exam 1

Until the mid-1940s, many scientists considered proteins to be the likely candidates for the genetic material. Which of the following characteristics le scientists to believe DNA was not the genetic material?
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Terms in this set (44)
which of the following is true about sex-determining chromosomes?They act like homologous chromosomes during meiosis so each gamete will get one sex chromosomeThe house fly, Musca domestica has a haploid chromosome number of 6. How many chromatids should be present in a diploid, somatic, metaphase cell?24The nucleus organizer region (NOR) is responsible for production of what type of cell structure?RibosomeHow many haploid sets of chromosomes are present in an individual cell that is pentaploid (5n)?5After meiosis 2 _____ would be formedmonadsThere is about as much nuclear DNA in a primary spermatocyte as in ________ (how many) spermatids?4A diploid somatic ("body") cell has 2n=20 chromosomes. At the end of mitosis, each daughter cell would have_____ chromosomes. At the end of meiosis 1, each daughter cell would have______ chromosomes . At the end of meiosis 2 , each daughter cell would have______ chromosomes.2n=20 1n=10 1n=10If this cell was isolated from a diploid organism, it is probably inprophase 2which of the following is true about the second meiotic division?sister chromatids are pulling apartDuring meiosis, the chromosome number reduction takes place in______anaphase 1what is the outcome of synapsis, a significant event in meiosis?side-by-side alignment of homologous chromosomesduring oogenesis in animals,there can be very long time gaps (years) between one stage and the nextTransduction is a form of recombination in bacteria that involves ________.bacteriophagesWhat is a form of recombination in bacteria that involves the F plasmid?conjugationIf two loci cotransform frequently, _______________they are closely linked_______ bacteria contain F factor or plasmid that is capable of initiating conjugation._______ bacteria contain F plasmid that possesses a portion of the bacterial chromosomeF+, Merozygotes_____ can exist integrated into the bacterial chromosome or as an autonomous plasmid unit in the cytosolEpisomesBacteriophages engage in two interactive cycles with bacteria . what are these cycles?lytic and lysogenicName the general category into which double-stranded circular extrachromosomal DNA elements such as F factors, ColE1, and R would fall.plasmidDuring DNA replication_____ are 1000-2000 nucleotide long strands synthesized on the___ strand to maintain the ____ of replicationOkazaki fragments; lagging; bidirectionalityThe amount of DNA that is replicated from a single origin of replication is referred to as a(n) ______repliconDNA replication in Eukaryotes ____initiates at multiple originswhich of the following statements is not an essential step in homologous recombination?exonuclease degradationwhich of the following statements about the oirC region in E.coli is incorrect?it is directly recognized and bound by DNA helicase.DNA replication proceeds _____semiconservativelyThe discontinuous aspect of replication of DNA in vivo is caused by ________the 5' to 3' polarity restrictionTelomerase adds nucleotides to the _____3' end of the parental strandDNA polymerase 1 is thought to add nucleotides_______in the place of the primer RNA after it is removedDNA polymerase III adds nucleotides ______to the 3' end of the RNA primerAs unwinding of the helix occurs during DNA replication, tension is referred to as ______ is created ahead of the replication fork. This tension is relieved by the action of _____supercoiling; DNA gyraseThe protein responsible for the initial step in unwinding the DNA helix during replication of the bacterial chromosome is coded for by the ____ genednaAWhich cluster of terms accurately reflects the nature of DNA replication in prokaryotes?fixed point of initiation, bidirectional, semiconservativeDNA replication occurs by adding_____dNTPs to the 3' end of the daughter strandChromatin is defined as ________.DNA complexed with protein