Organization of a Cell

Originally I drew an image of a cell, but seeing as how mobile phone cameras and lightly drawn cell membranes don’t go well together, a picture from the inter-webs will have to suffice!

Let’s start simple.

The cell membrane is a semi-permeable layer. It controls what goes in, and what comes out!

Then we have the nucleus. It is where the DNA is kept, and RNA is “written” or transcribed. Nuclear pores allow proteins to enter and RNA to exit.

Next we have the ribosomes, where RNA is translated into protein. They float freely in the cytoplasm, but are also attached to the ER (or endoplasmic reticulum).


Now for the cytoplasm. It is the material between the cell membrane and nuclear envelope.


Also, there is:

The lysosome- the digestive system of the cell which breaks down molecules.

Mitochondria- the part of tissue cells which are the main source of energy for the cell.

Golgi bodies- these change molecules and divide them into smaller membranes or vesicles.

Vacuoles- the single-membrane organelles that transport.

Microtubules- the parts that function in cell division.




In order to better understand the procedure of osmosis better, I performed an experiment.

It required two unfertilized chicken eggs, vinegar, distilled water, and salt.

First, I soaked the eggs in vinegar for about 72 hours, which removed the shell, leaving the sac of yolk and whites.

Next, I poured distilled water in egg 1, and salt water in egg 2.

After a few hours, this was my result:

On the left is the distilled water egg, on the right is the salt water egg.

There is an obvious illustration of osmosis in these eggs, as it shows that molecules have passed through semi-permeable membranes.


1. What enzyme is most commonly defective in people with phenylketonuria?
PAH is the enzyme that is most commonly defective. PAH is phenylalanine hydroxylase. It processes phenylalanine to tyrosine. PAH change was first detected in a single-base change.

2. What reaction does this enzyme catalyze? (What is the substrate and what product is produced?)

It catalyzes the phenylalanine catabolism, in which phenylalanine is changed into tyrosine.l

3. Describe the symptoms of phenylketonuria.
1. Skin lesions.
2. Lower IQ.
3. Emotional issues.
4. Mental/Growth retardation.
5. Physical malformations.

4. What causes the symptoms of PKU, the lack of a substance or the buildup of one?
Both. Either a buildup of substances that may cause harm, or a lack of molecules. The buildup is phenylalanine, a natural substance.

5. How common is phenylketonuria? How is it treated?
It occurs in 1 in 10,ooo births.

It is treated by a low protein diet, seeing as how phenylalanine is in our protein.


1. Describe the primary structure of collagen. What are the major amino acid components?
 1s of C(3Helix)= 2A(P/HP)+AG(rep)
Translation: The primary structure of collage(the triple helix) is 2 Aminos(either proline or hydroxypoline) and the amino glycine, and then it repeats.
2. What role does vitamin C play in collagen formation? What happens when a person does not get enough vitamin C in his or her diet?
Hydroxyproline and vitamin C make construction happen, vitamin C ultimately providing in the oxygen.
Hydroxyproline minus vitamin C results in signs of scurvy, very damaging.

3. Describe the quaternary structure of collagen (the way in which the polypeptide chains are arranged).
The quaternary structure is made of 3 left hand helices twisted in right hand coils.

1. What is the main symptom of osteogenesis imperfecta?  What are some other symptoms that people with OI may have?
The main symptom of osteogenesis imperfecta is fragile bones that break easily. Some other symptoms are muscle weakness,  fatigue, and short stature. Bone deformations also come along.
2. Type I osteogenesis imperfecta causes fewer problems than the other forms. How does the collagen structure in Type I OI differ from that of the other types?
The collagen structure in type I osteogenesis imperfecta is completely normal, thus the fewer problems in it than in other forms.
1. Describe the role of collagen in bones. Why do collagen problems lead to bone problems?
Collagen, from what I understand, is like a supportive, strong, elastic frame.  Without it, bone is a cinder block. It can be broken easily with a small amount of pressure due to the brittle nature. If there are collagen problems, it may break much easier. Imagine if a vertebrae broke. It would collapse, add pressure, and break the next one, and the next. Major problem. Like a fighter, bones need strength, and resilience.

A Letter of Divine Arsenic

I smell the faint scent of bitter almonds.

And feel a tad bit scared.

Dear Jane Austen,

From the most professional stance, I would like to apologize sincerely for giving you that medication for your joint pain. How was I to know arsenic would kill you? With the time machine my colleague created, I have traveled forth in time in order to find the true performance of arsenic! All for you, my dear. And the couple dozen other patients I provided medicine to… That’s beside the point though. Miss Austen, I am now in a world of strange clothes and romantic affairs obtained by making one’s hair appear as a rather questionable bird. There are buildings taller than you could ever imagine, odd devices gentlemen and ladies stare at, and yell into! The language is rather appalling, and I’ve yet to meet one nearly as well-versed as yourself. I have found after sneaking around in an endless amount of doctoral facilities that arsenic is quite, quite dangerous. But you should already know that, good heavens… I mean… Bloody hell. I mean… Oh my, I’ve yet again let my words get the best of me. Please forgive me for my insolence! As well as my crude wording. Returning to our  previous topic, arsenic is said to affect the interrupt the process of energy-making. This may defy what you believe in, but it’s also quite difficult to believe that you may read letters when you are dead. Your brain, and heart system, were eventually disrupted by the collective mass of arsenic built up in your system. Yet again, my apologies… If caught early, you might have survived! Pray don’t think of me as imprudent… There is a purely delightful idea referred to as ATP. Rather endearing how blunt and lazy the people of these days are. It is adenosine triphosphate! Magical name, is it not? It amazes me, as a talented doctor, to think that others could be more wise than me and come up with such a nonsensical name! It travels through pathways as if through roads. Arsenic seems to block this, and lead to organ failure. Amazing, is it not? Imagine all the damage one could do with arsenic, and- Yet again I have spoken too much… To say it frankly, your bits of energy were all used up and hurt, making it so you could perform not even the simplest functions. Now that you know that, I must show you something else that I learned! This is called a “smiley” as if it were a smiling face. 🙂 Quite remarkable! Yet again, please forgive me. Use the smiley well, it has much power.

                 As  Mr. Darcy would say, I love you most ardently. Take care Miss Austen!
Sincerely, Your Doctor.

Cystic Fibrosis

I’ll start with the pain of cystic fibrosis.

What is it?

Cystic fibrosis is a genetic disease. It causes mucus build up in various organs of the body. The lung and pancreas are most affected.  Bacteria gets stuck in this mucus, and leads to infection. Multiple systems are blocked, including the digestive system. Lung damage is all too common for those with CF.

This is a healthy lung.

And this, is a CF lung.

What are the symptoms of CF?

According to, they are:

  • “Very salty-tasting skin
  • Persistent coughing at times producing phlegm
  • Frequent lung infections, like pneumonia or bronchitis
  • Wheezing or shortness of breath
  • Poor growth/weight gain in spite of a good appetite
  • Frequent greasy, bulky stools or difficulty in bowel movements
  • Small, fleshy growths in the nose called nasal polyps”

How common is it?

30,ooo children and adults in America are affected by Cystic Fibrosis. It is the most common among Caucasians.

How is it diagnosed?

It is diagnosed by a sweat test (where the amount of chloride is tested) or a genetic test.


Specific channels are supposed to keep mucus moist, but in CF, the chloride channel is blocked, letting the mucus dry and build up.

Just exactly how much damage can it do?
Here’s a picture to give you a brief idea.

There are several medications, including mucus-thinners, antibiotics, and anti-inflammatories. Therapy is also available. One of the best treatments is said to be coughing, to get the mucus out. Parents may encourage their children to sing, exercise, or laugh to help get the mucus out.

Many support groups exist.


Just because a cure hasn’t been found doesn’t mean there is no hope.
A cure hasn’t been found YET.

A group of CFers wrote and sang this song. Cystic fibrosis isn’t just a defect. It can define the entire life of those who are affected by it. I can’t completely understand it because I am not affected by it, but with hope, CFers will be able to define their own lives, and, breathe.



Membrane Structure Tutorials Notes and Questions

Membrane Structure Tutorials

1. Go to and read the tutorial on the many types of molecules that come together to make a cell membrane.

Take notes as you carefully read the web page and watch the animations.  This will be in place of a lecture on this topic so make sure you read all sections and watch all the animations provided until you understand the material.

  • Cell=Made of 2 environments, hydrophilic aqueous cytoplasm, hydrophobic lipid membranes.
  • 3 members of fat involved, fat, phospholipids, and steroids.
  • Lipids hydrophobic because of cell structure.
  • Lipids protect.
  • Membranes=Asymmetric.
  • Proteins embed in fluid matrix.
  • Semi-permeable membrane.
  • Unique and various collections of proteins.

2. Go to
Read through the tutorial on membrane structure to see how the variety of molecules fit together in the fluid mosaic model. As quizzes appear during this tutorial, type in the questions they ask and the correct answer that you chose.

Quiz Questions and Answers: