8 - DNA, Genes, and Protein Synthesis Flashcards
Describe how a gene is a code for the production of a polypeptide. Do not include information about transcription or translation in your answer. (3)
Base sequence
Read in triples
Determines sequence of amino acids
Define the term exon. (1)
Base sequence coding for polypeptide
Define ‘non-coding base sequences’ and describe where the non-coding multiple repeats are positioned in the genome. (2)
DNA that does not code for protein
Found between genes
Compare and contrast DNA in eukaryotic cells with DNA in prokaryotic cells.
- Identical nucleotide stucture
- Nucleotides joined by phosphodiester bonds
- Eurkayotic DNA linear, Prokaryotic DNA circular
- Eukaryotic DNA longer than Prokaryotic
- Eukaryotic DNA contains introns; prokaroytic DNA does not
- Eukaroytic DNA aassociated with histones; Prokaryotic DNA is noy
Suggest one way the structure of the chromosome could differ along its length to results in the stain binding more in some areas.
Difference in base sequences
Describe how one amino acid is added to a polypeptide that is being formed at a ribosome during translation. (3)
tRNA brings specific amino acid to ribosome
Anticodon binds to codon
Peptide bond formed between amino acids
What is the proteome of a cell?
Range of proteins a cell can produce
Starting with mRNA in the cytoplasm, describe how translation leads to the production of a polypeptide. (5)
Do not include descriptions of transcription and splicing in your answer
- mRNA attaches to ribosome
- Ribsome moves to start codon
- tRNA brings specific amino acid
- tRNA anticodon binds complementary to mRNA codon
- Ribosome moves along to next codon
- Ribosome forms peptide bonds between amino acids using ATP
Give the two components of a ribsome. (1)
rRNA
Protein
Describe how a phosphodiester bond is formed between two nucleotides within a DNA molecule. (3)
- Condensation reaction and loss of water
- Between phosphate and deoxyribose
- Catalysed by DNA polymerase
