39 Questions
What is the structure of DNA?
A double helix
What is the main component of DNA?
Nucleotides
Which of the following is NOT necessary for DNA replication?
RNA nucleotide triphosphates
Which of the following is NOT part of the DNA replication process?
Transcription
What type of replication occurs in eukaryotic cells?
Semi-conservative
What is the genetic code?
A sequence of nucleotides
How many codons are there in the genetic code?
64
What happens during replication?
The parental strands are not degraded
What is the function of RNA primer?
To initiate replication
What is the role of helicase in DNA replication?
To unwind the replication fork
What does tRNA do?
Translates mRNA into the language of amino acids
What is the purpose of tRNA?
To translate mRNA from nucleotides to amino acids
What is the genetic code?
A sequence of nucleotides that specifies the position of an amino acid in a polypeptide
What is the genetic code?
A sequence of nucleotides
What type of replication occurs in the nucleus of eukaryotes?
Semi-conservative
What is the purpose of single-strand binding proteins?
To bind to DNA
What is the main purpose of transcription?
To produce mRNA
What is the direction of elongation during transcription?
Backward
What does the sequence of a gene determine?
The amino acid
What is the role of tRNA in translation?
To translate mRNA from the language of nucleotides into the language of amino acids
What is the genetic code?
A sequence of nucleotides
What type of modification does pre-mature mRNA undergo?
Polyadenylation
What is the approximate shape of a DNA molecule?
Double helix
What is the role of transcription factors?
To initiate transcription
What is the direction of transcription?
From 5' to 3'
What happens during semi-conservative DNA replication?
The parental strands are not degraded
What is the function of tRNA?
To translate mRNA
What is the starting point of the genetic code?
A fixed starting point
What is the purpose of single-strand binding proteins?
To bind to DNA to promote replication
What is the direction of translation?
From 3' to 5'
What is the role of primase in DNA replication?
To add a short RNA sequence (primer) at the start of replication
What is the shape of DNA?
A double helix
What molecule is responsible for initiation of translation?
Activated initiation tRNA
What type of modification occurs during pre-mature mRNA processing?
5’ cap
What is the difference between DNA and RNA nucleotide triphosphates?
RNA nucleotide triphosphates are needed for RNA primer
What is the nearly universal genetic code?
A sequence of nucleotides that specifies the position of an amino acid in a polypeptide
What binds to DNA to promote replication?
Single-strand binding proteins
How does the sequence of a gene determine phenotype?
By determining the amino acid that will be attached to the polypeptide chain
What is the purpose of the 5’ cap?
To protect the mRNA
Study Notes
- DNA is a double helix of paired nucleotides.
- DNA is wound together into a right-handed double helix by two complementary strands.
- The bases project inward from the sugar-phosphate backbones of each strand.
- Double stranded DNA can be unwound/denatured when exposed to changes in temperature, pH, etc.
- Replication occurs in the nucleus of eukaryotic cells, as well as within mitochondria and chloroplasts.
- Replication is semi-conservative, meaning that the parental strands are not degraded.
- DNA polymerases extend DNA by adding nucleotides one at a time.
- Primase adds a short RNA sequence (primer) at the start of replication.
- RNA nucleotide triphosphates are needed for RNA primer.
- DNA nucleotide triphosphates are needed for DNA polymerization.
- Helicase assists in unwinding at the replication fork (ori).
- Single-strand binding proteins bind to DNA to promote replication.
- DNA is transcribed into primary RNA transcripts in eukaryotes.
- Initiation of transcription occurs at specific sites and is dependent on transcription factors.
- Elongation of transcription occurs in the opposite direction.
- Termination of transcription occurs when the RNA polymerase has completed its job.
- Pre-mature mRNA undergoes three modifications: 5’ cap, methylation, and polyadenylation.
- After transcription, mature mRNA is ready for translation.
- The genetic code is the sequence of nucleotides, read 3 at a time, that specifies the position of an amino acid in a polypeptide.
- There are 64 codons combinations, each specifying a different amino acid.
- The code is read, starting from a fixed starting point, as a continuous sequence of successive triplet bases.
- The code is nearly universal, with certain exceptions.
- The genetic code is similar in most organisms, but has slight differences in the mitochondrial DNA of some organisms.
- tRNA is a molecule that is specifically responsible for translating mRNA from the language of nucleotides into the language of amino acids.
- The sequence of a gene helps to determine a phenotype because it determines the amino acid that will be attached to the polypeptide chain.
- tRNA interact with protein (amino acids) at one end and mRNA at another loop.
- Codon/anticodon interaction determines which amino acid is added to the polypeptide chain.
- Once tRNA is charged, it can join with ribosomes and mRNA.
- Initiation of translation occurs when ribosome assembles, complexed with mRNA and activated initiation tRNA, correctly positioned at the start codon.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
