front 1 Cytoplasmic inheritance | back 1 Refers to transmission of genes on mitochondrial and chloroplast chromosomes, as opposed to nuclear chromosomes. |
front 2 In many eukaryotic species, mitochondria and chloroplasts in fertilized eggs are | back 2 Uniparental |
front 3 Organelle Chromosomes do not..... | back 3 Encode all the proteins needed for mitochondria function. |
front 4 Carl Correns | back 4 Made reciprocal crosses between flowers on branches with differently colored leaves. |
front 5 What were the results from Carl Correns tests? | back 5 Tests showed that progeny invariably exhibited the same phenotype as the female parent in the cross |
front 6 Homoplasmic cells | back 6 Have organelles with the same genotype |
front 7 Hereoplasmic cells | back 7 Contain a mixture of alleles |
front 8 Mitochondrial Mutations can result in | back 8 Human genetic diseases |
front 9 The phenotypes such as diseases are often highly pleitropic because..... | back 9 Because of the dependence of cells on mitochondrial function in oxidative phosphorylation |
front 10 The double-membrane system in chloroplasts and mitchondria is derived | back 10 From a similar membrane system found in bacteria. |
front 11 Are organelles and bacteria similar in size? | back 11 True |
front 12 Organelle DNA is packaged similarly to that of _________, and differently than ____________ _______ | back 12 Bacteria; Nuclear DNA |
front 13 The transcriptional and translational machinery of the organelles closely resembels that of bacteria (T/F) | back 13 True |
front 14 The closest living relatives of mitchondria are | back 14 Free living α-proteobacteria |
front 15 Chloroplasts have also a single origin, descended from a | back 15 Single endosymbiotic event at leat 1.2 billion years ago |
front 16 The closest relatives of chloroplasts are | back 16 Free-living cyanobacteria |
front 17 Regulatory regions of a eukaryotic gene all contain which of the following sequences, which act only on one copy of the chromosome? A) zinc fingers B) cis-acting regulatory sequences C) homeodomains D) trans-acting regulatory sequences E) leucine zippers | back 17 B) cis-acting regulatory sequences |
front 18 You have identified a mutation in a gene which also seems to decrease transcription of another gene 2000 bp away from the mutation site. What regulatory sequence, which may be found within another gene, has likely been mutated in this instance? A) core promoter B) proximal elements C) enhancer sequence D) homeodomain motif E) upstream activator sequence | back 18 C) enhancer sequence |
front 19 In yeast, if you want to prevent the Gal4 regulatory protein from binding near each of the GAL genes, which sequence element would you target? A) core promoter B) proximal elements C) enhancer sequence D) homeodomain motif E) upstream activator sequence | back 19 E) upstream activator sequence |
front 20 In the presence of galactose, you unexpectedly find that transcription is still blocked. Assuming Gal80 is present and functional, which other protein may be mutated to prevent transcriptional activation? A) Gal2 B) Gal3 C) Gal4 D) Mig1 E) Gal10 | back 20 B) Gal3 |
front 21 Galactose is absent, but you find active transcription of the GAL genes. Which protein is likely mutated or absent to allow for constitutive transcription of the GAL genes? A) Gal2 B) Mig1 C) Gal4 D) Gal10 E) Gal80 | back 21 E) Gal80 |
front 22 Which protein binds to the silencer sequence and promotes transcriptional silencing in the presence of glucose? A) Gal2 B) Mig1 C) Gal4 D) Gal10 E) Gal80 | back 22 B) Mig1 |
front 23 If a mouse inherits a deletion in the SHH enhancer, what effect would you expect to see? A) enhanced limb development B) abnormal limb development C) position effect variegation D) increased β-globin production E) abnormal β-globin production (thalassemia) | back 23 B) abnormal limb development |
front 24 Which sequences would likely have both a nucleosome-depleted region (NDR) and a poly A/T tract to attract transcriptional activators to a transcription start sequence? A) chromatin modifiers B) enhancers C) open promoters D) closed promoters E) insulators | back 24 C) open promoters |
front 25 Molecular biologists can determine experimentally whether a region of DNA contains closed chromatin or open chromatin by assessing the sensitivity of the region to A) nucleosomes. B) histone deacetylase. C) RNA polymerase II. D) methyltransferase. E) DNAse. | back 25 E) DNAse. |
front 26 Chromatin remodeling involves both sliding and relocating of the nucleosomes. Which eukaryotic chromatin remodeling complex is likely involved? A) ISWI complex B) SWR1 complex C) SWI/SNF complex D) SHH complex E) Mig1 complex | back 26 C) SWI/SNF complex |
front 27 If you want to affect chromatin packaging, which amino acid could you mutate to affect both histone acetylation and methylation patterns? A) arginine B) methionine C) histidine D) lysine E) asparagine | back 27 D) lysine |
front 28 A region of chromatin has recently become DNAse I hypersensitive. Which enzyme has been activated to cause this change in chromatin structure? A) histone methyltransferase B) histone acetylase C) histone deacetylase D) phosphatase E) kinase | back 28 B) histone acetylase |
front 29 Prader-Willi syndrome is a genetic disorder involving a partial deletion of chromosome 15q on the paternal chromosome. When both copies of a gene (or chromosome) are functional but only one is expressed, this is an example of A) position effect variegation. B) X inactivation. C) genomic imprinting. D) histone acetylation. E) chromatin modifications. | back 29 C) genomic imprinting. |
front 30 When CpG islands are unmethylated, A) chromatin in the promoter region is open, allowing access by transcription factors and RNA polymerase. B) chromatin in the promoter region is closed, preventing transcription factors and RNA polymerase from binding. C) chromatin in the enhancer region is closed, so they are unable to bind regulatory proteins to initiate transcription. D) DNAse hypersensitivity in that region of the chromosome is lost. E) genes downstream of the CpG islands cannot be expressed, because the promoter region is blocked by histones. | back 30 A) chromatin in the promoter region is open, allowing access by transcription factors and RNA polymerase. |
front 31 The imprinting control region (ICR) involved in genomic imprinting on chromosome 15 is what type of sequence? A) enhancer B) insulator C) silencer D) promoter E) intronic | back 31 B) insulator |
front 32 During RNAi, what do miRNAs target for destruction? A) heterochromatic regions of DNA B) CpG islands C) mRNAs D) histones E) ribosomes | back 32 C) mRNAs |
front 33 Many types of cancer are known to overexpress the receptor protein tyrosine kinase. Which molecular technique can be used to reduce expression of an oncogene in vitro? A) PCR B) DNAse sensitivity assay C) RNAi D) Southern blotting E) western blotting | back 33 C) RNAi |
front 34 Inherited mutations in the Xist promoter lead to defects in which epigenetic process? A) RNAi B) X inactivation C) genomic imprinting D) position effect variegation E) methylation of CpG islands | back 34 B) X inactivation |
front 35 Which molecules bind regulatory sequences of DNA to encourage positive regulation of transcription? | back 35 Answer: activator proteins |
front 36 Which protein complex directs DNA bending into loops that contact RNA polymerase and transcription factors bound at the core promoter or with protein complexes bound to proximal promoter elements? | back 36 Answer: enhanceosome |
front 37 What are three proteins you would expect to find bound to the core promoter region in eukaryotes? Answer: TBP, GTFs, and Pol II | back 37 Answer: TBP, GTFs, and Pol II |
front 38 In gal+ yeast, what is the product of the galactose utilization pathway? | back 38 Answer: glucose-1-phosphate |
front 39 In the GAL gene system, which protein acts as an activator protein through its transcription-initiating effect? | back 39 Answer: Gal4 |
front 40 In the GAL gene system, which protein binds to the activation domain of the activator protein, ultimately blocking transcription in the absence of galactose? | back 40 Answer: Gal80 |
front 41 Gal4 is mutated such that it still binds to the DNA but cannot interact with Gal80. What effect would you expect to see in the absence of galactose? | back 41 Answer: transcriptional activation |
front 42 Gal80 is mutated such that it cannot interact with Gal3. What effect would you expect to see in the presence of galactose? | back 42 Answer: Transcription is blocked. |
front 43 Eukaryotes use these highly specialized enhancer elements, which regulate the transcription of multiple genes packaged in complexes of closely related genes (e.g., β-globin). | back 43 Answer: locus control regions (LCRs) |
front 44 What are the protein-binding sequences that direct enhancers to interact with the intended promoter and that block communication between enhancers and other promoter? | back 44 Answer: insulator sequences |
front 45 For the following gene, which mutant likely has lost its enhancer? Mutant # Deletion Region % Transcription WT None 100% 1 1-200 150% 2 250-400 100% 3 500-800 50% 4 950-1100 0% | back 45 Answer: mutant 3 (region 500-800) |
front 46 For the following gene, which type of regulatory sequence has likely been deleted in mutant 1? Mutant # Deletion Region % Transcription WT None 100% 1 1-200 150% 2 250-400 100% 3 500-800 50% 4 950-1100 0% | back 46 Answer: silencer |
front 47 For the following gene, you notice the following results. Mutant # Deletion Region % Transcription (lungs) % Transcription (kidneys) WT None 100% 100% 1 1-200 150% 150% 2 250-400 100% 100% 3 500-800 50% 50% 4 950-1100 0% 100% What type of sequence has been mutated in mutant 4? | back 47 Answer: tissue-specific (lung) promoter |
front 48 What are the two mechanisms by which chromatin remodelers can move nucleosomes? | back 48 Answer: nucleosome sliding and repositioning |
front 49 In yeast, which gene would you expect to be activated during phosphate starvation? | back 49 Answer: PHO5 |
front 50 In vertebrates and plants, what types of modifications to the N-terminal tails of histones lead to heterochromatin formation? | back 50 Answer: deacetylation and methylation |
front 51 Which of the four nucleotides are typically methylated in "islands," resulting in closed chromatin structure? | back 51 Answer: cytosines |
front 52 What effect does methylation of CpG islands have on human promoters? | back 52 Answer: reduced transcription |
front 53 Which protein complex binds dsRNA fragments to generate ssRNAs for RNAi? | back 53 Answer: RNA-induced silencing complex (RISC) |
front 54 Which enzyme cuts dsRNA into 21-25 bp fragments during RNAi? | back 54 Answer: Dicer |
front 55 Gal4 binding leads to the formation of a multiprotein complex known as ________, which is an enhanceosome that forms after the activator protein binds. | back 55 Answer: mediator |
front 56 In the GAL gene system, ________ are cis-acting regulatory elements, and ________ protein is a trans-acting regulatory protein. | back 56 Answer: UASG; Gal4 |
front 57 Demethylation and acetylation lead to open chromatin structure and are associated with ________ regions of genomes. | back 57 Answer: euchromatic |
front 58 ________ in Drosophila results from the movement of the transcriptionally active w+ allele into the centromeric region of the fruit-fly X chromosome. | back 58 Answer: Position effect variegation (PEV) |
front 59 In animals, the ________ enzyme cuts pri-mRNA to produce mi-RNA. | back 59 Answer: Drosha |