Thursday, March 18, 2021

Study Habit Flow Chart

 The best study habit that I've developed through suggestion and experience is the ability to read without understanding. 

What???

I think that's one of the biggest challenges that I've faced in my limited time as a science student. My chemistry professor in the fall '20 semester said to read the chapter without working hard to understand it.

That is really hard for me.

What I'm learning, though, is that if I can plow through it and just read it and maybe learn some of the vocabulary before the lecture, that I can then go back and it will start to make sense. 

For example, in studying for a test, I'm going back and filling in my notes from class. The class moves way too fast to make detailed notes during the lecture. I find myself missing important information and discussion if I take too many notes, so I just try and get the highlights and make "bookmarks" of where in the PowerPoint it can be found. 

Now that I've laid that foundation, I am going back and filling in notes and making compare and contrast tables and it's all coming together.

Again, though, it starts with that first step of reading without understanding, which actually takes a good amount of fortitude because you keep saying, "What???" to yourself and the desire to go back and read and reread until you get it. 

Oh! And make questions about the things you don't understand, even if it's just, I don't get X main topic. Those become bookmarks for your mind and will actually help to reinforce the learning that comes from the lecture.

So: read without fully understanding -> form questions from the reading to take to lecture for discussion ->  take notes on the lecture and ask when your questions aren't answered in the lecture -> reread and make flashcards for vocab with new understanding -> review notes and fill in missing info and detail -> tables to compare and contrast concepts and processes -> flow charts to show the steps and components of a process

Wednesday, February 17, 2021

Dad pushed me out of the snow

Dear Dad, 

Thank you for telling me to have boards in my car in the winter. Because of your advice, at 1:30 in the morning, on my way home from a hockey game, when I was stuck in the snow in my alley, I had the wherewithal to remember the boards in my trunk and was able to stick them under my tires and get out of a bad situation. 

I love you, and I miss you. It is times like this when I know that you are still with me and always will be.

Tuesday, February 16, 2021

Pumping protons in the electron transport chain (ETC)

 I was having a really hard time with one aspect (okay, a few aspects) of the Electron Transport Chain.

Quickly, the ETC is a process by which most cells manufacture energy storage molecules called ATP. 

The whole point of the ETC is twofold: first, to move electrons across a series of complexes along a membrane (eukaryotes -> mitochondria; prokaryotes -> extra-membrane space); second, the action of the electrons "pumps" protons across the membrane which creates a proton gradient.

The point of having a proton pump that uses the energy released by the passage of electrons enables the process without expending chemical energy. Rather, it uses the attractive forces between electrons and protons through special proteins. 

NADH called an "electron carrier," although it actually contributes protons to the process, as well. The NADH drops two electrons into a protein complex. In a separate action, the complex is then able to take a hydrogen proton (the H in NADH) and, using attractive forces, pull it across the membrane space. 

By doing so, the electrons are used to pull the electrons to the ATP synthase complex where protons are forced back through the membrane and are picked up by an ADP to create a molecule of ATP.

If you care to read more, here's a good source:

https://www.ncbi.nlm.nih.gov/books/NBK26904/

Monday, February 15, 2021

Biofilm & Quorum Sensing

 Did you know that bacteria make the antibacterial medications (antibiotics) we use? That's right! 

Bacteria in nature make antibiotics that enable it to outcompete other bacteria. 

Biofilm is one example of how different bacteria work together for survival. It is a structure made of one or more species of bacteria that adhere together and form a colony that is covered by a polysaccharide substance, or EPS (extracellular polysaccharide substance.) 

As the bacteria collect, they perform a few collective functions. First, they establish channels they use to communicate (using chemical information), share nutrients, and pass waste products. 

Note that some bacteria use waste products as their nutrients! Does that seem gross? It does until you stop and realize that WE do that all the time. The best example is oxygen. Oxygen is a waste product of photosynthesis, the process by which plants (and other photosynthetic organisms) convert water, carbon dioxide, and sunlight into stored energy. 

As the biofilm accumulates, it also senses the environment in which it has found itself. Different bacteria have different genetic properties, such as the types of enzymes and antibiotics they produce. Once they have accumulated that information, growth ensues.

They can also pass along genetic material through the channels that enables the group to take on that trait.

Once growth ensues, the biofilm will actually deliberately shed some of the cells which then form another biofilm, and so on.

Biofilm can be both pathogenic and symbiotic. While they form on our teeth and can cause tooth decay, biofilm can be found in the gut and are integral to our digestive system. 

However, the biofilm does not become helpful nor harmful right away. We go back to the idea that they consider their environment which has a direct effect on what genes are used - think about enzyme production; they may need certain enzymes in one environment both another type in a place that has different nutrition, water availability, or other environmental factor. When the bacteria have all communicated their agreement, they will suddenly activate. This agreement through chemical communication is called "Quorum sensing." 

If you want to watch a really cool video about Quorum Sensing, this TED Talk discusses it through the phosphorescence of certain squid. https://youtu.be/KXWurAmtf78