WorksheetsTest 5 pt 2
Total questions: 32
Worksheet time: 16mins
What type of bonding is responsible for maintaining the shape of the tRNA molecule?
hydrogen bonding between base pairs
peptide bonding between amino acids
covalent bonding between sulfur atoms
ionic bonding between phosphates
Why don't highly specialized cells get cancer?
They actually do, they just get it late in life.
Highly specialized cells are missing the genes that create cancer.
Highly specialized cells are unable to undergo mitosis.
These cells only produce mutations in the germ-line cells.
For a couple of decades, biologists knew the nucleus contained DNA and proteins. The prevailing opinion was that the genetic material was proteins, and not DNA. The reason for this belief was that proteins are more complex than DNA. This is most likely because...(common sense answer based on knowledge at the time)
proteins have two different levels of structural organization; DNA has four.
proteins are made of 20 amino acids and DNA is made of four nucleotides.
all of the above are correct
proteins have a greater variety of three-dimensional forms than does DNA.
A frameshift mutation could result from:
a base substitution only.
a base insertion only.
both a base insertion or a base deletion
a base deletion only
This is the mechanism that normally stops cells from forming tumors (cell piles).
contact division
cell-to-cell contact
contact inhibition
cell division
What are ribosomes composed of?
IRNA and proteins
mRNA, IRNA, and proteins
proteins only
IRNA only
The Y-shaped structure where the DNA double helix is actively unwound during DNA replication is called the:
Y junction
replication fork
elongation point
replication Y
What is the function of DNA polymerase?
to add nucleotides to the end of a growing DNA strand
to rejoin the two DNA strands (one new and one old) after replication
to unwind the DNA helix during replication
to seal together the broken ends of DNA strands
What does transformation involve in bacteria?
the creation of a strand of DNA from an RNA molecule
the type of semiconservative replication shown by DNA
the infection of cells by a phage DNA molecule
assimilation of external DNA into a cell
During RNA processing a(n) __ is added to the 5' end of the RNA.
3' untranslated region
5' untranslated region
coding segment
a long string of adenine nucleotides
What are the coding segments of a stretch of eukaryotic DNA called?
transposons
introns
codons
exons
An insertion or deletion causes this effect on the genome:
base substitution
frame-shift mutation
recombination
point mutation
What do Chargaff's rules state?
the amount of A = T and the amount of G = C
all of the above
the amount of A & T, G & C will vary by species
the bases will always exhibit complementary base pairing
A particular eukaryotic protein is 300 amino acids long. Which of the following could be the maximum number of nucleotides in the DNA template strand that codes for the amino acids in this protein?
100
3
900
300
Using RNA as a template for protein synthesis instead of translating protein directly from the DNA is advantageous for the cell because:
Many tRNA molecules can be transcribed from multiple genes, increasing the potential rate of gene expression.
all of the above are reasons
RNA acts as an expendable copy of the genetic material, allowing the DNA to serve as a permanent, pristine repository of the genetic material.
RNA is more stable than DNA.
Each DNA strand is copied by the actions of an enzyme called:
DNA polymerase
DNA replicase
DNA ligase
DNA helicase
In his work with pneumonia-causing bacteria and mice, Griffith found that:
bacteriophages injected DNA into bacteria.
heat-killed pathogenic cells caused pneumonia.
some substance from pathogenic cells was transferred to non-pathogenic cells, making them pathogenic.
the protein coat from pathogenic cells was able to transform non-pathogenic cells.
After DNA replication is completed,
each new DNA double helix consists of two new strands.
each new DNA double helix consists of one old DNA strand and one new DNA strand
each of the four DNA strands consists of some old strand parts and some new strand parts.
one DNA double helix consists of two old strands and one DNA double helix consists of two new strands.
Which of the following is a way to help prevent cancer?
avoid smoking
all of the above are ways to help prevent cancer
avoid salted or smoked foods
eat cabbage family vegetables
A eukaryotic cell lacking active telomerase would:
have a greater potential to become cancerous.
be unable to identify and correct mismatched nucleotides.
be unable to take up DNA from the surrounding solution.
experience a gradual reduction of chromosome length with each replication cycle.
From Rosalind Franklin's X-Ray diffraction data, which of the following was determined about DNA?
All of these were determined.
The molecules had two chains.
The shape of the molecule could be a double helix.
Nitrogenous bases were arranged on the inside of the structure.
Why are hereditary forms of cancer so dangerous?
it takes a long time to get all the necessary mutations
you are automatically born with cancer
a proper diet will not work to help prevent cancer
all the vulnerable cells already have 1 of the 2 necessary mutations
What are the non-coding segments of a stretch of eukaryotic DNA called?
introns
exons
codons
transposons
You briefly expose bacteria undergoing DNA replication to radioactively labeled nucleotides. When you centrifuge the DNA isolated from the bacteria, the DNA separates into two classes. One class of labeled DNA includes very large molecules (thousands or even millions of nucleotides long), and the other includes short stretches of DNA (several hundred to a few thousand nucleotides in length). These two classes of DNA probably represent:
leading strands and RNA primers.
Okazaki fragments and RNA primers.
lagging strands and Okazaki fragments.
leading strands and Okazaki fragments.
Which of the following mutations would be most likely to have a harmful effect on an organism?
a base-pair substitution
a deletion of three nucleotides near the middle of a gene
a single nucleotide deletion near the end of the coding sequence
a single nucleotide insertion downstream of, and close to, the start of the coding sequence
Which of these is a difference between a DNA and an RNA molecule?
DNA is double-stranded, whereas RNA is single-stranded.
DNA contains uracil, whereas RNA contains thymine.
DNA contains five-carbon sugars, whereas RNA contains six-carbon sugars.
DNA is a polymer composed of nucleotides, whereas RNA is a polymer composed of nucleic acids.
Translation occurs where in the cell?
the nucleolus
the cytoplasm
a nucleoplasm
the nucleus
A silent mutation has what effect?
it has no effect
it moves all bases forward one, to make room for the new base
it moves all bases backwards one, to fill in for the lost base
it replaces a base, changing the genetic code at that codon
What do Chargaff's rules state?
the bases will always exhibit complementary base pairing
the amount of A & T, G & C will vary by species
the amount of A = T and the amount of G = C
all of the above
In order to get cancer, cells must...
have 1 of the 2 possible mutations in their alleles already.
be able to reproduce.
be genetically predisposed to forming cancer.
be visible to the sun's ultraviolet radiation.
What is the effect of a nonsense mutation in a gene?
It changes an amino acid in the encoded protein.
It alters the reading frame of the mRNA.
It has no effect on the amino acid sequence of the encoded protein.
It introduces a stop codon into the mRNA.
Once transcribed, eukaryotic mRNA typically undergoes substantial alteration that includes...
fusion into circular forms known as plasmids.
union with ribosomes.
linkage to histone molecules.
excision of introns.
