DNA Synthesis
What is the process called in which DNA is copied to create two identical DNA molecules?
DNA Synthesis
What is the central dogma of molecular biology?
DNA--> mRNA--> protein
One gene, one protein model
What is a mutation?
A change in the DNA sequence of a cell
What is gene regulation?
What enzyme is primarily responsible for adding nucleotides to a growing DNA strand during replication?
DNA Polymerase III
What is the function of messenger RNA (mRNA) in gene expression?
Strand of RNA copied from the DNA template strand, which then carries gene instructions to ribosome for protein synthesis.
Name and describe the three types of point mutations.
Silent--> substitution that doesn't change AA sequence
Missense--> substitution that changes one or more amino acid in the sequence
Nonsense--> substitution that causes premature stop codon
How do transcription factors assist in gene regulation?
Transcription factors are proteins that help turn specific genes "on" or "off" by binding to nearby DNA
Describe the role of DNA ligase in DNA synthesis.
join together fragments of newly synthesized DNA to form a seamless strand.
What is the role of ribosomes in the process of translation.
ribosomal subunits assemble together like a sandwich on the strand of mRNA, The read codons and proceed to attract corresponding tRNA molecules tethered to amino acids
How can mutations affect protein synthesis?
They can cause proteins to be made incorrectly or not at all
What is alternative splicing and why is it important?
the process of combining different exons to produce multiple protein variants from a single gene?
What are Okazaki fragments and when do they occur during DNA replication?
Okazaki fragments are created on the lagging strand and are short segments of DNA, as it cannot be synthesized continuously
How do enhancers and silencers influence gene expression?
Enhancers and silencers regulate transcription by increasing or decreasing the rate of gene expression
What is the difference between a somatic mutation and a germline mutation?
somatic mutations occur after conception and do not affect offspring
germline mutations effect offspring
Describe the role of epigenetics in gene regulation.
Epigenetic changes are modifications to DNA that regulate whether genes are turned on or off as a result of environmental influence.
Explain the difference between leading strand and lagging strand during DNA replication.
the leading strand is synthesized continuously and the lagging strand is synthesized in short segments (Okazaki fragments)
Explain the process of transcription and the role of RNA polymerase.
Transcription is the process in which a gene's DNA sequence is copied (transcribed) to make an RNA molecule. RNA polymerase is the main transcription enzyme. Transcription begins when RNA polymerase binds to a promoter sequence near the beginning of a gene
Name one benefit and one drawback of mutations
benefit: crucial for evolution and genetic diversity
drawback: can cause disease
Name one mechanism by which gene expression can be regulated at the transcription level.
What is the binding of transcription factors to promoter regions