

here are the glucose strips we used to test the solution and the water (the one on top is the strip we used to test the water). Brown = glucose, and Green = no glucose.

Benedicts is what we used to test the water for glucose after the 15 minutes had passed. we then mixed the benedicts with some of the water from our cup and heated it in a glass tube:

because it changed color, we concluded that glucose had left the tubing.

this is a picture of us mixing iodine with the water to test if any starch had left the tubing.

because the solution turned black after adding the iodine, we concluded that starch had not left the tubing.

 

Pictures from experiment two:

these are the cups filled with NaOH and the gel blocks.

this picture shows the diffusion of the NaOH into the gel after 15 minutes.

 

Honors Biology class 4.

Today in class we went over the concept of osmosis and diffusion. Osmosis is when water travels through a semi-permeable membrane from areas of higher concentration, to areas of lower concentration. Diffusion is kind of like the same thing but is not specific to water. It deals with a solutes concentration gradient, and how the solution travels from areas of higher concentration, to areas of lower concentration. After reviewing these concepts, we went into more detail and talked about what makes something hypertonic, hypotonic, and isotonic. A hypertonic solution that has higher osmotic pressure (or has more solutes) than another solution to which it is compared. A hypotonic solution refers to any solution which has a lower osmotic pressure than another solution (that is, has a lower concentration of solutes than another solution). Isotonic solutions are two solutions that have the same concentration of a solute. here are some notes from class:

 

After this we set up three experiments to help with our understanding of osmosis.

 The first experiment required us to fill tubing to with solutions that that had varied amounts of solute in it. We would then place this tubing into a cup of pure water and measure its mass after fifteen minutes or so. Here are some pictures of the first experiment:

 

The second experiment was where we cut up potatoes and placed them in covered cups of the different solutions. We would then come in later that day to record any changes in mass. here are is a picture:

 

The third experiment required us to fill tubing with a sports drink (we chose vitamin water) and place it in a covered cup filled with the different solutions. Once again we would later come back to see if there were any changes in mass. More pictures:

Today in class discussed water and its many properties. One of its most important properties is its ability to go through the process of cohesion and adhesion. Cohesion is the ability of water to bond with itself and adhesion is the ability of water to attach itself to something else. Water also has a special kind of bond called hydrogen bonds. Hydrogen bonds are weak and give water the ability to break bonds without using too much energy which is very important in living organisms. Water also has more heat capacity then other molecules and its boiling point is 100 degrees Celsius. Water molecules are special because they expand when they freeze and their atoms become more rigid. When frozen, its density also decreases because is mass decreases but its volume does not.

After the lecture, we did an experiment testing the the cohesion and adhesion of water. First we dropped water onto pennies until it created a convex surface:

Why convex?

because water uses cohesion to bond and grow on top of each other.

But why convex?

because the tangent angle at which water grows forces it to take a convex shape.

 

After doing this a few times he asked us to use a toothpick to prod the surface a few times and observe how the water interacted with it:

 

here we can see the process of adhesion taking place as the water molecules attach themselves to the toothpick.

 

After this we dipped the toothpick in some dish soap (surfactant) and poked the convex  surface:

 

 

althogh we had some trouble, we were eventually able to break the convex bubble.

 

Once the experiment was done we took a quick chemistry quiz and left for lunch :).