PRAXIS BIOLOGY (5236) MODULE 3
EXAM QUESTIONS AND ANSWERS
DNA - Correct Answers -A double strand of nucleotides wrapped around a histone
protein
Nucleotide - Correct Answers -Composed of: a phosphate group, a deoxyribose sugar,
a nitrogen base
4 Nitrogenous Bases - Correct Answers -Adenine, Thymine, Cytosine, and Guanine
Chargaff's Rule - Correct Answers -[A]=[T] and [G]=[C], they pair up across from one
another forming two strands also called base pairing.
Gene - Correct Answers -a particular section of DNA that encodes for a particular trait
Chromatin - Correct Answers -the complex of proteins and DNA that will eventually form
chromosomes
Allopatric Speciation - Correct Answers -occurs when in populations of the same
species are physically separated from each other
Sympatric Speciation - Correct Answers -occurs when populations of the same species
live in the same geographic area, but still become reproductively isolated
Genetic Evolution Factors - Correct Answers -Gene flow and mutations
Non-Genetic Evolution Factors - Correct Answers -genetic drift and non-random mating
Fossil Record - Correct Answers -information about past life, including the structure of
organisms, what they ate, what ate them, in what environment they lived, and the order
in which they lived
Chromosomes - Correct Answers -tightly coiled strands of DNA, largest unit of genetic
information
DNA Structure - Correct Answers -double helix; held together by complimentary base
pairing
RNA Structure - Correct Answers -single-stranded
, RNA Bases - Correct Answers -adenine, guanine, cytosine, uracil
Central Dogma of DNA - Correct Answers -DNA -> RNA -> Protein
DNA Replication - Correct Answers -1) DNA Helicase unzips DNA 2) DNA Polymerase
moves along the exposed strand of DNA and adds the complimentary bases 3) DNA
Ligase catalyzes attachment of strands back together
Okazaki Fragments - Correct Answers -Small fragments of DNA produced on the
lagging strand during DNA replication, joined later by DNA ligase to form a complete
strand.
RNA Transcription - Correct Answers -1) Transcription factors bind to a gene's
promoters 2) RNA Polymerase binds to the transcription factors 3) RNA Polymerase
attaches the complementary RNA 4) Transcription stops when the RNA Polymerase
reaches a "stop" signal
Capping - Correct Answers --Modified guanosine attached to 5' end
-Needed for mRNA to exit nucleus and bind ribosome
Splicing - Correct Answers -the process of removing introns and reconnecting exons in
a pre-mRNA
Polyadenylation - Correct Answers -The addition of a string of adenine nucleotides
added to the mRNA after transcription.
Transfer RNA (tRNA) - Correct Answers -An RNA molecule that functions as an
interpreter between nucleic acid and protein language by picking up specific amino
acids and recognizing the appropriate codons in the mRNA
Messenger RNA (mRNA) - Correct Answers -RNA molecule that carries copies of
instructions for the assembly of amino acids into proteins from DNA to the rest of the
cell
Start Codon - Correct Answers -AUG
Stop Codons - Correct Answers -UAA, UAG, UGA
Codon - Correct Answers -set of three bases
Translation - Correct Answers -1) mRNA combines with rRNA and tRNA 2) mRNA bond
to the anticodons of tRNA and brings the correct amino acid 3) Amino acid chain is
bonded together by enzymes 4) Stop codon is reached
EXAM QUESTIONS AND ANSWERS
DNA - Correct Answers -A double strand of nucleotides wrapped around a histone
protein
Nucleotide - Correct Answers -Composed of: a phosphate group, a deoxyribose sugar,
a nitrogen base
4 Nitrogenous Bases - Correct Answers -Adenine, Thymine, Cytosine, and Guanine
Chargaff's Rule - Correct Answers -[A]=[T] and [G]=[C], they pair up across from one
another forming two strands also called base pairing.
Gene - Correct Answers -a particular section of DNA that encodes for a particular trait
Chromatin - Correct Answers -the complex of proteins and DNA that will eventually form
chromosomes
Allopatric Speciation - Correct Answers -occurs when in populations of the same
species are physically separated from each other
Sympatric Speciation - Correct Answers -occurs when populations of the same species
live in the same geographic area, but still become reproductively isolated
Genetic Evolution Factors - Correct Answers -Gene flow and mutations
Non-Genetic Evolution Factors - Correct Answers -genetic drift and non-random mating
Fossil Record - Correct Answers -information about past life, including the structure of
organisms, what they ate, what ate them, in what environment they lived, and the order
in which they lived
Chromosomes - Correct Answers -tightly coiled strands of DNA, largest unit of genetic
information
DNA Structure - Correct Answers -double helix; held together by complimentary base
pairing
RNA Structure - Correct Answers -single-stranded
, RNA Bases - Correct Answers -adenine, guanine, cytosine, uracil
Central Dogma of DNA - Correct Answers -DNA -> RNA -> Protein
DNA Replication - Correct Answers -1) DNA Helicase unzips DNA 2) DNA Polymerase
moves along the exposed strand of DNA and adds the complimentary bases 3) DNA
Ligase catalyzes attachment of strands back together
Okazaki Fragments - Correct Answers -Small fragments of DNA produced on the
lagging strand during DNA replication, joined later by DNA ligase to form a complete
strand.
RNA Transcription - Correct Answers -1) Transcription factors bind to a gene's
promoters 2) RNA Polymerase binds to the transcription factors 3) RNA Polymerase
attaches the complementary RNA 4) Transcription stops when the RNA Polymerase
reaches a "stop" signal
Capping - Correct Answers --Modified guanosine attached to 5' end
-Needed for mRNA to exit nucleus and bind ribosome
Splicing - Correct Answers -the process of removing introns and reconnecting exons in
a pre-mRNA
Polyadenylation - Correct Answers -The addition of a string of adenine nucleotides
added to the mRNA after transcription.
Transfer RNA (tRNA) - Correct Answers -An RNA molecule that functions as an
interpreter between nucleic acid and protein language by picking up specific amino
acids and recognizing the appropriate codons in the mRNA
Messenger RNA (mRNA) - Correct Answers -RNA molecule that carries copies of
instructions for the assembly of amino acids into proteins from DNA to the rest of the
cell
Start Codon - Correct Answers -AUG
Stop Codons - Correct Answers -UAA, UAG, UGA
Codon - Correct Answers -set of three bases
Translation - Correct Answers -1) mRNA combines with rRNA and tRNA 2) mRNA bond
to the anticodons of tRNA and brings the correct amino acid 3) Amino acid chain is
bonded together by enzymes 4) Stop codon is reached
