What is semi-conservative replication?
Each new DNA molecule contains one original strand and one newly synthesised strand.
This method of replication helps maintain genetic continuity.
What enzyme unwinds DNA during replication?
DNA helicase
It breaks the hydrogen bonds between the complementary base pairs.
What enzyme forms phosphodiester bonds during replication?
DNA polymerase. DNA polymerase joined adjacent nucleotides together to form a new sugar phosphate backbone of the mRNA
What are activated nucleotides?
Free DNA nucleotides with extra phosphate groups providing energy for bond formation
These nucleotides are ready for incorporation into the growing DNA strand.
What are spontaneous mutations?
Random errors in DNA replication such as base insertions, deletions or substitutions.
These mutations can occur without external influences.
When does DNA replication occur?
During the S phase of interphase of the cell cycle.
This phase is specifically dedicated to DNA synthesis.
Why does semi-conservative replication increase accuracy?
Semi-conservative DNA replication increases accuracy because each new DNA molecule contains one original (parent) strand and one newly synthesised strand. During replication the original strand acts as a template and because the original strand is a correct strand the chance of errors is reduced as it ensures complementary base pairing occurs so the correct nucleotides are added to the new strand.
This process helps to reduce the chances of mutations
Why must DNA be replicated before cell division
To ensure that each daughter cell receives a complete and identical set if genetic information
Why to the two DNA strands separate during replication?
To expose template strands so complementary nucleotides can bind
Why are free nucleotides attracted to exposed bases?
Because of complementary base pairing occurs
What type of reaction does DNA polymerase catalyse
Condensation reaction between deoxyribose sugar and phosphate groups
What does genetic continuity mean?
The preservation of identical genetic information between parent and daughter cells
Why is genetic continuity important in multicellular organisms?
Because cells are regularly replaced and new cells must preform the same function as parent cells
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2.1.2 - Fundementals Of Biological Molucles13
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2.1.2 - Molecular Building Blocks25
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2.1.2 - Properties Of Water24
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2.1.2 - Sugars And Carbohydrates18
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2.1.2 - Inorganic Componds12
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2.1.2 - Test For Biological Molecules15
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2.1.1 - Cell Biology40
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2.1.1 - Cell Structure36
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2.1.1 - Organelles And The Production Of Proteins11
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2.1.1 - The Cytoskeleton11
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2.1.3 - Nucleotides And Phosphodiester Bonds17
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2.1.5. - The Plasma Membrane39
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2.3.1 - Nucleic Acids15
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2.2 - The Cell Surface Membrane32
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The Cell Cycle18
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The Stages Of Mitosis11
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The Mammalian Gas Exchange System34
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DNA & RNA Structure - Nucleotides18
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Phosphodiester Bonds & Sugar Phosphate Backbone6
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The Genetic Code18
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DNA Replication13
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Transcription19
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Translation18
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Protein Structure36
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Specilised Cells35
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Gas Exchange In Animals30
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Gas Exchange In Insects And Fish25
