Bio 101 Module 3 test (Questions and Answers A+ Graded 100% Verified)

Bio 101 Module 3 test (Questions and Answers A+ Graded 100% Verified) A diploid cell has ____ the number of chromosomes as haploid cells ANS: twice the first level of DNA organization in a eukaryotic cell is maintained by which molecule? ANS: chromatin identical copies of chromatin held together by cohesin at the centromere are called _____? ANS: sister chromatids Chromosomes are duplicated during what stage of the cell cycle? ANS: S phase which of the following events does not occur during some stages of interphase? ANS: separation of sister chromatids the mitotic spindle fibers arise from which cell structure? ANS: centrosome the attachment of the mitotic spindle fibers to the kinetochores is a characteristic of what stage of mitosis? ANS: prometaphase unpacking of chromosomes and and the formation of a new nuclear envelope is a characteristic of which stage of mitosis ANS: telophase separation of the sister chromatids is a characteristic of which stage of mitosis? ANS: anaphase the chromosomes have become visible under a light microscope during which stage of mitosis? ANS: prophase the fusing of Golgi vesicles at the metaphase plate of dividing plant cells forms what structure? ANS: cell plate at which of the cell cycle checkpoints do external forces have the greatest influence? ANS: G1 checkpoint what is the main prerequisite for clearance at the G2 checkpoint? ANS: Accurate and complete DNA replication if the M checkpoint is not cleared, what stage of mitosis will be blocked? ANS: Anaphase Meiosis usually produces _____ daughter cells. ANS: four haploid what structure is most important when forming the tetrads? ANS: synaptonemal complex at which stage of meiosis are sister chromatids separated? ANS: anaphase II At metaphase I, homologous chromosomes are connected only at what structure? ANS: kinetochores the part of meiosis that is similar to mitosis is _______. ANS: Meiosis II is a muscle cell of a typical organism has 32 chromosomes, how many chromosomes will be in a gamete of that same organism ANS: 16 which statement best describes the genetic content of the two daughter cells in prophase II of meiosis? ANS: diploid with two copies of each gene the pea plants used in Mendel's genetic inheritance studies were diploid, with 14 chromosomes in somatic cells. assuming no crossing over events occur, how many unique gametes could one pea plant produce? ANS: 16,384? how does telophase I and telophase II differ during meiosis in animal cells? ANS: cells remain diploid at the end of telophase I, but are haploid at the end of telophase II what is a likely evolutionary advantage of sexual reproduction over asexual reproduction? ANS: sexual reproduction results in variation of the offspring which types of life cycle has both a haploid and diploid multicellular stage? ANS: alternation of generations a diploid, multicellular life-cycle stage that gives rise to haploid cells by meiosis is called a _____. ANS: sporophyte if DNA of a particular species was analyzed and found that it contains 27% A, what would be the percentage of C ANS: 23% During proofreading, which of the following enzymes reads the DNA? ANS: DNA pol The AUC and AUA codons in mRNA both specify isoleucine. what feature of the genetic code explains this? ANS: Degeneracy DNA double helix does not have which of the following? ANS: uracil in eukaryotes what is DNA wrapped around? ANS: histones Meselson's and Stahl's experiment proved that DNA replicates by which mode? ANS: semi-conservative which of the following components is not involved during the formation of the replication fork? ANS: ligase which of the following does the enzyme primase synthesize? ANS: RNA Primer in which direction does DNA replication take place? ANS: 5'-3' how many nucleotides are in 12 mRNA codons? ANS: 36 which event contradicts the central dogma of molecular biology? ANS: scientists use reverse transcriptase enzymes to make DNA from RNA how do enhancers and promoters differ? ANS: enhancers increase the efficiency of gene expression, but are not essential for transcription. Promoter recognition is essential to transcription initiation which pre-mRNA processing step is important for initiating translation ANS: 7-methylguanosine cap the RNA components of ribosomes are synthesized in the ____. ANS: nucleolus