DNA to RNA to a Protein

DNA replication is the molecular mechanism of inheritance. When a cell divides, forming new cells, a complete set of genetic instructions is generated for each new cell. And when an organism reproduces, genetic instructions pass from one generation to the next.

DNA replication-process of copying DNA molecules Semi conservative replication-parental strands of DNA separate, serve as templates, and produce DNA molecules that have one strand of parental DNA and one strand of new DNA. During DNA replication, the two strands of the original parent DNA molecule, shown in blue, each serve as a template for making a new strand, shown in yellow. Replication results in two daughter DNA molecules, each consisting of one original strand and one new strand.

What role to Enzymes play in replication? Unwinding=DNA helicase (enzyme) is responsible for unwinding and unzipping the double helix.

What role to Enzymes play in replication? Continued… Base Pairing=The enzyme DNA polymerase catalyzes the addition of appropriate nucleotides to the new DNA strand.

What role to Enzymes play in replication? Continued… Joining= in eukaryotic DNA there are many areas along the chromosome where replication begins. When the RNA primer has been replaced, the DNA LIGASE links the 2 sections together.

*The answer is RNA (ribonucleic acid) A gene provides the information for making a specific protein. DNA, RNA, Protein One Gene, One Polypeptide Information Flow: DNA to RNA to Protein So what is the connection between these genes and the polypeptide cells? *The answer is RNA (ribonucleic acid)

RNA RNA Sugar is ribose Contains a nitrogenous base called URACIL (U) instead of thymine of DNA RNA typically forms a single, sometimes twisted strand, not a double helix like DNA

Transcription Several RNA molecules play a part in the intermediate steps from gene to protein. In the first step, DNA’s nucleotide sequence is converted to form a single-stranded RNA molecule in a process called TRANSCRIPTION.

Codon A three base code in DNA or mRNA Each of the three bases of a codon in the DNA is transcribed in to the mRNA code. Figure 14 on page 338. We will practice using it tomorrow

Translation The next step , however, requires changing languages. Genetic TRANSLATION converts nucleic acid language into amino acid language.

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