Replication that are interspersed about every 100000

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replication that are interspersed about every 100,000 base pairs -single chromosome has few hundred to thousand different genes oyeast relatively small-introns: noncoding intervening sequence found between exons, introns are spliced out of the pre-mRNA prior to translation-exons: segment of RNA that is contained within RNA after splicing has removed the introns. in mRNA, coding sequence of a polypeptide is contained within exons-3 types of regions for replication & segregation: origins of replication, centromeres, telomeres ocentromeres: regions that play a role in the proper segregation of chromosomes during mitosis and meiosis each chromosome: single centromeresite for formation of Kinetochores, which assemble just before andduring early stages of mitosis and meioisKinetochore: composed group of proteins that link the centromereto the spindle apparatus during mitosis and meiosis, ensuring proper segregation of the chromosomes to each daughter celloSaccharomyces cerevisiae: DNA sequence 125bplarger have tandem arrays: regional centromeres -telomeres: specialized repeated sequences found at the ends of linear eukaryotic chromosomes oreplication stability of chromosomeoprevent chromosomal rearrangements such as translocationsoprevent chromosome shorteningprotecting from digestion via enzymes called exonucleases unusual form of DNA replication occurs at the telomere to ensure they donot become shortened Sizes of Eukaryotic Genomes: Genomes sequences moderately repetitive, or highly -different species vary dramatically in size of genomes -sequence complexity: number of times a particular base sequence appears throughout the genome of a given species ounique or nonrepetitive sequences: found once or few times within genome protein-encoding genes are typically unique sequences unique sequences 41% of genomeprotein: 2%, introns: 24%, 15%: unique regions that are not found within genes oModerately repetitive sequences: found few hundred to several thousand times RNA found many copies: necessary for the functioning or ribosomes needlarge amountshistone proteins multiple times: needed structure of chromosome
play role in gene regulation of gene transcription and translationTransportable element (TE): small segment of DNA that can be inserted inmultiple locations within chromosomal DNAnot functional role oHighly repetitive sequences: tens of thousands/ millions of timesrelatively shortAlu family10% of total human DNA and occurs appx every 500-600bpretroelement: transcribed into RNA, copied into DNA, inserted into genometandem array/ repeat: short nucleotide sequence that is repeated many times in a rowEx. AATAT repeated important for proper segregation during meiosis-nucleus: membrane-bound organelle in eukaryotic cell, separate compartmentosingle, linear, double-stranded molecule, hundreds of millions base pairsofolded and compacted by binding-chromatin: complex of DNA and proteins found within each eukaryotic chromosomeo

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