Chapters 16 Exam 2
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| 555073798 | 2 DNA strands are held together by.... | Hydrogen bonds between nitrogenous bases | |
| 555073799 | pairs of nitrogenous bases in DNA double helix are held together by.... | Hydrogen bonds | |
| 555073800 | First step in basic DNA replication | strands separate, each parental strand serves as a template that determines the order of nucleotides along a new complementary strand | |
| 555073801 | Second step in basic DNA replication | complementary nucleotides line up and and connect to sugar-phosphate backbones of the new strands. Each strand consists of 1 parent strand, 1 daughter strand | |
| 555073802 | Conservation Model of DNA replication | 2 parental strands reassociate after acting as templates for new strands, thus restoring the parental double helix | |
| 555073803 | Semiconservative Model of DNA replication | 2 strands of the parental molecule separate, and each functions as a template for synthesis of a new, complementary strand | |
| 555073804 | Dispersive Model of DNA replication | Each strand of both daughter molecules contain a mixture of old and newly synthesized DNA | |
| 555073805 | Replication Fork | Y shaped region where parental strands of DNA are being unwound | |
| 555073806 | Helicases | Enzymes that unwinds and separates the parental DNA strands to become template strands | |
| 555073807 | Single-strand binding proteins | bind to unpaired DNA strands, stabilize unwound parent strands | |
| 555073808 | Topoisomerase | breaks, swivels, and rejoins parental DNA ahead of the replication fork, relieving the strain caused by unwinding | |
| 555073809 | The initial nucleotide chain that is produced during DNA synthesis is.... | a short stretch of RNA | |
| 555073810 | Primer | short stretch of RNA | |
| 555073811 | Primase | Synthesizes the primer Starts a complementary RNA chain from a single RNA nucleotide adding RNA nucleotides one at a time, using the parental DNA strand as a template | |
| 555073812 | DNA polymerases | Catalyze the synthesis of new DNA by adding nucleotides to a preexisting chain Require a primer and DNA template strand | |
| 555073813 | Leading strand | The new complementary DNA strand synthesized continuously along the template strand toward the replication fork in the mandatory 5' to 3' direction | |
| 555073814 | Lagging strand | A discontinuously synthesized DNA strand that elongates by means of Okazaki fragments, each synthesized in a 5' to 3' direction away from the replication fork | |
| 555073815 | Okazaki fragments | A short segment of DNA synthesized away from the replication fork on a template strand during DNA replication. Many such segments are joined together to make up the lagging strand of newly synthesized DNA | |
| 555073816 | Synthesis of lagging strand Step 1 | Primase joins RNA nucleotides into primer | |
| 555073817 | Synthesis of lagging strand Step 2 | DNA pol II adds DNA nucleotides to the primer, forming Okazaki fragment 1 | |
| 555073818 | Synthesis of lagging strand Step 3 | After reaching the next RNA primer to the right, DNA pol III detaches | |
| 555073819 | Synthesis of lagging strand Step 4 | Fragment 2 is primed, Then DNA pol III adds DNA nucleotides, detatching when it reaches the fragment 1 primer | |
| 555073820 | Synthesis of lagging strand Step 5 | DNA pol I replaces the RNA with DNA, adding to the 3' end of fragment 2 | |
| 555073821 | Synthesis of lagging strand Step 6 | DNA ligase forms a bond between the newest DNA and the DNA of fragment 1 | |
| 555073822 | Synthesis of lagging strand Step 7 | Laggin strand in this region is now complete | |
| 555073823 | REVIEW FIGURE 16.17. pg. 317 | ... | |
| 555073824 | Mismatch repair | Celluar process that uses specific enzymes to remove and replace incorrectly paired nucleotides | |
| 555073825 | Nuclease | cuts damanged DNA strand at two points so damaged section can be removed | |
| 555073826 | Nucleotide excision repair | DNA repair system | |
| 555073827 | Enzymes involved with filling pre-damaged gap | DNA polymerase and DNA ligase | |
| 555073828 | Telomeres | Tandemly repetitive DNA at the end of a eukaryotic chromosome's DNA molecule. Telomeres protect the organism genes from being eroded during successive rounds of replication. | |
| 555073829 | Nucleoid | Dense region of DNA is bacterium | |
| 555073830 | Histones | Proteins that are responsible for the first level of DNA packing in chromatin | |
| 555073831 | Nucleosome | Basic unit of DNA packing. Consists of DNA wound twice around a protein core composed of two molecules each of the four main histone types | |
| 555073832 | Chromatin | Complex of DNA and proteins hat makes up eukaryotic chromosomes. When the cell is not dividing, chromatin exists in its dispersed form, as a mass of very long, thin fibers |
