Protein Synthesis Test Flashcards
What is the monomer of DNA
Nucleotide
What are the 3 parts of a nucleotide
- Phosphate Group
- Sugar
- deoxyribose in DNA
- Ribose in RNA
- Nitrogen base (adenine, thymine, cytosine or guanine)
How are the 2 strands of DNA held together?
Hydrogen Bonds
How are the hydrogen bonds between nitrogen bases important in replication and transcription?
they ensure base pairing specificity and stability of the DNA molecule while still allowing the strands to separate easily
How do nitrogen bases pair up?
pair up according to complementary base pairing rules:
- adenine (A) with thymine (T)
- cytosine (C) with guanine (G).
Describe what Chargraff did to reveal the structure of DNA
Noticed number of A and T bases and the number of C and G bases were always equal
BASE PAIRING RULE - Chargraff’s Rule
Describe what Franklin did to reveal the structure of DNA
Took x-ray diffraction pictures of DNA and noticed a helical shape
Describe what Watson and Crick did to reveal the structure of DNA
Developed first model of structure of DNA; they won the noble prize for their work.
Describe how Griffith discovered the function of DNA
Discovered the transforming principle through his experiments with bacteria, showing that genetic information could be transferred between cells (bacteria) - heredity.
Where in the cell does transcription occur?
Nucleus
Where in the cell does translation occur?
Ribosomes
which can be found in the cytoplasm or attached to the endoplasmic reticulum
What role does mRNA play in gene expression
Carries information from the nucleus to ribosomes
What role does rRNA play in gene expression
Makes up ribosomes, the sites of protein synthesis
What role does tRNA play in gene expression
Positions amino acids in order according to the gene
How are all amino acids similar?
They all have the same common fundamental structure
How are all amino acids different?
different in their side chains or R groups,
What holds amino acids together in a chain?
Peptide bonds
How are some amino acids essential?
the human body cannot synthesize them on its own, so they must be obtained through the diet
What is a codon?
a sequence of three nucleotides on an mRNA molecule that specifies a particular amino acid or a stop signal during protein synthesis
How does translation result in the correct order of amino acids?
mRNA codons are read sequentially by the ribosome,
What are 3 gene mutations
- Substitution (Point mutation): one or more bases are replaced with another
- Insertion: One or more extra nucleotide bases are inserted into the DNA sequence
- Deletion: One or more nucleotide bases are deleted from the DNA sequence
What are 3 amino acid mutations
- Silent:
- Missense:
- Nonsense
Describe the Silent amino acid mutations
Base change has no effect on amino acid sequence
A mutation that changes a codon but does not change the amino acid
Describe the Missense amino acid mutations
Base change causes amino acids to change
A mutation that changes a codon, leading to the incorporation of a different amino acid in the protein
Describe the Nonsense amino acid mutations
Base change causes peptide chain to stop early
A mutation that changes a codon to a stop codon, terminating protein synthesis prematurely
Describe how a frameshit mutation occurs
when nucleotides are inserted into or deleted from the genetic sequence, causing a shift in the reading frame of the codons in mRNA
Describe the consequences of sickle cell trait
Causes red blood cells to become sickle-shaped, leading to anemia, pain, and potential organ damage due to impaired blood flow
What is recombinant DNA?
a form of artificial DNA that is created by combining DNA sequences that would not normally occur together
What is PCR?
Polymerase Chain Reaction
What is the purpose of PCR?
to amplify a specific segment of DNA, creating millions of copies of a particular sequence
What does electrophoresis do?
Use to separate and compare DNA of different organisms or different individuals.
a method used to separate DNA, RNA, or proteins based on size and charge, often used for analysis or purification
What is one use of transformed bacteria?
the production of insulin for diabetic patients
What can scientists use to cut a particular gene out of DNA?
Scientists can use restriction enzymes to cut a particular gene out of DNA
The specificity of genetic material is the result of
Order of the nitrogen bases in DNA
The weakest bonds in a double-stranded molecule of deoxyribonucleic acid exists between the?
Nitrogenous bases
