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BIOL 203 MICROBIOLOGY LCC FINAL EXAM (2 LATEST
VERSIONS) / BIOL 203 MICROBIOLOGY LCC FINAL
PREPARATION/BIOL 203 MICROBIOLOGY LCC FINAL
PRACTICE EXAM 2025/2026 NEWEST ACTUAL EXAM WITH
COMPLETE QUESTIONS AND VERIFIED ANSWERS
|ALREADY GRADED A+|
A dogma is a rule. The Central Dogma of Biology is the rule that
governs information transfer in all living things made up of cells.
DNA to RNA to Protein. DNA is made via DNA in the process of
replication, RNA is made via DNA in the process of transcription,
and protein is made via RNA in the process of translation.
Other than topoisomerase and gyrase, name and describe the 6
enzymes/proteins used in DNA replication of the leading strand.
Are the same 6 enzymes/proteins used to replicate the lagging
strand? - ANSWER-The 6 enzymes/proteins used in DNA
replication of the leading strand are
1. Helcase- This breaks the hydrogen bonds and makes them into
two separate strands that will let other enzymes to enter.
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2. Single strand binding proteins- This binds to the newly
separated single strands and makes them stable enough to
prevent them from bonding back together.
3. RNA primase- This gives DNA polymerase a 3' end to build
form by putting down RNA primer.
4. DNA polymerase III- This synthesizes new DNA strands
corresponding to the template strands that are open.
5. DNA polymerase I- This removes the RNA primer nucleotides
and puts DNA nucleotides in the oepn space.
6. Ligase- This fills in the gaps in sugar-phosphate backbone.
The same 6 enzymes/proteins are used to replicate the lagging
strand as well.
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The lagging strand is replicated discontinuously (in Okazaki
fragments.) Why is it not replicated continuously like the leading
strand? Be specific and use enzyme names and directionality in
your answer. - ANSWER-What is the proper direction for DNA
polymerase to work?
The parental strand that is used as the lagging strand template is
in the 5' to 3' direction. DNA polymerase needs a template that is
3' to 5' so that it can lay down nucleotides in the 5' to 3' direction.
Remember that enzymes are very specific as to what substrate
will fit in the active site.
In order for DNA polymerase to replicate the lagging strand it
must jump ahead and work backwards putting the parental strand
in the correct 3' to 5' orientation it needs.
This jumping ahead and working backwards creates many small
fragments that must be linked together by ligase.
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The leading strand template is in the 3' to 5' direction so DNA
polymerase is able to use this as is and lay nucleotides
continuously 5' to 3'.
How is all RNA made? Describe the process of translation in
terms of the three types of RNA discussed in this unit. -
ANSWER-How is the RNA made?
All RNA is made via transcription. For translation to happen, the
cell needs all three types.
mRNA is messenger RNA - it carries the genetic information to
the ribosome and is made up of codons (sets of 3 nucleotides that
code for amino acids)
rRNA is ribosomal RNA - it binds to ribosomal proteins and
together builds the ribosome.
BIOL 203 MICROBIOLOGY LCC FINAL EXAM (2 LATEST
VERSIONS) / BIOL 203 MICROBIOLOGY LCC FINAL
PREPARATION/BIOL 203 MICROBIOLOGY LCC FINAL
PRACTICE EXAM 2025/2026 NEWEST ACTUAL EXAM WITH
COMPLETE QUESTIONS AND VERIFIED ANSWERS
|ALREADY GRADED A+|
A dogma is a rule. The Central Dogma of Biology is the rule that
governs information transfer in all living things made up of cells.
DNA to RNA to Protein. DNA is made via DNA in the process of
replication, RNA is made via DNA in the process of transcription,
and protein is made via RNA in the process of translation.
Other than topoisomerase and gyrase, name and describe the 6
enzymes/proteins used in DNA replication of the leading strand.
Are the same 6 enzymes/proteins used to replicate the lagging
strand? - ANSWER-The 6 enzymes/proteins used in DNA
replication of the leading strand are
1. Helcase- This breaks the hydrogen bonds and makes them into
two separate strands that will let other enzymes to enter.
, Page |2
2. Single strand binding proteins- This binds to the newly
separated single strands and makes them stable enough to
prevent them from bonding back together.
3. RNA primase- This gives DNA polymerase a 3' end to build
form by putting down RNA primer.
4. DNA polymerase III- This synthesizes new DNA strands
corresponding to the template strands that are open.
5. DNA polymerase I- This removes the RNA primer nucleotides
and puts DNA nucleotides in the oepn space.
6. Ligase- This fills in the gaps in sugar-phosphate backbone.
The same 6 enzymes/proteins are used to replicate the lagging
strand as well.
, Page |3
The lagging strand is replicated discontinuously (in Okazaki
fragments.) Why is it not replicated continuously like the leading
strand? Be specific and use enzyme names and directionality in
your answer. - ANSWER-What is the proper direction for DNA
polymerase to work?
The parental strand that is used as the lagging strand template is
in the 5' to 3' direction. DNA polymerase needs a template that is
3' to 5' so that it can lay down nucleotides in the 5' to 3' direction.
Remember that enzymes are very specific as to what substrate
will fit in the active site.
In order for DNA polymerase to replicate the lagging strand it
must jump ahead and work backwards putting the parental strand
in the correct 3' to 5' orientation it needs.
This jumping ahead and working backwards creates many small
fragments that must be linked together by ligase.
, Page |4
The leading strand template is in the 3' to 5' direction so DNA
polymerase is able to use this as is and lay nucleotides
continuously 5' to 3'.
How is all RNA made? Describe the process of translation in
terms of the three types of RNA discussed in this unit. -
ANSWER-How is the RNA made?
All RNA is made via transcription. For translation to happen, the
cell needs all three types.
mRNA is messenger RNA - it carries the genetic information to
the ribosome and is made up of codons (sets of 3 nucleotides that
code for amino acids)
rRNA is ribosomal RNA - it binds to ribosomal proteins and
together builds the ribosome.
