General Biology Test #3 Molecular Biology And Cell Reproduction

50 Questions | Total Attempts: 1801

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General Biology Test #3 Molecular Biology And Cell Reproduction


Questions and Answers
  • 1. 
    Waston and Crick built models that demonstrated that
    • A. 

      DNA and RNA have the same structure.

    • B. 

      DNA is made of two strands that twist into a double helix.

    • C. 

      Guanine forms hydrogen bonds with adenine.

    • D. 

      Thymine forms hydrogen bonds with cytosine.

  • 2. 
    Molecules of DNA are composed of long chains of 
    • A. 

      Amino acids.

    • B. 

      Fatty acids.

    • C. 

      Monosaccharides.

    • D. 

      Nucleotides.

  • 3. 
    The entire molecule shown in the diagram is called a(n)
    • A. 

      Amino acids.

    • B. 

      Nucleotide.

    • C. 

      Polysaccharide.

    • D. 

      Pyrimidine.

  • 4. 
    Cancer cells that spread are called
    • A. 

      Benign

    • B. 

      Malignant

    • C. 

      Somatic

    • D. 

      Gametic

  • 5. 
    Using radioactive tracers (shown below) to determine the interactions of bacteriophages and their host bacteria, Hershey and Chase demonstrated without question that
    • A. 

      Genes are compose of protein molecules

    • B. 

      DNA and proteins are actually the same molecules located in different parts of the cells.

    • C. 

      Bacteria injects their DNA into the cytoplasm of bacteriophages.

    • D. 

      DNA is the molecule that stores genetic information in the cells.

  • 6. 
    In humans, gametes contain
    • A. 

      22 autosomes and 1 sex chromosome.

    • B. 

      1 autosome and 22 sex chromosomess.

    • C. 

      45 autosome and 1 sex chromosome.

    • D. 

      1 autosome and 45 sex chromosomes.

  • 7. 
    The X and Y chromosomes are called the
    • A. 

      Extra chromosomes.

    • B. 

      Phenotypes.

    • C. 

      Sex chromosomes.

    • D. 

      All of the above.

  • 8. 
    Normal humans males develop from fertilized eggs containing which of the following sex chromosome combinations?
    • A. 

      XY

    • B. 

      XX

    • C. 

      XO

    • D. 

      OO

  • 9. 
    Chromatids are
    • A. 

      Dense patches within the nucleus.

    • B. 

      Bacterial chromosomes.

    • C. 

      Joined strands of duplicated genetic material (chromosome)

    • D. 

      Prokaryotic nuclei.

  • 10. 
    A strand of DNA has the following sequence of bases: ATC GTC TTC AAG What sequence of bases will make up the other strand of DNA?
    • A. 

      TAG CAG AAG TTC

    • B. 

      UUC AAG CAG UAG

    • C. 

      UAG CAG AAG UUC

    • D. 

      GTC ATC AAG TTC

  • 11. 
    Griffith's transformation experiments shown below
    • A. 

      Changed proteins into DNA.

    • B. 

      Caused non-harmful bacteria to become deadly.

    • C. 

      Resulted in DNA molecules becoming proteins.

    • D. 

      Were design to show the effect of heat on bacteria.

  • 12. 
    The point at which two chromatids are attached to each other in a chromosome is called a(n)
    • A. 

      Chloroplast.

    • B. 

      Centromere.

    • C. 

      Gamete.

    • D. 

      Centriole.

  • 13. 
    The diploid number of chromosomes in a human skin cells is 46. The number of chromosomes found in a human ovum (egg) is 
    • A. 

      46

    • B. 

      92

    • C. 

      23

    • D. 

      12.5

  • 14. 
    At the very beginning of the translation, the first tRNA molecule
    • A. 

      Binds to the ribosome's A site.

    • B. 

      Attaches directly to the DNA codon.

    • C. 

      Connects an amino acid to its anticodon.

    • D. 

      Attaches to the P site of the ribosome.

  • 15. 
    • A. 

      Suspect A

    • B. 

      Suspect B

    • C. 

      No suspect matches the DNA fingerprint

  • 16. 
    The non-coding portions of DNA that are separated from the portions of DNA actually used during transcription are called
    • A. 

      Mutons

    • B. 

      Exons

    • C. 

      Introns

    • D. 

      Exposons

  • 17. 
    Many biologists believe that having the genes of eukaryotic cells interrupted by introns
    • A. 

      Prevents the code from being corrected.

    • B. 

      Ensured severely damaging mutations.

    • C. 

      Ensures that replication occurs correctly.

    • D. 

      Provides evolutionary flexibility.

  • 18. 
    The lac operon is shut off when
    • A. 

      Lactose is present.

    • B. 

      Lactose is absent.

    • C. 

      Glucose is present.

    • D. 

      Glucose is absent.

  • 19. 
    The portions of DNA molecules that actually code for the production of proteins are called
    • A. 

      Mutons

    • B. 

      Exons

    • C. 

      Introns

    • D. 

      Exposons

  • 20. 
    Refer to the illustration below. Where on the lac operon does transcription take place?
    • A. 

      Promoter (p)

    • B. 

      Operator (o)

    • C. 

      Gene (z)

  • 21. 
    The function of an operator is to?
    • A. 

      Regulate access of RNA polymerase to specific genes.

    • B. 

      Turn on and off the molecules of tRNA.

    • C. 

      Control the process of transcription within the nucleus.

    • D. 

      Generate amino acids for protein synthesis.

  • 22. 
    Cells must control gene expression so that
    • A. 

      Their genes will only be expressed when needed.

    • B. 

      Their genes will always be expressed.

    • C. 

      Their genes will never be expressed.

    • D. 

      Genetic disorders can be corrected.

  • 23. 
    A repressor protein
    • A. 

      Prevents DNA synthesis.

    • B. 

      Blocks movement of RNA polymerase.

    • C. 

      Attaches to ribosome during translation.

    • D. 

      Destroys amino acids before protein synthesis occurs.

  • 24. 
    Refer to the illustration below. To which portion of the lac operon does the repressor bind?
    • A. 

      Promoter (p)

    • B. 

      Operator (o)

    • C. 

      Gene (z)

  • 25. 
    The anticodons on the tRNA molecule for the codons in the mRNA: CUCAAGUCCUUC would be
    • A. 

      GAG--UUC--AGG--AAG.

    • B. 

      GAG--TTC--ACG--AAG.

    • C. 

      CUC--GAA--CGU--CUU.

    • D. 

      CUU--CGU--GAA--CUC.