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Bio Chp. 13 N
Biology chapter 13
Question | Answer |
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3. List 4 differences between RNA and DNA. | the three main differences between RNA and DNA are DNA is the master plan while RNA acts as a blueprint, DNA remains in the safety of the nucleus while RNA goes to the ribosomes, and RNA has one strand while DNA has two. |
4. State the role of RNA; describe the function of the 3 different types of RNA. | form ribosomes. Messenger mRNA is translated into protein by the joint action of transfer tRNA and the ribosome, which is composed of many proteins and two major ribosomal rRNA molecules.Ribosomal rRNAassociates with a set of proteins to form ribosomes. |
5. Describe the steps involved in the process of transcription, and state when and where it occurs. | part of DNA strand codes for a needed protein gene briefly breaks.RNA polymerase is the enzyme that separates the strands.mRNA assembles a complementary sequence,Thymine swapped Uracil. mRNA strand goes to cytoplasm and attaches to a ribosome. |
6. Given a sequence of DNA, be able to determine the complimentary mRNA sequence and corresponding amino acid sequence. | CGTACATG= GCUTGTUC mRNA= Aedenisine changes to a (U) |
7. Describe the “genetic code”. Use the term codon in your description. | The genome of an organism is inscribed in DNA, or some viruses RNA.The portion of the genome that codes for a protein or RNA is referred as gene.Those genes that code for proteins are composed of tri-nucleotide units codons,each code for single amino acid |
8.State the location of translation, and describe the steps involved in the process. • Be sure to include the relationship between the mRNA and tRNA molecules in the making of polypeptides; use the terms ribosome, codon, anticodon and amino acid. | At ribosome correct tRNAs line up to match the complementary codons on mRNACodons on the mRNA match with anticodons on the tRNA sequence of amino acids is assembled into a polypeptide chain for protein Polypeptide chain of amino acids linked peptide bonds |
9. State the “central dogma” of molecular biology. | the coded genetic information hard-wired into DNA is transcribed into individual transportable cassettes, composed of messenger RNA (mRNA); each mRNA cassette contains the program for synthesis of a particular protein |
10. Define the term mutation, and state the different types of mutations. | A mutation is simply a change in your genes or DNA sequence. The types of mutations in biology are: substitution, insertion, deletion, and frame-shift. Contrary to popular belief, mutations are often harmless. |
5. state when and where Transcription occurs | Occurs in the Nucleus and happens before meiosis. S/ synthesis. |
Gene | a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring. |
RNA | Its principal role is to act as a messenger carrying instructions from DNA for controlling the synthesis of proteins, although in some viruses RNA rather than DNA carries the genetic information. |
Transcription | Transcription is the process by which the information in a strand of DNA is copied into a new molecule of messenger RNA (mRNA). |
Polypeptide | A polymer of amino acids joined together by peptide bonds |
Codon | a sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA molecule. |
Anticodon | a sequence of three nucleotides forming a unit of genetic code in a transfer RNA molecule, corresponding to a complementary codon in messenger RNA. |
Translation | Translation is a step in protein biosynthesis wherein the genetic code carried by mRNA is decoded to produce the specific sequence of amino acids in a polypeptide chain. The process follows transcription in which the DNA sequence is copied into an mRNA. |
Gene expression | Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product. |
Mutation | A Mutation occurs when a DNA gene is damaged or changed in such a way as to alter the genetic message carried by that gene. |
Mutagen | s a physical or chemical agent that changes the genetic material, usually DNA, of an organism and thus increases the frequency of mutations above the natural background level. |
Cell differentiation | The process by which a cell becomes specialized in order to perform a specific function, as in the case of a liver cell, a blood cell, or a neuron. |
11. Explain how a mutation in the sequence of DNA (a gene) leads to a change in the sequence of amino acids in a protein. | A single substitution mutation has changed the base sequence in the DNA. The base sequence on the mRNA produced by the DNA is altered. As a result, a codon on the mRNA is altered. A different amino acid is inserted into the protein chain. |
12. List 3 factors that can cause mutations. | UV light RADIATION CHEMICALS TOBACCO |
13. Explain why not all mutations are bad. | No.Many go unnoticed – don’t make a difference.Some are good – increase variety.We notice the negative changes … as they have a negative effect on ourwellbeing. |
14. Explain how gene expression results in cell differentiation, and state the importance of cell differentiation. |