Genetics test 4 real

  1. When eukaryotic cells are stained with DNA specific dyes and viewed under the light microscrope, DNA molecules are revealed in



    D. All of the above
  2. Charles Yanofsky helped decipher the genetic code working with the ___ biosynthesis genes in ___.



    B. tryptophan; Escherichia coli
  3. A codon is a three base sequence of



    D. mRNA that codes for an amino acid
  4. Researchers purified the lac repressor and showed that it actually has two sites for binding. These two distinct binding sites are



    D. lactose binding, DNA binding
  5. The molecules used in a chloroplast to carry our photosynthesis
    a. are all encoded by chloroplast to carry our photosynthesis
    a. are all encoded by chloroplast DNA
    b. some are encoded by chloroplast DNA
    c. are all encoded by nuclear DNA
    d. some are encoded in nucear DNA and some in mitochondrial DNA
    a. some are encoded by chloroplast DNA
  6. Nonsense codons are



    D. some are encoded by chloropast DNA
  7. Which of these is NOT a step in transcription?



    C. replication
  8. Molecules responsible for stimulating the synthesis of a specific protein are called



    D. inducers
  9. Which of the following statements is correct with respect to mitochondrial genes?



    A. They are transmitted, largely intact, from parent to offspring.
  10. The pattern or sequence in which a molecule of mRNA is deciphered by a ribosome is called the



    A. reading frame
  11. Splicing of transcripts normally occurs only in



    A. eukaryotes
  12. In the operon model of gene regulation, transcription is shut off by the binding of repressor to the promoter.
    a. True
    b. False
    b. False
  13. Which of the following has been associated with Alzheimer's Disease?



    C. mutations in cytochrome oxidase c genes in brain cells
  14. There are ______ usually found in the genetic code.



    B. 1 start codon and 3 stop codons
  15. The sequences within mRNA that are spliced out are called



    A. introns
  16. The occurence of constitutive mutations of all three of the lactose utilizing enzymes indicates that their synthesis is regulated together, probably by another gene.
    a. True
    b. False
    a. True
  17. Inhibitors of bacterial translation, such as chloramphenicol and erythromycin, generally



    B. are inhibitors of mitochondrial protein synthesis
  18. The expressed sequences within mRNA that code for gene products are called



    A. exons
  19. A(n) _______ consists of proteins and small nuclear RNAs forming discrete particles that mediate splicing.




    A. splicesome
  20. The transition from transcriptional initiation to elongation involves




    D. release of sigma factor
  21. Molecular evidence suggests that DNA sequences may have been transferred between



    D. All of the above
  22. Which of these is NOT a character of the genetic code?



    C. There are the same number of codons as there are amino acids
  23. RNA molecules that can act as enzymes and catalyze specific biochemical reactions are known as ______




    A. ribozymes
  24. The actual site of binding RNA polymerase in order to initiate transcription is



    C. promoter
  25. Mitochondria and chloroplasts are considered to be semiautonomous.
    a. True
    b. False
    a. True
  26. Aminoacyl-tRNA synthetase is the enzyme that



    A. adds the appropriate amino acid to an uncharged tRNA
  27. rRNA carried an anticodon, which is the complmentary sequence to the mRNA codon that specifies a particular amino acid
    a. True
    b. False
    b. False
  28. What would be the phenotype of a mutation that altered lac repressor function?



    A. constitutive
  29. What type of DNA sequences might be studied to help reunite displace children with their families?



    C. mtDNA
  30. Transcription occurs in the ____ and translation occurs in the ____ of prokaryotic cells.



    D. cytoplasm. cytoplasm
  31. which of the following statements is true under ordinary conditions?



    B. DNA lasts forever within a cell while RNA lasts only for a short time.
  32. RNA polymerase binds to a sequence called a/an _____ before beginning transcription



    D. promoter
  33. The scientists who proposed the operon theory are



    B. Monod and Jacob
  34. Ribosomes are composed of



    B. rRNA and protein
  35. In the modification of eukaryotic mRNA, a "cap" consisting of a/an ___ and a tail consisting of ___ are usually added to the transcript.



    D. methyl group; multiple adenines
  36. A single DNA unit that enables the simultaneous regulation of more than one gene in response to environmental changes is called




    D. operon
  37. Mitocondrial DNA has an approximately 10-fold higher rate of mutation compared to nuclear DNA.
    a. True
    b. False
    a. True
  38. A single DNA unit that enables the simultaneous regulation of more than one gene in response to environmental changes is called




    C. operon
  39. Mitochondrial DNA has an approximately 10-fold higher rate of mutation compared to nuclear DNA
    a. True
    b. False
    a. True
  40. A tRNA that recognizes a nonsense codon and inserts an amino acid where protein synthesis should have stopped is called a



    D. suppressor tRNA
  41. A mutation that occurs when a base is inserted into or deleted from a DNA sequence, completely altering the subsequent amino acid sequence, is called a



    D. frameshift mutation
  42. The universal code of DNA is the same for mtDNA as for chromosomal DNA.
    a. True
    b. False
    b. False
  43. An 60S eukaryotic ribosomal subunit does NOT consist of which of the following rRNAs?



    B. 18S
  44. Except in reverse transcription, RNA is synthesized in a 3' to 5' fashion.
    a. True
    b. False
    b. False
  45. The template and RNA-like DNA strand are equivalent.
    a. True
    b. False
    b. False
Author
kingbken
ID
124056
Card Set
Genetics test 4 real
Description
Genetics test 4 real
Updated