Week 19 Flashcards
What is translation
Translation is the process where the genetic code carried by messenger RNA (mRNA) is decoded to produce a specific sequence of amino acids, which fold into a functional protein
Broadly describe how amino acids make up polypeptides, and how polypeptides become proteins
Amino acids are linked together by peptide bonds to form polypeptide chains (primary structure). These chains fold into secondary structures (alpha helices or beta sheets), further fold into tertiary structures (3D shapes based on R-group interactions), and sometimes combine into quaternary structures if multiple polypeptides are involved, creating mature, functional proteins.
Summarize the role of tRNA and ribosomes in the
process of translation.
tRNA delivers specific amino acids to the growing polypeptide chain by matching its anticodon with the mRNA codon. Ribosomes act as the molecular machinery that assembles amino acids into polypeptides. The ribosome has binding sites (E, P, A) that guide tRNA movement and ensure proper codon-anticodon pairing.
Name and identify the 4 levels of protein structure, and identify which stages can be mature, functional proteins.
Primary structure: Sequence of amino acids in a polypeptide chain.
Secondary structure: Local folding patterns such as alpha helices or beta sheets.
Tertiary structure: The 3D structure formed by further folding of the polypeptide.
Quaternary structure: Assembly of multiple polypeptides into a single functional unit.
Some proteins are functional at the tertiary level, while others require a quaternary structure for functionality (e.g., hemoglobin).
Transcription
Copying DNA info and editing it
Proteins are .____ . made up of ________
polypeptides, amino acid monomers
tRNA is and does what
“Transfer RNA” it transfers amino acids to growing polypeptide strand
How does tRNa read the mRNA codon
By using the anticodon end of its tructure
Ribosomes do what
Are the machines that link amino acids together to make polypeptide
LO
Explain why mutation is the basis of new genetic diversity
Mutations alter the nucleotide sequence of DNA or RNA, creating new alleles that lead to novel traits. This process is the only source of entirely new genetic material and is essential for generating the variation needed for natural selection to act upon.
LO
Differentiate between somatic and germline mutations, and identify which has implications for heredity.
Somatic mutations occur in body cells, cannot be inherited, and may lead to conditions like cancer.
Germline mutations occur in gametes (eggs or sperm), are passed to offspring, and can have neutral, harmful, or beneficial effects.
Only germline mutations impact heredity.
LO
Define 3 general types of mutations and
identify them in a series of nucleotides.
Point mutations: Single base substitutions that can result in silent, missense, or nonsense mutations.
Insertions: Addition of one or more nucleotides, potentially causing a frameshift.
Deletions: Loss of one or more nucleotides, which can also cause frameshifts.
Examples of each mutation type can be identified by observing changes in nucleotide sequences.
LO
Describe 3 reasons why most mutations have
little to no effect on organisms.
Somatic mutations do not affect gametes and thus do not impact offspring.
The genetic code is redundant, meaning multiple codons can code for the same amino acid.
Diploid organisms have two copies of each gene, so a functional copy can compensate for a mutated one.
Only source of novel traits
mutation
How do mutations occur
DNA fails to replicate or repair accurately