Three Major Themes

The three themes that I can identify from this course are molecules, structures and function. The first several chapters we focused on had to do with the building blocks of life. What and how the simple pieces fit into the larger structures. For example we studied amino acids which are important for DNA/RNA structure. We then focused on structures and how they are built affects what role they will play in the cell, their function. For example DNA/RNA contains information based on what sequences they contain, they ultimately participate in the control of the functioning of the entire cell. And lastly, function. We studied several important cellular metabolic processes that carry out life sustaining reactions. For example an enzyme is coded for in DNA/RNA and once expressed has a role in glycolysis which provides energy for the cell. The themes from the material in this course are connected to each other because they build on each other. Each piece of information is important to gain the big picture of what is going on in the cell.

I have studied much of the material that we covered in this class in previous science courses. However, I have gained the big picture in this class. I now have a perspective of how reactions happen in the cell and why. Before this course gene regulation, metabolism and cellular respiration were disjointed pieces of information in my mind but now they flow and I can see how they are connected. 

Explanation To a Friend

When you eat carbohydrates they go into you digestive system and are ultimately broken down into simple sugars, the most important being glucose. Glucose is sent off to individual cells which take the glucose into their innards, the cytosol. In the cell every one molecule of glucose is transformed into two molecules of pyruvate by an energy creating process called glycolysis. The pyruvates are handed off to these things inside the cell called mitochondria which convert glucose into Acetyl CoA.

Inside the mitochondria Acetyl CoA is put through a process called the citric acid cycle where even more energy is created. During both glycolysis and the citric acid cycle hydrogen atoms are primarily handed off to a molecule called nicotinamide adenine dinucleotide (NAD+) to form NADH. There is another molecule with the same function abbreviated FAD+ that gets changed to FADH₂ when hydrogen is added. The NADH and FADH₂ are responsible for handing those hydrogen atoms off to the electron transport chain.

The hydrogen atoms, aka: protons are pumped across a membrane in the mitochondria by the reactions of the electron transport chain and are allowed to travel back across the membrane though an enzyme called ATP Synthase. These protons passing through stimulate ATP Synthase to create energy. The currency of energy in the cell is in the form of molecules called ATP when we say energy is created it means ATP is made by adding a phosphate to ADP and conversely when we say energy is used it means ATP is changed back into ADP by removal of a phosphate. The whole process from glycolysis to the electron transport chain creates about 38 ATP for the cell to use as energy.

More connections with past knowledge

It’s interesting to be in lecture and realize that not only have I learned the material before but now we will be analyzing it in a new light. The integrative biochemistry perspective has made so many connections for me. I’m glad to have taken this class at the end of my undergrad because it is serving me well as a reminder of all the other science/lab classes I have taken. There are some areas that I’m realizing I need to delve further into and this class has opened doors for the possibilities of research.

There was one moment in class that I specifically remember when one of these bridges between knowledge being made was when we were talking about glycolysis and gluconeogenesis. I made this connection with endocrinology about the autonomic nervous system’s fight or flight response. I realized that these two metabolic pathways, while they generally occur unnoticed, are more influenced by an individual’s environment than simply by what the body is in need of at a given time.