Eukaryotic cells possess 80s ribosomes. What does the “s” unit of measurement stand for?
A. Schwann
B. Szilard
C. Schrödinger
D. Svedberg
E. Sarutobi
Select the correct multiple answer using ONE of the keys A, B, C, D or E as follows:
A. 1, 2 and 3 are correct
B. 1 and 3 are correct
C. 2 and 4 are correct
D. only 4 is correct
E. all are correct
What is/are the function(s) of carbohydrates?
1. Energy production
2. Energy storage
3. Precursor molecules
4. Basic genetic material
Holla hommes! Welcome back! On this post we’re talking about Nucleotides and Nucleic Acids…which should be hella obvious from the title, or not, but what-evz! Now you know. So what is a nucleotide? Well that’s pretty simple. A nucleotide is an organic molecule that is a subunit of the nucleic acids DNA and RNA. What are they made up of you may ask? And to this question I shall answer that it is a nucleoside + a phosphate. And now you want to know what a nucleoside is made up of right? Of course you do. A nucleoside made up of a nitrogenous base + five-carbon sugar therefore a nucleotide is a nitrogenous base + five-carbon sugar + phosphate.
Okay, so how about we get all up in this nucleotide and see what’s going on with the sugar! By the way, the sugar is the main characteristic of the DNA and RNA. Deoxyribonucleic acid who goes by the street name DNA is made up of deoxyribose and Ribonucleic acid whose street name is RNA (as you may have guessed) is made up of ribose sugar. (The ‘de’ in deoxyribose indicates the lack of oxygen on the second carbon in the ribose sugar.)
Our homme DNA
DNA – The mysterious double helix, self-replicating material that makes up our chromosomes and is the carrier for our genetic information. As mentioned before DNA is made up of a five-carbon sugar, a nitrogenous base, and a phosphate. Lets talk about the nitrogenous bases in DNA. There are two categories of nitrogenous bases, single ring and double ring. The single ring bases are known as pyrimidines, which consist of Cytosine (C), Thymine (T) and Uracil (in RNA) and double ring bases are purine, which consist of Adenine (A) and Guanine (G). In DNA a purine always pairs with a pyrimidine by means of a hydrogen bond, which is strong enough to hold them together, but also allows them to be separated when necessary. This bonding creates the ladder seen in the double helix formation. Adenine is paired with Thymine and Cytosine is paired with Guanine. The backbone, which is seen on the outskirts of the double helix, is made of sugar-phosphate pairs. The backbones run from 3’ (3 prime) – the sugar end to 5’ (5 prime) – the phosphate end and are anti-parallel to each other. Therefore one side is 3’ – 5’ and the other side is 5’ to 3’.
Namingggg! (The simplest part)
For Nucleosides:
– For purine nucleosides would simply change the ending to “-sine”: Guanosine & Adenosine
– For pyrimidine nucleosides you would change the ending to “-dine”: Thymidine, Uridine, Cytidine,
For Nucleotides:
– You would begin with the nucleoside name above and then add “mono-”, “di-”, or “triphosphate” according to the number of phosphates present (Mono=1, Di=2, Tri=3): Adenosine Monophosphate, Cytidine Triphosphate, Deoxythymidine Diphosphate.
I know you’re like, seriously though, like what’s the big deal with nucleotides?
Welllllll I’ll tell you what the big deal is! First of all, nucleotides are the building blocks of DNA and RNA. Meaning with out them we’d be nothing, zip, zilch, zero, and nada homie! They can be compared to amino acids in their role in proteins. They are responsible for selectively binding to a protein and regulating its activities. In other words they are allosteric effectors. They serve as an energy currency in cellular metabolism and they make up the structures of many enzyme cofactors?
And now you’re all like, what about nucleic acids!!?
Gosh chill, I was getting there. Well most importantly, DNA has the information needed to create fuctional proteins and RNAs. They also have promoters that assist in the regulation of gene expression. rRNAs or Ribosomal RNAs help to make up ribosomes and they help with the creation of proteins. mRNAs (Messenger RNAs) are like FedEx for genetic information. They transport genetic information from the gene to the ribosome. tRNAs decode information in mRNAs into an amino acid sequence and some RNAs can increase the rate of biochemical reactions
Most Famous Nucleotide!! – ATP!!!
Real name, Adenosine Triphosphate isanucleotide containing adenine, ribose, and a triphosphate group.ATP is often wrongly referred to as an energy-storage molecule, however a more accurate term would be an energy carrier or energy transfer agent. ATP diffuses though the cell to make energy so that the cell can perform other work such as ion transport, cell movement and biosynthetic reaction. ATP’s chemical potential energy is made available when one or two of its phosphate groups are relocated to another molecule. This course of action can be denoted by the hydrolysis of ATP to ADP.
Forms of Nucleic Acids
B form – This is the most common conformation for DNA.
A form – This is common for RNA and is favored in conditions of low water. Contains deeper minor groove and shallow major groove.
Z form – Contains narrow, deep minor groove and the major groove is hardly existent. This can form for some DNA sequences and requires alternating syn and anti base configurations. It is known as being left handed, meaning that is coil in the left direction. Z form also contains high salt/charge neutralization.
And finally: Stability of Nucleic Acids
Nucleic acids contain hydrogen bonding but it is not usually a factor the stability of nucleic acids however it contributes to the double helix in DNA and RNA secondary structure. What does contribute to the nucleic acid stability is the hydrophobic interaction between base pairs. It is favorable for the hydrophobic bases to exclude waters and stack on top of each and this stacking is expand in double-stranded DNA.
Thanks so much for reading and I hope you found it informative and helpful.
Chao for now!
What rhymes with lipid? Well, that doesn’t matter right now, the better question is, what is a lipid? Anyone? OKAY OKAY, I’ll tell you. Basically it’s a group of organic compounds comprising waxes, oils or fats. Useful fact about oils is that they contain unsaturated hydrocarbon chains c=c bonds however, fats contain the opposite which are saturated hydrocarbon chains… and because of this, fats are solids and oils are liquids at room temperature. Waxes are just waxes (fatty acid = long chain alcohol) .
Wait, what’s that? Fatty Acids?
A fatty acid is not what’s behind Beyonce, but it is really a carboxylic acid consisting of a hydrocarbon chain and a terminal carboxyl group usually found as esters in fats and oils. They are used by the body as a source of energy, provide insulation from the cold and protects vital organs.
Why fat?
Well; it helps in the formation of cell membranes, provides the steroid nucleus with hormones, carries fat soluble vitamins, adds flavour to foods.
Straight Talk.
* Saturated fats have no double bonds, they are long straight chains. They contribute however to cardiovascular disease, the build-up of plaque in the arteries and even arteriosclerosis.
* Unsaturated fats have double bonds present. (‘cis’ form double bond, forming a kink) This prevents the fat molecules from packing tightly (healthier fat)
* The double bonds in monosaturated fatty acids occur between C9 and C10 and in polysaturated fatty acids more double bonds are found at C12 and C15.
* As the number of carbon atoms increase in a fatty acid, the melting point also increases… however the solubility in water decreases.
* Most fats are comprised of a mixture of saturated, monounsaturated and polyunsaturated fatty acids.
* There are both essential and non-essential fatty acids.
* Trans Fats and saturated fats both put your hearts health at risk!
* Essential fatty acids! OMEGA – 6 – LINOLEIC acid and OMEGA-3 ALPHA- LINOLENIC acid.
REFERENCES
http://telstar.ote.cmu.edu/biology/MembranePage/images/representation.jpg http://myhealthyfriends.blogspot.com/2013/08/packaged-foods-have-much-more-trans-fat.html http://courses.washington.edu/conj/membrane/fattyacids.htm
What the heck are enzymes?
You don’t know what enzymes are? Really?! Ok that’s fine. An enzyme is simply a biological catalyst. It speeds up a biological reaction with out being used or changed and it is specific, meaning each enzyme only works on a specific substrate. For example lipase hydrolyses lipids and only lipids. (How do enzymes speed up reactions though? ) OMG glad you asked! They just create a different pathway that has lower activation energy than the original pathway.
Most enzymes are proteins, some are RNA molecules known as ribozymes (they satisfy mostly all of the enzymatic criteria eg. they are substrate specific, they speed up the reaction rate, and they remain unchanged after the reaction. Some antibodies have catalytic properties and these are called abzymes.
What’s the big deal about enzymes?
Without enzymes life is literally impossible! Enzymes allow for respiration to occur. Which means, no enzymes à no energy à no life. Thank goodness for enzymes right? Yeah… trust me I know.
According to Ask.com, in the human body approximately 2700 enzymes can be found. These enzymes are separated into three major groups, which are: metabolic enzymes, food enzymes and digestive enzymes. Their location in the body depends on their function. Enzymes can be found in the mouth in saliva, in the stomach and everywhere else in the body. Without enzymes we are nothing!
This is an energy profile diagram.
This diagram shows exactly how enzymes speed up the reaction to produce product.
But what is activation energy? Activation energy is the minimum energy needed for a reactant to react.
How do enzymes get their name?
Um… their parents obviously name them at birth just like everyone else! No, just kidding. Enzymes are either named based on the substrate they react on, the action they perform, they end in ‘ase’ or they just have some random name that has nothing to do with them. Because names were getting out of hand, our homies at The International Union of Biochemistry and Molecular Biology, IUBMB for short, decided to come up with a naming system. They divided the enzymes into 6 classes. In each class is a sub class and in each subclass there is a sub-subclass. Each is numbered and therefore a series of 4 numbers specifies a specific enzyme (this is called the Enzyme Commission [E.C.] number.
The 6 major classes are:
Holoenzyme?? Hol up.. holo what??
Omg chillllll! Its simple! A holoenzyme is just a biochemical compound that is a combination of an enzyme and a coenzyme. And before you go a-wall! A coenzyme is just a substance that is necessary for an enzyme to function.
Inorganic Catalyst v.s Biological Catalyst
Well incase you didn’t know, biological catalyst are THEE (emphasis on thee) fastest by far when compared to inorganic ones. Biological catalysts are also the most efficient. For example: during the Haber process, which makes ammonia, the temperature needed is 450 degree Celsius, at 1000 atm! What? Amylase breaks down starch to maltose in my mouth and at less than 100 degrees Celsius! And unless you’re a fire-breathing dragon it does the same for you!
So whenever you’re feeling on top of the world, and feel that you can take on a lion, tiger or bear… give enzymes a quick shout out, because with them my good friend… you are without life.
Here’s some pickup lines! Use them wisely.
In that order!
Chao for now!
mollycools 