WorksheetsBiol2300+week1+lecture
Total questions: 20
Worksheet time: 15mins
A researcher is comparing two types of cells: one with genes that are actively being transcribed and another with genes that are mostly silent. Which type of chromatin would you expect to find predominantly in each of these cell types?
both cell type would contain primarily euchromatin as this is required for cell survival
The actively transcribed cell would contain mostly euchromatin, while the silent cell would contain mostly heterochromatin.
Both cell types would primarily contain heterochromatin, as this is the default state of DNA.
The actively transcribed cell would contain mostly heterochromatin, while the silent cell would contain mostly euchromatin.
Which of the following is the most fundamental level of DNA packaging that involves DNA interacting directly with histone proteins?
Chromatid
Loop domains
30-nm fiber
Nucleosome
Which of the following is the primary function of centromeres in DNA packaging?
Serving as the point of attachment for spindle fibers during cell division.
Regulating gene expression by controlling chromatin condensation.
Initiating DNA replication.
Protecting the ends of chromosomes from degradation.
Which of the following describes the arrangement of a eukaryotic nucleosome?
A single strand of DNA tightly coiled around itself and stabilized by H1 proteins.
A loop of DNA attached to the nuclear membrane.
DNA complexed with an octamer of eight histone proteins.
A structure consisting of RNA and ribosomal proteins.
During which phase of the cell cycle does chromatin undergo the highest level of compaction to form visible chromosomes?
Interphase
Prophase
Anaphase
Telophase
Which of the following is the most accurate description of a nucleosome?
A structure composed of DNA wrapped around a histone octamer.
A specialized structure at the end of linear chromosomes.
A complex of DNA and RNA molecules tightly wound together.
A highly condensed region of DNA found only in prokaryotes.
Which of the following components are found in a eukaryotic nucleosome?
DNA and a histone octamer composed of two each of H2A, H2B, and H1
DNA, H1 histone, and a histone octamer composed of two each of H2A, H2B, H3, H4, and H5
DNA, H1 histone, and a histone octamer composed of two each of H2A, H2B, and H3
DNA, H1 histone, and a histone octamer composed of two each of H2A, H2B, H3, and H4
Which of the following is the primary function of centromeres in DNA packaging?
Protecting the ends of chromosomes from degradation
Serving as the point of attachment for spindle fibers during cell division.
Regulating gene expression by controlling chromatin condensation.
Initiating DNA replication.
Which of the following describes the arrangement of a eukaryotic nucleosome?
A structure consisting of RNA and ribosomal proteins.
A single strand of DNA tightly coiled around itself and stabilized by H1 proteins.
DNA complexed with an octamer of eight histone proteins.
A loop of DNA attached to the nuclear membrane.
What is the primary role of the centromere in DNA packaging and chromosome function within eukaryotic cells?
To regulate gene expression by controlling the accessibility of DNA to transcription factors.
To initiate DNA replication during the S phase of the cell cycle.
To serve as the site for kinetochore assembly and spindle fiber attachment during cell division.
To protect the ends of chromosomes from degradation and fusion with neighboring chromosomes.
Which of the following best describes the composition of the histone octamer found in eukaryotic nucleosomes?
Two molecules each of H2A, H2B, H3, and H4.
One molecule each of H1, H2A, H2B, H3, and H4.
Four molecules each of H2A and H2B.
Two molecules each of H1, H2A, H2B, and H3.
Which of the following characteristics is associated with heterochromatin rather than euchromatin?
Presence of many genes
Location primarily on chromosome arms
More condensed structure
High transcriptional activity
Which of the following best describes the arrangement of DNA within a eukaryotic cell during metaphase?
Highly condensed into paired chromatids, forming visible chromosomes.
Organized into nucleosomes without further compaction.
Arranged in loop domains attached to the nuclear envelope.
Loosely packed euchromatin to allow active transcription.
Which of the following is a critical function of telomeres in DNA packaging?
Protecting the ends of chromosomes from degradation and fusion.
Facilitating the assembly of nucleosomes along the DNA strand.
Providing a platform for the attachment of RNA polymerase during transcription.
Initiating DNA replication by serving as binding sites for origin recognition complexes.
Which chemical linkage is responsible for connecting nucleotides in a single strand of DNA or RNA?
Peptide bond
Phosphodiester bond
Hydrogen bond
Glycosidic bond
In the Avery, MacLeod, and McCarty experiment, what was the critical finding that led to the conclusion that DNA is the transforming principle?
Heat-killed S cells alone were sufficient to transform R cells into S cells.
Only DNA from S cells was able to transform R cells into S cells.
RNA was shown to be the infectious agent responsible for transformation.
Proteins were shown to be the infectious agent responsible for transformation.
Which of the following components is NOT part of the nucleosome core particle?
Histone H2B
Histone H1
Histone H3
Histone H2A
Which structural feature is common to both prokaryotic and eukaryotic DNA packaging?
The organization of DNA into loop domains to condense the DNA.
The use of histone proteins to form nucleosomes.
The packaging of DNA into a double helix
The presence of telomeres at the ends of chromosomes.
What is the fundamental unit of heredity that confers phenotypes?
Gene
Allele
Chromosome
Nucleotide
In Griffith's experiment, what would have been the expected result if heat-killed S strain Streptococcus pneumoniae was injected into a mouse without the presence of live R strain?
The mouse would develop a different disease unrelated to Streptococcus pneumoniae.
The mouse would become temporarily ill but recover spontaneously.
The mouse would live, as the heat-killed S strain is non-virulent.
The mouse would die due to the virulence of the heat-killed S strain.
