Val his leu thr pro glu glu val his leu thr pro val

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Val His Leu Thr Pro Glu Glu Val His Leu Thr Pro Val Glu Valine (hydro- phobic) replaces Glutamic Acid (polar)
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Mutations Sickle-cell anemia is caused by a single nucleotide substitution that results in an amino-acid substitution. Such mutations are called “point” mutations. They affect just one nucleotide, as opposed to, say, the deletion (subtraction) or insertion (addition) of several nucleotides. GAA codes for glutamic acid GUA codes for valine
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Point Mutations Synonymous substitutions of nucleotides caused by point mutations do not change amino acids because of redundancy in the genetic code (i.e., more than one codon may code for a particular amino acid. Different types of point mutations have different effects.
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Other types of point mutations Normal A missense mutation causes an amino acid to change (as in the sickle- cell mutation) A nonsense mutation results in a stop codon, which caused translation to end early
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Frameshift Mutations Frameshift mutations alter the reading frame of the RNA. A deletion ( subtraction ) is a loss of a base An insertion ( addition ) is the gain of a base If three bases are added or lost, there is no change in the reading frame, but an amino acid is added or lost in the resulting polypeptide, which could have a major or minor deletion insertion Deletion Insertion
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Summary Can you draw this picture and name all the parts and what they do?
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Chapter 12: The Cell Cycle Cell reproduction: How one cell divides into 2 and how the genetic info gets into the new cells During the cell cycle, an exact copy (a clone) of the original cell is produced. The two cloned cells are called daughter ” cells. DNA replication and distribution: A key element in cell reproduction is the duplication and equal distribution of genetic information—DNA— between the original and the daughter cells. This occurs in the nucleus (for eukaryotes) and is called
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Basic Chromosome-ology Chromosom e (made of chromatin) chromatids Cells create packets of DNA for duplication called chromosomes Each chromosome consist of 1 DNA molecule and various proteins Chromatin is the material of chromosomes. It consists of a complex of DNA and proteins. Chromosomes are chomatin that has condensed into tight, elongate structures, which are visible under a microscope Chromatids are replicated chromosomes (= sister chromatids ) that are attached together at the centromere . Once separated, chromatids are considered chromosomes
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In cell biology, the chromosome number is called the “N number”. It refers to the number of unique chromosomes.
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