Control of Enzymes

As we know, enzymes break down molecules in our body; our body would not be able to break down things like lactose if it wasn't for enzymes. Phenylketonuria (or PKU) is a genetic disorder that is passed down from both parents. This genetic disruption causes the crucial metabolic enzyme PAH to be disrupted. Without this enzyme; one can accumulate very dangerous and very high phenylalanine levels in their brain.  This can cause mental retardation or epilepsy. PKU produces phenylalanine, an amino acid that is a building block for protein. When a doctor or physician thinks that an individual has PKU, they test for phenylalanine in that individuals blood. However, it is possible that high levels of phenylalanine in the blood would not be because of PKU, the doctors would have to be sure by performing other blood tests.
There are several symptoms of PKU, however, symptoms may not be noticeable while this disorder is developing. If a child has PKU; they usually have a smaller head than normal, epilepsy or retardation. There would be an overflow of phenylalanine causing the victims skin to have a musky oder. Deficiency in  tyrosine leads to a lighter skin and hair color.
This disorder is very rare, in fact, PKU appears in about 1 in 10,000 caucasians. To treat this disorder, the children must obtain a low-protein diet. They must stay on this diet as long as possible, some doctors even recommend that they stay on the diet for life.

Structure of Membranes

Cell membranes are composed of many phospholipids. There are two parts to a phospholipid; the head and the tail. The head is hydrophilic; meaning that it loves water. The tail is the exact opposite, it is hydrophobic. These opposing parts of the phospholipid contributes heavily to the structure of the cell membrane.

Several phospholipids make up the cell membrane. A hydrophobic phospholipid consists of 16-18 carbon, hydro carbon backbone. They also contains small amounts on oxygen.

Fatty acids are generally 16-22 carbons long. There are two types of fatty acids; saturated and unsaturated. Saturated fatty acids have no carbon-carbon double bonds saturated with hydrogen. Unsaturated fatty acids have one to three double bonds along the backbone carbon chain - "kinks" in the carbon chain. Fats are storage for energy and insulating molecules. They contain twice as much energy as carbohydrates. Unsaturated fat has one unsaturated fatty acids. Saturated fats have none. 

The bending of the tail is a "kink".

Phospholipids contain only two fatty acids attached to a glycerol head. The third alcohol of the glycerol forms an ester bond. As a triprotic acid, the phosphate head has the potential to form ester links with a variety of other types of molecules like carbohydrates or amino acids. 

Micelle Formation

Liposome Formation

Steroids are four fused carbon rings. They include many hormones as well as cholesterol. Cholesterol is a major player is cell membranes. Steroids restrict the movement in fatty acids tails. 

The extracellular surface of the cell membrane is made of carbohydrates attached to lipids and proteins.
The proteins in the membrane enable the membrane to carry out normal activities. Proteins on the extracellular domain surface generally involve in cell-cell signaling and interactions. Domains inside the membrane move molecules across the membrane.

Below is a Fluid Mosiac Model I drew with a peer. It shows, further, how membranes are structured.

Diffusion and Osmosis

We also performed a lab to see how strong the membrane really is. We took a glucose/starch solution and put it into a rectangular, thin baggy. We put iodine water into a cup and placed the glucose/starch baggy into it. We tested each solution separately before placing the baggy into the cup. Of coarse, the glucose/starch solution came out positive for glucose. The iodine/water solution came out negative for glucose. We let the baggy sit in the cup for a couple days before coming back and testing each solution for glucose again. Both the starch/glucose and the iodine/water came out very positive for glucose. The starch glucose had also turned colors from a foggy white, to a dark dark blue color. Also, the iodine water turned a lighter color. Because the glucose/starch solution turned that blue color, this signifies that the polysaccharide (starch) is being affected by the iodine. This means that both the iodine solution as well as the glucose/starch solution are being affected by one another; they are mixing together in the cup as well as in the rectangular baggy. This part of the lab is a great example of diffusion. Diffusion is better known as migration; or an intermingling of molecules.
In the second part of the lab, we are mainly looking at osmosis. In four cups, all filled halfway with water, we placed four rectangular shaped baggies filled with different substances. In cup one; we had a baggy of corn syrup/water mix. In cup two; we had a baggy of sodium acetate/water mix. In cup three; we had a baggy of crushed antacid tablet/water mix. In cup four; we had a baggy of sodium bicarbonate/water mix. Initially, me and my peer weighed the baggies before they were placed in the cups filled halfway with water. The antacid baggy weighed 13.43g, the sodium acetate baggy weighed 13.74g, the corn syrup baggy weighed 11.93g, and the sodium bicarbonate baggy weighed 11.66g. An hour later, we came back to weigh them again to see if any water was coming in yet, and indeed there was. An hour later the antacid baggy weighed 14.74g, the sodium acetate baggy weighed 23.09g, the corn syrup baggy weighed 15.88g, and the sodium bicarbonate baggy weighed 12.09g. There was a dramatic change, especially in the sodium acetate baggy(even in appearance, it was very noticeable). The water had moved into the baggy very quickly as I had predicted because of how small the water molecules are. By the next day, the baggies had evened out, showing us that osmosis had, indeed, taken place. Below is a graph showing the changes that the baggies underwent.

The Basics of Molecules

In my biology class, we are learning about molecules and how they build up and break down. We are doing a web activity to study these concepts.
A macromolecule is a very large molecule that contain hundreds or thousands of atoms. A monomer has a low molecular weight and is capable of reacting with other monomers to form a polymer. Monomers are mainly sugars, amino acids, fatty acids, or nucleotides. A polymer has a high molecular weight and is derived mainly by the condensation of many smaller molecules. The four main types of macromolecules are: proteins, lipids, carbohydrates, and nucleic acid.
Macromolecules are formed when monomers come together to create larger chains of polymers. Monomers  join together through a condensation reaction where a covalent bond is formed between two monomers and also a water molecule is formed. Polymers are broken down by hydrolysis reaction. In hydrolysis reaction, the water molecule breaks the covalent bond that holds the two monomers together. The specific name for the bond between simple sugar monomers is called condensation reaction. The enzyme that joins monomers together is called a polymerase enzyme. Sugar is stored as glycogen in the human body as spirals and branches. Plant foods are essential to animal life because they contain many carbohydrates. The digestion of starch by animals starts in the mouth by chewing it mechanically and chemically breaking it down with saliva, in continues in the small intestine with pancreatic amylase.

Ph Lab

In this lab, we tested a number of anti-acids for their PH levels. The PH scale measures how acidic or basic something is. Most anti-acids are very basic because you stomach is very acidic. Basically, we are testing to see which anti-acid is more basic.

We tested: Peppermint antacid 400mg, Equate Regular 500mg, Rolaids 550mg, and Extra Rolaids 675mg(higher strength Rolaid). 

PH level of each:

Peppermint Antacid - 5

Equate Regular - 4 

Rolaids - 6

Extra Rolaids - 5

Carbohydrate ID Lab

In the carbohydrate lab that was performed in my biology class, we studies monosaccharides, polysaccharides and disaccharides. The three elements that are present in carbohydrates are carbon, oxygen and hydrogen.
Two examples of monosaccharides:
1.) Glucose
2.) Fructose
Two examples of disaccharides:
1.) Lactose
2.) Sucrose
Two examples of Polysaccharides:
1.) Cellulose
2.) Glycogen
In water, there are two hydrogen atoms for every oxygen atom. In carbohydrates, there are 6 hydrogen atoms and 12 hydrogen atoms.
We know that mono means one; di means two; and poly means many. We use these terms in describing the three types of sugars because:
Monosaccharides; contains one monomer
Disaccharides; contains two monomers
Polysaccharides; contains many monomers
We can tell, using the Benedict's solution, that a monosaccharide is present because the solution will turn either a cloudy orange or white color. We can tell, using the iodine solution, when a disaccharide is present because the solution gets heavily darker. We can tell, using the iodine and Benedict's solution, when a polysaccharide is present because there is no change in the solution.
Foods that contain:
Monosaccharides- Fruit
Disaccharides-Corn Syrup
Polysaccharides-Cheerios

Properties of Water

In our classroom, we performed a lab to evaluate the properties of water. In the first part of the lab, we used a dropper to see how many droplets of water we could drop onto a single penny. It held to just about 30 droplets, forming a large bubble shaped droplet of water sitting atop the penny. The property of water that is being evaluated here is a hydrogen bond. Hydrogen bond keeps the water as a bubble on top of the penny. This is important regarding living organisms because a hydrogen bond is very important when we talk about the replication of DNA.
In the second part of the lab, we placed a single droplet of water onto a piece of wax paper. We then tried to chop it in half, I did manage to chop the droplet in half after several attempts. It creates two individual small, bubblie droplets of water. The property of water that is being evaluated here is cohesion and adhesion. Cohesion is how the particles in water unite together, and adhesion is the attraction between unlike bodies, for example the attraction between the water and the penny.

How science works and Biotechnology

In my biology class I went over the normal scientific method, some things that I got out the activity is that in most scientific experiments, repeating the same steps over for new information is necessary and that conclusions are revisable if they are warranted by the evidence.
I did an experiment over how corn with the bug repellent grows worse or better than the regular corn. The independent variable was the bugs, the dependent variable was the corn and the control was the fact that it was the same corn grown. In the experiment you would weigh the corn to see which one was more rich that was grown with or without the bugs. It just went over the basic scientific method procedures and it really let me get the hang of doing experiments and understand which elements are the independent variable, dependent variable, control ect.
In a clinical trail, in my point of view it is basically the control group vs. the group that is being experimented on. The clinical trail activity showed me how experiments are performed on people. In a clinical trial, people have to volunteer. The particular trial I viewed was a double-blind placebo experiment. It was to determine the long term efficacy and safety of asenapine in the schizophrenic patient population. It described how this experiment would prevent relapse after long-term treatment of schizophrenia.