DNA Structure
DNA is the shape of a twisted ladder called a double-helix. The double helix contains two polynucleotide (composed of many nucleotide components) strands looped around each other. The two strands are anti-parallel, meaning they both go in opposite directions.
It has a backbone of phosphate groups and sugar (deoxyribose). Inside the double helix which are the steps of the twisted ladder are purine and pyrimidine bases which are hold by hydrogen bonds. The name of the bases are Adenine, Guanine, Thymine, and Cytosine. Purine bases always pairs with pyrimidine bases.
Adenine always pairs with Thymine (vice versa) Guanine always pairs with Cytosine (vice versa) DNA are made up of nucleotides Nucleotides are made up of a
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DNA Replication &
protein synthesis
DNA Replication:
DNA Replication is a semi-conservative process of producing two identical replicas from one original DNA molecule. DNA Replication is referred to as semi-conservative, because one half of the DNA is the old template and the other is new DNA. DNA Replication is important, because during for cell division, it needs to duplicate an original copy of the DNA for the new cell to have information and to carry out its growth and development. That is why DNA Replication is important for your body, because it keeps it healthy. |
These are the steps of the process of DNA Replication. These enzymes help with DNA replication.
1. Helicase: Helicase breaks down and unzips the DNA and breaks down hydrogen bonds which holds the nitrogen bases.
2. RNA Primase: RNA Primase adds a short segment of RNA, and the RNA Primer sends signal to begin replication.
3. DNA Polymerase: DNA Polymerase adds new DNA nucleotides to the strand along both sides of DNA. DNA Polymerase builds the daughter strand by pairing new nucleotides to their complementary bases on the parent (original) strand. In addition, It removes the RNA primers before lagging strands are bound together.
4. Leading Daughter Strand (left strand of DNA): The leading daughter strand is the parent strand of DNA, and DNA Polymerase replicates continuously.
5. Lagging Daughter Strand (right strand of DNA): The lagging daughter strand is replicated in small pieces called Okazaki fragments that are later bound together by an enzyme ligase into one long strand.
1. Helicase: Helicase breaks down and unzips the DNA and breaks down hydrogen bonds which holds the nitrogen bases.
2. RNA Primase: RNA Primase adds a short segment of RNA, and the RNA Primer sends signal to begin replication.
3. DNA Polymerase: DNA Polymerase adds new DNA nucleotides to the strand along both sides of DNA. DNA Polymerase builds the daughter strand by pairing new nucleotides to their complementary bases on the parent (original) strand. In addition, It removes the RNA primers before lagging strands are bound together.
4. Leading Daughter Strand (left strand of DNA): The leading daughter strand is the parent strand of DNA, and DNA Polymerase replicates continuously.
5. Lagging Daughter Strand (right strand of DNA): The lagging daughter strand is replicated in small pieces called Okazaki fragments that are later bound together by an enzyme ligase into one long strand.
RNA Structure
RNA is very similar to DNA. They are both made up of nucleotides and genes. However, there are big differences that makes RNA different from DNA. Their structure of RNA is different and nucleotide components.
Structure of RNA: RNA is made up of a phosphate, a sugar (ribose), and bases (A,U,C,G). Instead of RNA having a deoxyribose sugar like in DNA; it has ribose sugar. Not to mention, the bases are slightly different as well. Instead, of RNA having Thymine as a base, it has Uracil as a base. Moreover, instead of Adenine always pairing with Thymine; Adenine pairs with Uracil in RNA. A = U G = C Types of RNA:
RNA is usually located in the nucleus, in the cytoplasm, or ribosomes |
Protein synthesis
Protein synthesis is the building or making of proteins.
*Central Dogma*
DNA --> RNA --> Protein
DNA to RNA is a process called Transcription. Is the 1st step in making proteins and the process of taking DNA and converting into an mRNA strand.
Transcription is the 1st step in making proteins and the process of taking DNA and converting into a messenger RNA (mRNA) strand.
Messenger RNA is a single-stranded RNA molecule that is complementary to one of the DNA strands of a gene. Messenger RNA leaves the cell nucleus and moves to the ribosomes where it directs the synthesis of the protein and makes proteins. The ribosome moves along the mRNA, reads the bases, and uses the genetic code (information to convert a message from DNA and RNA sequences) to translate each codon into its amino acid.
*Central Dogma*
DNA --> RNA --> Protein
DNA to RNA is a process called Transcription. Is the 1st step in making proteins and the process of taking DNA and converting into an mRNA strand.
Transcription is the 1st step in making proteins and the process of taking DNA and converting into a messenger RNA (mRNA) strand.
Messenger RNA is a single-stranded RNA molecule that is complementary to one of the DNA strands of a gene. Messenger RNA leaves the cell nucleus and moves to the ribosomes where it directs the synthesis of the protein and makes proteins. The ribosome moves along the mRNA, reads the bases, and uses the genetic code (information to convert a message from DNA and RNA sequences) to translate each codon into its amino acid.
RNA --> Protein
RNA to Protein is a process called Translation. It is the process in which ribosomes create proteins.
In translations, mRNA is decoded or interpreted by a ribosome to produce a specific amino acid chain (sequence of amino acids) or a polypeptide.
Every 3 bases on mRNA are called codons. Codons are what code specific amino acids. The initiation occurs when ribosome subunits, initiation factors, and tRNA bind the mRNA near the AUG start codon. The 1st codon always starts on AUG. "AUG" always starts the code for codons to code for specific amino acids.
During translation, tRNA binds to the codon at A-site and a peptide bond is formed between the new amino acid and the increasing chain which is on the P-site. The peptide moves one codon position to get ready for another amino acid coming up next.
When the ribosome confronts with one of the three stop codons, it knocks down the ribosome and releases the polypeptide which is on the E-site (exit). At the end of translation is a polypeptide chain which folds and folds to make proteins.
RNA to Protein is a process called Translation. It is the process in which ribosomes create proteins.
In translations, mRNA is decoded or interpreted by a ribosome to produce a specific amino acid chain (sequence of amino acids) or a polypeptide.
Every 3 bases on mRNA are called codons. Codons are what code specific amino acids. The initiation occurs when ribosome subunits, initiation factors, and tRNA bind the mRNA near the AUG start codon. The 1st codon always starts on AUG. "AUG" always starts the code for codons to code for specific amino acids.
During translation, tRNA binds to the codon at A-site and a peptide bond is formed between the new amino acid and the increasing chain which is on the P-site. The peptide moves one codon position to get ready for another amino acid coming up next.
When the ribosome confronts with one of the three stop codons, it knocks down the ribosome and releases the polypeptide which is on the E-site (exit). At the end of translation is a polypeptide chain which folds and folds to make proteins.
This chart up above represents the amino acids which are what the codons code.
{Each of the codons represent an amino acid}
{Each of the codons represent an amino acid}
Documentations:
(Source: Modified from, Mader, S.S. 2010. Biology. Ed. 10. Used for educational purpose.)
http://desertbruchid.net/4_GB1_LearnRes_fa10_f/4_GB1_LearnRes_Web_Ch12.html
"Transcription Quizzes." ProProffs, 2015. Web. 25 March 2015.
http://www.proprofs.com/quiz-school/topic/transcription
Pujari, Saritha. "Major Steps Involved in the Mechanism of DNA Replication - Biology. Your Article Library, 23 March 2015. Web. 27 March 2015.
http://www.yourarticlelibrary.com/biology/major-steps-involved-in-the-mechanism-of-dna-replication-biology/6546/
"What is RNA and What Does It Do?" Science Prof, February 2015. Web. 27 March 2015.
http://www.weebly.com/weebly/main.php#
Mitchell, Herbert. "Wonders of God's Creation." Second Session, 21 September 2002. Web. 27 March 2015.
http://herbmitchell.info/SECONDSESSION.htm
"25.11 Nucleic Acids." Prenhall. Web. 24 March
2015.
http://wps.prenhall.com/wps/media/objects/3313/3393159/blb2511.html
"3.3 DNA Structure." BioNinja. Web.. 23 March 2015.
http://www.ib.bioninja.com.au/standard-level/topic-3-chemicals-of-life/33-dna-structure.html
"Carbon Life." PennState, 2015. Web. 23 March 2015.
https://online.science.psu.edu/biol110_sandbox_8862/node/8949
Kyrk, John. "The Double Helix." kimball, 21 February 2011. Web.
23 March 2015.
(Source: Modified from, Mader, S.S. 2010. Biology. Ed. 10. Used for educational purpose.)
http://desertbruchid.net/4_GB1_LearnRes_fa10_f/4_GB1_LearnRes_Web_Ch12.html
"Transcription Quizzes." ProProffs, 2015. Web. 25 March 2015.
http://www.proprofs.com/quiz-school/topic/transcription
Pujari, Saritha. "Major Steps Involved in the Mechanism of DNA Replication - Biology. Your Article Library, 23 March 2015. Web. 27 March 2015.
http://www.yourarticlelibrary.com/biology/major-steps-involved-in-the-mechanism-of-dna-replication-biology/6546/
"What is RNA and What Does It Do?" Science Prof, February 2015. Web. 27 March 2015.
http://www.weebly.com/weebly/main.php#
Mitchell, Herbert. "Wonders of God's Creation." Second Session, 21 September 2002. Web. 27 March 2015.
http://herbmitchell.info/SECONDSESSION.htm
"25.11 Nucleic Acids." Prenhall. Web. 24 March
2015.
http://wps.prenhall.com/wps/media/objects/3313/3393159/blb2511.html
"3.3 DNA Structure." BioNinja. Web.. 23 March 2015.
http://www.ib.bioninja.com.au/standard-level/topic-3-chemicals-of-life/33-dna-structure.html
"Carbon Life." PennState, 2015. Web. 23 March 2015.
https://online.science.psu.edu/biol110_sandbox_8862/node/8949
Kyrk, John. "The Double Helix." kimball, 21 February 2011. Web.
23 March 2015.