DNA,%20RNA,%20and%20PROTEIN%20SYNTHESIS

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DNA, RNA, and PROTEIN SYNTHESIS
DNA is a molecule that carries the instructions
for how to make an organism
DNA, genome, instructions, blueprint,
chromosomes, genes All MEAN DNA!!!! THEY ALL
HAVE TO DO WITH DNA
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• DNA is organized into bundles called CHROMOSOMES.
  Humans have 46 chromosomes
• CHROMOSOMES have segments on them that code for
  certain qualities (eye color, hair color)
• The segments or areas are called GENES and they
  code for all of an organisms TRAITS or
  characteristics

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• Gametes sperm/egg

• DNA is found in, and cannot leave the nucleus
  (too big).

• The types of cells that carry information from
  parents to offspring are called gametes.
• Gametes are sex cells, sperm and egg.
• Humans and their cells have 46 chromosomes.
• 23 come from mom (egg), 23 come from dad (sperm).

• Since it has such important information it is
  guarded in the nucleus of cells.
• DNA carries information from parents to offspring
  (kids)

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• DNA (DeoxyRiboNucleic Acid) is made up of
  nucleotides that repeat.
• Each nucleotide is made of 3 parts

1.Nitrogen base
2.Deoxyribose sugar group Dewithout Oxy
Oxygen Ribosesugar
3.Phosphate group
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There are 4 nitrogen basesAdenine (A), Cytosine
(C), Thymine (T), and Guanine (G)The sequence
of nitrogenous bases determines the traits that
will appear. The sequence of codons (3 letter
codes)
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DeoxyribonucleicAcid (DNA) the Double Helix
The sugar and phosphate groups make up the
outside part of the ladder. The base pairs make
up the inside steps of the ladder.
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Watson Crick were the first to successfully
show the structure of DNA. (Double Helix)
According to Chargaffs rule A pairs to TC
pairs to G The bases are found in a 11 ratio
adenine bonds with thymine
guanine bonds with cytosine
The two halves of the DNA strand are called
complementary because they pair together
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Reasons why cells divide
Mitosis/Cell Division

• The cell becomes too big.
• The larger a cell becomes, the more demands the
  cell places on its DNA
• Also, a larger cell has more trouble keeping up
  with the needs of the cell
• Cells will continually divide during the growth
  of an organism.

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The process by which cells divide

• Before a cell divides it must make an exact
  copy or replica of its DNA.
• The copy or replica of DNA is made during the
  S-Phase of Interphse.
• After Interphase is complete the cell can divide
  by Mitosis.
• Cell Division or Mitosis allows organisms to grow
  larger while cells remain small

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Replication First the DNA unzips
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Next new nucleotides are added to each side until
2 identical strands are made (remember A to T and
C to G)
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Replication / Mitosis
Mitosis results in 2 identical daughter
cells Each has all 46 chromosomes An exact copy
of the original
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Protein Synthesis

• 1. DNA is the code the instructions for how
  to make PROTEINS, the main structures of the
  body.
• 2. DNA is in the nucleus of the cell, but
  PROTEINS are made in the cytoplasm by RIBOSOMES.
• Remember, DNA cannot leave the nucleus.
• We need a way to get the DNA out of the nucleus
  to the ribosomes. Protein synthesis happens in 2
  steps.

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Protein Synthesis Step 1 Transcription

• The DNA strand in the nucleus separates.
• In order to get BIG DNA out of the nucleus we
  must re-write it as a messenger (RNA).
• This RNA acts as a messenger (mRNA) that carries
  the instructions out of the nucleus to the
  ribosome
• When the genetic code (DNA) is copied/re-written
  to messenger RNA, mRNA this is called
  transcription.

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Rna (ribo-nucleic-acid)

• RNA has Ribose as its sugar instead of
  Deoxyribose
• It is Single Stranded, meaning that it is only
  half of the ladder (double helix)
• RNA has Uracil as a base instead of Thymine
• Guanine Cytosine
• Adenine Uracil (no T, Thymine in RNA)

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Step 2 Translation
We translate 3 letter codons into an amino acid
chain.

1. mRNA attaches to a RIBOSOME

• Every 3 letter group on a strand of mRNA is a
  CODON which codes for an AMINO ACID
• - amino acids are the building blocks of
  proteins (20 of them 9 are essential)

AMINO ACIDS
3. The RIBOSOME reads the mRNA, then transfer
RNA (tRNA) brings the correct AMINO ACID to form
the protein chain
3 letter CODONS on mRNA tell what the AMINO ACID
will be
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What 2 amino acids do these CODONS code for?
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The Central Dogma
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Mitosis vs. Meiosis
Meiosis results in 4 genetically Different
haploid cells. Haploid means half The Gametes
(sex cells) have ½ the info
Mitosis results in 2 identical daughter
cells Each has all 46 chromosomes
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NameDate Biologyclass pd.Write about DNA.
What is DNA?What is the structure and parts of
DNA?How is DNA used to make proteins in protein
synthesis