DNA and RNA Notes

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DNA and RNA Notes
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DNA and RNA WHY?

• DNA and RNA are required to make proteins.
• DNA stores information like books in a library,
  information a cell needs to function, grow, and
  divide. Proteins carry out most of the work in a
  cell and make up the structures of a cell.
• Proteins are large molecules made of chains of
  amino acids.
• DNA is a double-stranded spiral, much like a
  twisted ladder. It is made of four different
  nucleotide subunits adenine (A), thymine (T),
  cytosine (C), and guanine (G). The "rungs" of the
  ladder are formed by nucleotide pairs. Adenine
  pairs with thymine cytocine pairs with guanine.
• The order of the bases in a strand of DNA forms
  the code for making proteins.
• A set of three bases, or codon, codes for one
  specific amino acid.

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Mitosis

• Before a cell can divide, all of its DNA must be
  copied in a process called replication.
• The DNA separates into two strands.
• Nucleotides in the area around the DNA match up
  with the strands. A matches with T, and C matches
  with G.
• Once complete, there are two identical DNA
  molecules, each with one strand of old DNA and
  one strand of new DNA. The old strand was a
  template for the new strand.

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Protein Synthesis

• DNA just carries the information to make
  proteins. It does not make proteins directly.
  RNA, or ribonucleic acid, is involved in making
  proteins.
• Transcription is the process of transferring
  information from DNA to RNA.
• DNA is used as a template, this time to make a
  complementary strand of RNA. Only a gene is
  transcribed, not the whole DNA molecule.
• NA bases match to DNA bases. Adenine matches to
  uracil cytocine matches to guanine. Uracil takes
  the place of thymine in RNA molecules.
• Once the gene is transcribed, the mRNA is
  released.

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Protien Synthesis cont.

• Protein synthesis begins with the stored genetic
  information of a DNA molecule.
• Only on e side of the DNA is used.
• A single-strand of RNA forms, one subunit at a
  time, and transcribes(copies) the genetic
  information from the DNA
• The new strand is an RNA molecule. Note that
  there is one difference in the subunits RNA
  contains uracil instead of thymine.
• The DNA zips closed and remains in the nucleus.

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Protein Synthesis

• The messenger RNA (MRNA) will then leave the
  nucleus and travel to a ribosome to build the
  protein molecule.
• The messenger RNA contains information in sets of
  three subunits. Each set of three is the code
  for a particular amino acid.
• Small molecules of transfer RNA will carry the
  proper amino acids in, linking them together.
• The chain of amino acids, when long enough is
  called a protein.