DNA transcription and translation McGraw Hill

00:07:18
https://www.youtube.com/watch?v=8_f-8ISZ164

概要

TLDRThe video explains the essential processes of digestion and protein synthesis in the body. It begins with the breakdown of food into nutrients through chemical digestion, emphasizing the role of proteins and enzymes. The video then delves into the genetic basis of protein production, detailing how DNA contains genes that encode for proteins. It describes the processes of transcription and translation, where messenger RNA is synthesized from DNA and then translated into polypeptides. Key components such as RNA polymerase, spliceosomes, and ribosomes are highlighted, along with the importance of post-translational modifications. The video concludes by underscoring the critical role of proteins in various physiological functions, including digestion.

収穫

  • 🍽️ Digestion breaks down food into usable nutrients.
  • 🧬 DNA contains the instructions for protein production.
  • ✍️ Transcription occurs in the nucleus, creating messenger RNA.
  • 🔄 Translation occurs in the cytoplasm, synthesizing polypeptides.
  • 🧪 RNA polymerase is crucial for synthesizing RNA from DNA.
  • ✂️ Introns are removed from RNA during splicing.
  • 🔗 Codons are three-letter codes that specify amino acids.
  • 🔄 tRNA brings amino acids to the ribosome during translation.
  • 🏭 Proteins undergo modifications in organelles before functioning.
  • 💡 Proteins are essential for physiological functions like digestion.

タイムライン

  • 00:00:00 - 00:07:18

    The human body requires a variety of nutrients from our diet, which undergoes chemical digestion to break down food into usable nutrients. The instructions for manufacturing proteins are found in DNA, which contains genes made up of nucleotides. Genes have regions that code for RNA, starting with a promoter and ending with a terminator, and regulatory sequences that control gene expression. Gene expression involves transcription and translation, where transcription occurs in the nucleus to create messenger RNA (mRNA) from DNA, followed by translation in the cytoplasm to synthesize polypeptides.

マインドマップ

ビデオQ&A

  • What is the role of DNA in protein synthesis?

    DNA contains genes that provide the instructions for making proteins.

  • What are the two main processes of gene expression?

    The two main processes are transcription and translation.

  • Where does transcription occur in eukaryotic cells?

    Transcription occurs in the nucleus.

  • What is the function of RNA polymerase?

    RNA polymerase synthesizes messenger RNA from the DNA template during transcription.

  • What are exons and introns?

    Exons are coding regions of RNA, while introns are non-coding sections that are removed during RNA processing.

  • What is the purpose of translation?

    The purpose of translation is to produce polypeptides from messenger RNA.

  • What happens to the polypeptide after translation?

    The polypeptide may undergo modifications in organelles before it is functional.

  • How are proteins secreted in the body?

    Proteins are translated in the endoplasmic reticulum, modified in the Golgi apparatus, and secreted via vesicles.

  • What is a codon?

    A codon is a three-letter code in messenger RNA that corresponds to a specific amino acid.

  • What is the role of transfer RNA (tRNA)?

    tRNA brings specific amino acids to the ribosome during translation based on the codon-anticodon pairing.

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オートスクロール:
  • 00:00:00
    in order for our bodies to function we
  • 00:00:02
    need to supply them with a variety of
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    nutrients we get from our diet
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    our bodies cannot use the food as it is
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    when it enters our digestive system the
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    process of chemical digestion uses
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    different proteins and enzymes to break
  • 00:00:18
    down the food particles into usable
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    nutrients our cells can absorb
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    and where are the instructions to
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    manufacture these and all the different
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    types of proteins we need to stay alive
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    the instructions to make proteins are
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    contained in our DNA DNA contains genes
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    a gene is a continuous string of
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    nucleotides containing a region that
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    codes for an RNA molecule this region
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    begins with a promoter and ends in a
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    terminator genes also contain regulatory
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    sequences that can be found near the
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    promoter or at a more distant location
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    for some genes the encoded RNA is used
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    to synthesize a protein in a process
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    called gene expression for these genes
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    expression can be divided into two
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    processes transcription and translation
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    in eukaryotic cells transcription occurs
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    in the nucleus where DNA is used as a
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    template to make messenger RNA then in
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    translation which occurs in the
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    cytoplasm of the cell
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    the information contained in the
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    messenger RNA is used to make a
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    polypeptide
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    during transcription the DNA in the gene
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    is used as a template to make a
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    messenger RNA strand with the help of
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    the enzyme RNA polymerase this process
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    occurs in three stages initiation
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    elongation and termination during
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    initiation the promoter region of the
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    gene functions as a recognition site for
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    RNA polymerase to bind this is where the
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    majority of gene expression is
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    controlled by either permitting or
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    blocking access to this site by the RNA
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    polymerase binding causes the DNA double
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    helix to unwind and open then during
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    elongation the RNA polymerase slides
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    along the template DNA strand as the
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    complementary bases pair up the RNA
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    polymerase links nucleotides to the
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    three prime end of the growing RNA
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    molecule
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    once the RNA polymerase reaches the
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    terminator portion of the gene the
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    messenger RNA transcript is complete and
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    the RNA polymerase the DNA strand and
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    the messenger RNA transcript dissociate
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    from each other
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    the strand of messenger RNA that is made
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    during transcription includes regions
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    called
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    exons that code for a protein and
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    non-coding sections called introns in
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    order for the messenger RNA to be used
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    in translation the non-coding introns
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    need to be removed and modifications
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    such as a five prime cap and a 3 prime
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    poly a tail are added
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    this process is called introns splicing
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    and is performed by a complex made up of
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    proteins and RNA called a spliceosome
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    this complex removes the intron segments
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    and joins the adjacent exons to produce
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    a mature messenger RNA strand that can
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    leave the nucleus through a nuclear pore
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    and enter the cytoplasm to begin
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    translation
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    how is the information in the mature
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    messenger RNA strand translated into a
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    protein the nitrogenous bases are
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    grouped into three letter codes called
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    codons
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    the genetic code includes 64 codons most
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    codons code for specific amino acids
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    there are four special codons one that
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    codes for start and three that code for
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    stop
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    translation begins with the messenger
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    RNA strand binding to the small
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    ribosomal subunit upstream of the start
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    codon each amino acid is brought to the
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    ribosome by a specific transfer RNA
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    molecule the type of amino acid is
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    determined by the anticodon sequence of
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    the transfer RNA
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    complementary base pairing occurs
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    between the codon of the messenger RNA
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    and the anticodon of the transfer RNA
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    after the initiator transfer RNA
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    molecule binds to the start codon the
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    large ribosomal subunit binds to form
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    the translation complex and initiation
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    is complete
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    in the large ribosomal subunit there are
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    three distinct regions called the e P
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    and a sites
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    during elongation individual amino acids
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    are brought to the messenger RNA strand
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    by a transfer RNA molecule through
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    complementary base pairing of the codons
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    and anticodons each Eddie codon of a
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    transfer RNA molecule corresponds to a
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    particular amino acid
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    a charged transfer RNA molecule binds to
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    the a site and a peptide bond forms
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    between its amino acid and the one
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    attached to the transfer RNA molecule at
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    the P site
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    the complex slides down one codon to the
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    right where the now uncharged transfer
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    RNA molecule exits from the e site and
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    the a site is open to accept the next
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    transfer RNA molecule
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    elongation will continue until a stop
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    codon is reached
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    a release factor binds to the a site at
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    a stop codon and the polypeptide is
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    released from the transfer RNA in the P
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    site the entire complex dissociates and
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    can reassemble to begin the process
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    again at initiation the purpose of
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    translation is to produce polypeptides
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    quickly and accurately
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    after dissociation the polypeptide may
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    need to be modified before it is ready
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    to function
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    modifications take place in different
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    organelles for different proteins
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    in order for a digestive enzyme to be
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    secreted into the stomach or intestines
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    the polypeptide is translated into the
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    endoplasmic reticulum
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    modified as it passes through the Golgi
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    then secreted using a vesicle through
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    the plasma membrane of the cell into the
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    lumen of the digestive tract
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    proteins are needed for most
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    physiological functions of the body to
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    occur properly such as breaking down
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    food particles in digestion and the
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    processes of transcription and
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    translation make the production of
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    proteins possible
タグ
  • digestion
  • protein synthesis
  • DNA
  • transcription
  • translation
  • RNA polymerase
  • exons
  • introns
  • codons
  • tRNA