Visual Learning for Anatomy & Physiology

20 02 2009

Last semester, I completed a year-long course of Anatomy and Physiology. I considered it quite a feat since the class required so much effort to memorize bones, muscles, tissues, veins, arteries, etc! I’ll provide an example:

Chapter 5 of a particular anatomy textbook discusses histology. It lists seven types of connective tissue (CT) within eight pages: adipose CT, fibrous CT, elastic CT, reticular CT, cartilage, bone, and blood. You have to memorize what these look like, as well as what sort of fibers (i.e. collagenous, elastic, and reticular fibers) and cells (i.e. fibroblasts, macrophages, mast cells, etc) they contain, where they are found in the body, and role they play within their location. Once that task is completed, you must go over other topics within the chapter including epithelial cells (i.e. simple squamous, stratified squamous, simple columnar, pseudostratified columnar, simple cuboidal, transitional, etc.), glands, as well as muscle (skeletal, visceral, and cardiac) and nerve tissue.

Overwhelmed? I’m starting to sweat just typing out all these concepts! Reading through an entire chapter front to back is not useful in preparation for exams-your brain cannot retain the enormous amount of information contained in its pages in one attempt. Textbook authors realize that their pages contain A LOT of information. This is why they include so many pictures and diagrams condensing a subject they spend four pages explaining. My advice to students is that they take full advantage of these useful tools.

I am going to share how I learned to study for this course using images contained within my anatomy and physiology text. Anatomy and physiology courses are comprised of two segments: lecture and laboratory. Lecture exams focus on a student’s level of knowledge with material covered, while laboratory exams require one to visually identify what is discussed in lecture. During my first semester, I spent too many stressful hours attempting to study for the two separately. I learned to condense by combining visual study with definitions. Here is an example. Below is a photo of adipose connective tissue.

The explanation for this connective tissue spanned two pages. I skimmed through it once, never had to back to it again, and received an A on both the lecture and laboratory tests covering this subject. How did I do it? Whenever I study a topic in anatomy, I seek to answer these four questions:

What is this?

Where is it found?

What is it comprised of?

Why it is it important?

When a solution to these problems was discovered, I immediately wrote it down next to the picture. For example, the adipose tissue contains collogen, elastic, and reticular fibers, as well as fibroblast cells. I would label these items, and under it write their definitions. Within the margins of my text next to this page I also wrote “ located under epithelial tissue,” “surrounds capillaries” “has macrophages” “plays role in inflammation” “holds tissue fluid.” My method worked for me because it combined and condensed. Time and energy were spared when two pages (out of a 30-page chapter) of an explanation were reduced to a single picture with some words around it. Whenever I needed to prepare for an exam, I would refer not to my text, but the photos within my text. In addition, my studying style allowed me to combine preparation for lecture and laboratory exams. I learned what adipose tissue was, and why it was important simultaneously.

 This is a great visual tool for studying-try it!

In summary: Find a diagram or photo within a chapter that condenses a particular discussion within the text. Find the information you need (What is this? Where is it found? What is it comprised of? and Why it is it important?), write it in/around that picture or diagram, and refer back to it when studying instead of the text.

Photo from: Hoehn, K., & Marieb, E. (2007). Human anatomy & physiology. Pearson: New York





The Future of Energy Production?

15 12 2008

The Future of Energy Production?

E. coli does not merely exist to infect our water stores, petting zoos, and, more recently, America’s supply of tomato and jalapeño pepper crops. These virulent types of E. coli give the bacterial species a bad name. E. coli, in actuality, contributes greatly to human health. For example, did you know that the organism colonizes within your large intestine? It synthesizes vitamin K (you need this to coagulate your blood), and provides protection from pathogens within the bowels since its presence leaves little resources for harmful bacteria to grow and thrive. In addition, E. coli is utilized to produce vital medications such as insulin and penicillin. E.coli is cool.

I came across a recent article that discusses a recent breakthrough in biotechnology concerning E.coli. Researchers have found a way to program the bacteria to produce gasoline as a by-product of metabolism. It’s one way to reduce our dependence on foreign oilJ.  Check it out:

 

http://www.cnn.com/2008/TECH/science/08/12/bug.diesel/index.html?iref=newssearch

 

-Melissa Reardon





Aerobic Respiration

3 11 2008

Solution to Aerobic Respiration

Original question:  Without oxygen, life dies. However, the molecule is not found within the pathway of glycolysis, the first step of aerobic respiration, or the Citric acid cycle (CAC). Why does body need oxygen? In, other words, what happen to body cells of oxygen supply is cut off?

 

To answer this question, one has to essentially “think backwards” about what she knows about cellular respiration. You should have a diagram of the CAC and electron transport chain handy. Reference the two listed below:

student.ccbcmd.edu/…/cellresp/fg17.html

student.ccbcmd.edu/…/energy/fg5.html

 

Information you should know…

1.      Oxygen is the final electron acceptor within the electron transport chain. It takes the electrons (along with the incoming H+ from the ion channel within ATP syntase) to form water, a product of cellular respiration. Think back to basic biology:

Glucose + O2 CO2 + H2O + ATP (energy)

Please review the movement of protons (H+) and electrons through the system. Know orders of complexes. Practice Question: Why does FADH2 produce less ATP than NADH?

2.      What is needed to begin the process of electron transport? NADH and FADH2! These reduced coenzymes (Look back to your diagrams!) donate electrons and protons (H+) to the chain. When the coenzymes give up these elements, they are oxidized back to the forms NAD+ and FADH+. Where do they go (The answer lies in one of your provided diagrams)?

The final answer to this problem is below, but based on the information presented try to come up with a solution on your own. For better understanding, follow along with the diagrams above as you read.

Oxygen is the final electron acceptor form original “donators” FADH2 and NADH. When these coenzymes give up electron and protons (H+) they are oxidized to FADH and NAD+, and  return to the CAC. There, they commence their role as oxidizing agents for intermediates such as malate and succinate and are converted back to FADH2 and NADH. Once again, these reduced coenzymes return to the electron transport chain. At the electron transport chain, they send electrons and protons (H+) through the system providing the energy to drive ATP syntase.

If oxygen is eliminated, FADH2 and NADH cannot be oxidized to FADH+ and NAD+ as there is no final electron acceptor available. Hence, the electron transport system stops. When this occurs coenzymes (NAD+ and FADH+) are not available to oxidize intermediates of the CAC so that they can return to the electron transport system to drive ATP synthesis. Hence, the elimination of oxygen disrupts the CAC. In conclusion, if oxygen is not available synthesis of ATP stops, and the body dies.

Notice I did not connect glycolysis to this model. How would the cut-off of oxygen affect this pathway? Can the body survive on glycolysis alone?

 

Next Question:

What kind of reaction is oxidative phosphorylation referred to as? Where is it seen in metabolism? Explain the process. How is it essential to the example you provided?

 

 

 





Solution to Metabolic Mypathy

28 10 2008

Solution to Metabolic Mypathy

Information one must be familiar with to answer this question:

1.            What is phosphofructinase?

 

Phosphofructinase is an enzyme involved with step three of the glycolysis pathway. It is responsible for catalyzing the addition of a second phosphate group onto fructose-6-phospahte to yield fructose-1,6-biphosphate.  This enzyme is a major point of control for this pathway. Phosphofructinase is allosterically regulated by ADP and AMP to inhibit glycolysis, as well as ATP and Citrate to encourage glycolysis (how does this process work?).

 An important fact to note is that the action of phosphofructinase leads to the formation of a molecule (due to its two phosphates) that will be split into two carbon intermediates which will form two pyruvate molecules (Remember this? Look back to the diagram of the glycolysis pathway in your textbook. The removal of the phosphate group from glycolysis’s final intermediate, phosphoenolpyruvate, is removed to form ATP and pyruvate- needed products for the continuation of aerobic respiration).

 

2.            What is myoglobin?

 

Myoglobin is a muscle protein that stores oxygen within muscle tissue as a reserve for respiration. It will appear in urine of muscle tissue dies (What absent element results in tissue death? ATP! Can you connect this with Metabolic Mypathy?)

 

3.            What is exercise intolerance?

Exercise intolerance is the inability of a person to use his/her muscles for an extended period of time (What does the body need to produce muscle movement? ATP! Muscles require a ton of it.).

I hope, by this point, you have solved this puzzle.

If phosphofructinase is unable to complete its role in step three of glycolysis formation of the bi-phosphate intermediate which leads to the formation of two carbon intermediates which leads to the formation of pyruvate does not occur. When this occurs Citric acid cycle cannot commence, NAD+ and FADH+ are not reduced,  NADH and FADH2 do not enter the electron transport system, and no ATP is produced (a mouth-full, isn’t it?). Hence, in muscle tissue, the absence of phosphofructinase results in the absence of ATP. Without ATP muscle dies. This explains the lack of muscle strength and release of myoglobin.

Also, this disease cannot be treated with ingestible enyzme replacement since the stomach contains powerful digestive enzymes that break down protein. Phosphofructinase is a protein.

That was not bad, right? Here’s the next question.

Aerobic Respiration

Without oxygen, life dies. However, the molecule is not found within the pathway of glycolysis, the first step of aerobic respiration. Why does body need oxygen? In, other words, what happen to body cells of oxygen supply is cut off?

 

By Melissa Reardon





environmental careers

24 10 2008

Hey environmental fans and majors,

I just found a couple great sites while I was looking for career/internship listings for environmental science. It’s such a huge field, I know it can be difficult to narrow it down to a specific career or to even know what’s out there. Here’s the links:

http://www.environmentalcareer.com/

http://www.khake.com/page46.html