AQA A Level Biology DNA, genes and protein synthesis Practice Questions with answers

AQA A Level Biology DNA, genes and protein synthesis Practice Questions with answers What does a gene do? - correct answerscodes for amino acid sequence of polypeptide, codes for RNA (rRNA & tRNA) give 6 features of the genetic code - correct answersknown as 'degenerate code' as most amino acids coded for by multiple triplets, triplet read in one direction across DNA strand, always starts with starts with same triplet, three triplets act as 'stop codes', code is non-overlapping (each base sequence read once), code is universal in all organisms (few minor exceptions) What is an exon? - correct answerssequence that codes for amino acids What is an intron? - correct answerssequence that doesn't code for an amino acid give the differences in a eukaryotic cells DNA and a prokaryotic cells DNA - correct answersp: DNA molecules shorter, form circle, not associated with proteins, no chromosomes. e: DNA molecules longer, linear, associate with histones to form chromosomes what is a homologous pair of chromosomes? - correct answers1 maternal (from mother), 1 paternal (from father), same genes but different alleles what is the diploid number of chromosomes? - correct answers46 (23 pairs) What is a mutation? - correct answerschange in base sequence, produces new allele What is a codon? - correct answersa three base sequence that codes for an amino acid what is a genome? - correct answersThe complete set of an organism's genes what is a proteome? - correct answersfull range of proteins produced by the genome give the structure of RNA - correct answers(pentose) ribose sugar, A G C U, phosphate group