Ascorbic Acid

Hey peeps, so whats good? We have been having some labs for biochemistry and the most recent one was to determine the percentage of ascorbic acid (vitamin c) in fruit juice. I went on you tube and found various methods used to demonstrate this and i picked the following so that you could compare the video’s method and the next method I would explain to you.

So ascorbic acid is a water soluble vitamin which is needed for growth and repair of tissues. The vitamin also helps the body to make collagen and a lack in it can lead to a disease known as scurvy. In this experiment the juice is acidified with glacial acetic acid and then water is added to this solution  Metaphosphoric acid is then added to this mixture and the solution transferred into a burette. Metephosphoric acid is composed of phosphorous and three oxygen. The acid serves to protect the vitamin c in the soloution against oxidation by the atmosphere. The solution in the burette is then titrated against dichlorophenolindophenol. This is a violet-blue solution which  turns colourless when it is reduced. So once enough ascrobic acid is added to the conical flask the colour change will occur and the titre value can be taken.  (Titre- difference between final and initial volume of the burette after the titration).

In the video the ascorbic acid in the presence of iodine is oxidized. Sodium thiosulphate is the oxidizing agent.

So it is the same concept but different reagents. In biochemistry there is not only one way to get to the finish line. The race is not for the swift but those who endure to the end.


Hope I was of some help people. Enjoy!


Multiple choice question 1

Good night people, or should I say good morning, because you might be in a different part of the world than me. So I have been talking to you for some days now and I have never actually given you any study guides for biochemistry. Well the first thing that my teacher says is that practice and constant studying is key and trust me he knows how to enforce this rule, as we have a quiz every week, but people keep going over the material, every day. Keep drawing the structures. I know that its hard and you have a load on your plate, trust me I know, as its our university ‘s joy to put one test after the next after the next or even on the same day. Just keep at it! Keep pushing for the best. I have compiled a simple test just to help with the basic revision:

1) The main storage polysaccharide for animals is _____________.

a. glucose





2.________ is released to lower high glucose level.





e. cellulose

3.What is the major component of cellulose?

a. alpha glucose

b. alpha mannose

c. beta-glucose



4. Approximately how much glucose does the brain use per day?

a.120 g

b.131 g

c.982 g

d.1 g

e. 0.1g

5.Which is an example of an aldotriose?



c. glucose


e. glyceraldehyde

6.Another name for a chiral carbon is a/an ______

a. 3d carbon

b.asymmetric carbon

c.linking carbon



7.D-Glucose and D-mannose is an example of ________.




d. aldotrioses


8.What two monosaccharides combine to form sucrose?

a.glucose and glucose

b. amylose and cellulose

c.glucose and fructose

d.glucose and galactose

e.fructose and galactose

9.which of the two is starch made up of?

a.fructose and galactose

b.amylose and cellulose

c.ribose and ribulose

d.cellulose and an aldotriose

e. amylose and amylopectin

10. Which test is used to test for reducing carbohydrates?

a.bial’s test

b.iodine test

c.benedicts test

d. Biuret test

e. Hydrogenation

So try the quiz out and see how much you have learned. Remember to keep testing yourself, if you cant answer the question, go back and learn the material and come and try again.

love peace chicken grease

Proteins and amino acids

Hey people, so where did I leave you last time? Oh yeah at amino acids and proteins. So the last video was a pretty good introduction to the different kind of protein structures that there is out there. As usual I am going to link you with the video that my biochem teacher created and then kinda pick out some major interesting points.

So there are four major structures for amino acids and they are the primary, secondary, tertiary and Quaternary structure. These are pretty simple to understand. The primary is just the sequence of amino acids. Remember in a previous post I kept rambling on about how the amino acids come together to form proteins and how there are twenty different amino acids. Well the basic thing is exactly how these amino acids come together to produce the over all protein. All protein have primary structure.

The secondary structure is basically the folding of the protein chain by hydrogen bond. Hydrogen bonds are formed when an hydrogen is connected to an electronegative ion ( an ion who wants to hog all the electrons in simple terms), so the hydrogen is left kinda positive ( lacking electrons, being electron deficient). So the hydrogen attracts to another electronegative ion who has a surplus of electrons. Hydrogen bonds are very weak except for when there are alot of those suckers. So when there are a lot of hydrogen bonds alpha helix and beta pleated shapes are formed. These are the two secondary structures of proteins.

Tertiary structures form from a spiral arrangement of amino acids. These is normally because of hydrophobic forces. Other bonds that play a part are sulphur bonds ( the strongest type of bond). Hydrophobic forces occur when non polar groups fold inwards to minimize their contact with water.  The hydrophilic groups are left on the outside. This causes another folding i proteins.

The last structure is Quaternary structure. This is the simplest one in my opinion. This is just how how polypeptide chain interacts with another polypeptide chain in a protein. One of the most common examples used to explain Quaternary structures is hemoglobin. Hemoglobin is made up of four sub units ( as seen in the picture).hemoglobin

That’s about it people. Have a good one!

Please note picture was obtained from another blogger:

Amino Acid and Protein

Good night my lovely biochem individuals,

Well my body have no longer been taken over by the evil virus, so i am back up and running on my feet. Well atleast i think that I am, he or she or it might still be hiding out somewhere in my body, waiting until I am weak and feeble to attack again and take over the world, one human at a time! Na I don’t think so, maybe it was just the common cold.

So at the beginning, things were a little rushed, and I didn’t get to fully explain some details, and as you and I know we are both pressed for time,so to resolve that problems, I am going to start putting up you tube videos, that my biochemistry teacher made and will discuss some general content in it , how it could of been improved for biochemistry students like yourself and add some general content to it.

So in general the video,gave an introduction to amino acids and proteins. Gave a general overview of the five types of amino acids R groups that are present: non polar,polar, aromatic, positively charged and negatively charged. Then it went on to give us the twenty common amino acids associated with humans and the abbreviations for their names. Now I sat there thinking they can not possible expect anyone to learn all of these names and abbreviations ( well not at this level, but if you going in to depth it would look pretty amazing if you know all the amino acids) so I went on a search to find something to remind me of them.  So I went on a search and came across this other blogger who came up with a way. So I am going to try it after I am finish here. Here is the cool link:

Tell me if you have any luck at all!

Then we went on to talk about a test to indentify amino acids and proteins. The one to identify amino acids is ninhydrin ( a clear solution of ninhydrin turns purple in amino acids) and to biuret test to identify proteins ( a blue solution of Biuret turns purple in protein). There is an exception to the ninhydrin test though: proline and hydroxy proline do not turn purple but yellow and this is from the account of there alpha amino group being part of a ring.

Did some thinking and I know, not many people know how to distinguish betwen proteins and amino acids. So once again I went on you tube and I came across this: http://

However, I think that she missed the vital step of explaining the chemical conversion of an amino acid to protein by a peptide bond. So the next time we meet I am going to go into that a bit.

See ya later people, please enjoy!

Carbohydrates countinue

Hey guys,

So where was I on our road to biochemical knowledge? Ohh yes, the glycosidic bonds forming on to connect two monosaccaharide. Well i am sorry to say that I am not feeling too much of myself tonight as a virus has taken over my body and I am now being held hostage as a breeding host, so I am a little under the weather. However I will not leave you hanging and will try and impart on you at least some knowledge for thought to end off this weekend.

I hope you looked at the glucose video. How was it? Was is very informative. I still can not figure out how to insert pictures into my blog but I will pretty soon and then you would be able to have animations to exactly what i am saying.

So there are two forms of glucose, beta glucose and alpha glucose. Alpha glucose has the OH group above (in a ring structure)  carbon 1 while the alpha glucose has the OH group below on carbon 1. These two forms of glucose can combine to form other carbohydrates. A classical example of this combination is the combination of two alpha glucose to form maltose. This has an alpha (1-4) glycosidic link as as the bond is formed between carbon 1 and carbon 4 of the glucose molecules.

Two other disaccharide sugars are lactose and sucrose. Lactose is formed from glucose and galactose while sucrose is formed from glucose and fructose. I would really like to show you some structures but as i said i haven’t quite figured this out as yet. But don’t worry i shall not fail you, by next week I should fully know my way around.

Another interesting disaccharide is cellobiose. I want you to go and research the structure of that.( As a matter of fact research the structure of all). That one is my favorite. There is something quite special about it!

Okay peeps, i am sorry but I have to run off now. The “juice” I am taken to get this vial virus outta me is kicking in, so I must prepare for the war.

Until then. Peace out. Love,peace and chicken grease!

Carbohydrates 1

Hey guys,

so the saga continues. This week we got to look at carbohydrates. Everybody knows that the first thing that come to anybody’s mind when they hear about carbohydrates is oh nooo, i am gonna get fatter! People that is not all that is stands for, so it would be a pretty good idea not to run full speed from it at all times. Carbohydrates are hydrates of carbon. Let me break that down further.Carbohydrates consist of hydrogen and carbon more specifically in the following ratio (CH2O)n. So if n=2 then the carbohydrate will be C2H4O4. They even have different functions such as storage and structural support.

So down to the nitty gritty of the matter, does it really make me fat? Well…. I don’t know, this is not a nutrition class i am taking, its a biochemistry class, but i can tell you that if you eat to much, you would have excess energy which the body will store. So please slow down on the amount of carbs. Anyway moving on,  a classical example of a carbohydrate is glucose, which I am sure everyone knows by now, but if you don’t i have attached a glucose song from ‘mhoowen’ compliments of you tube. So take a look and see how much you learn.


Carbohydrates can be separated into ketose and aldehydes. An aldehyde has the functional group  HCO while and ketose has the functional group CO. Our friend glucose is an aldehyde.

If you take a look at the structure of glucose in the song, you will see that its can either be a ring or linear structure. That’s the amazing thing about carbohydrates, some can form rings, or bond to each other to form disaccharides or polysaccharides by way of glycosidic bond. Let me break down those terms. A monosaccharide is a simple sugar with multiple OH bond, but a disaccharide is when two monosaccharides join together by a glycosidic bond.

So I know that’s a lot to digest. So I am gonna sign out now. Leave you to digest!

Peace, love and chicken grease people

“Glucose Song.” [n.d.]. Video clip. Accessed February 09, 2013.


My first biochem experiance

Well what can i say about my first biochem experience? First thing first is that i have never liked biology so i didn’t expect to even like this course! Hey, i am being honest with you, the first impression you got when you came into UWI about biochemistry was “AHHHH RUNNNNN,” OR ” YO GONNA DO BIOCHEM HA GOOD LUCK WITH THAT” so you could understand my thoughts about the subject instantly. However from last year i have new found infatuation ( I don’t wanna go too far out on the limb and say love ) for biology, amazing eh! I actually started to like biology for the first time in my entire life. So i said well hey lets give this biochem a shoot and see what it has to offer. I mean how bad can it be right?
Well first thing first is that there is a test every week and the tutorials are like mini test anyway, and don’t let me get started about the content that we have to cover but hey i am liking it so far. I like that the test keeps us constantly on our toes. I like that in the tutorials we actually interact with each other instead of a tutor begging for people to come up on the board. I love learning about the world around me and even better what is going on inside me. Never know it might save my life someday!
So I am looking forward to this course now and I want to see what it has in store for me, hey you never know i might actually love it when i am finish! HEH we will see!
Peace, love and chicken grease peeps
( By the way I learned there is something such as empty calories. You know food that contain a lot of calories but have no nutritional value whatsoever and here i thought my chocolate cake and Oreo ice cream was my friend! :()