RG- DNA,genes,chromosoes

• How is DNA stored in different organisms?

  DNA stored differently in different organisms
• What does DNA contain?

  genes
• What is a gene?

  A sequence of DNA bases that codes for either a polypeptide or functional RNA
• What forms the primary structure of a protein?

  The sequence of amino acids in a polypeptide
• What do different polypeptides have?

  A different number and order of amino acids.
• What does the order of bases in a gene determine?

  The order of amino acids in a particular polypeptide
• What is each amino acid coded for by?

  A sequence of three bases in a gene called a triplet
• How is a polypeptide made?

  • DNA is first copied into messenger RNA (mRNA)
  • This is the first stage of protein synthesis
• What do genes that do not code for a polypeptide code for instead?

  Functional RNA
• What is functional RNA?


  = RNA molecules other than mRNA, which perform special tasks during protein synthesis
• What is rRNA?

  Ribosomal RNA- forms part of ribosomes
• What is tRNA?

  Transfer RNA
• What is mRNA?

  messenger RNA
• What is a cell's genome?

  The complete set of genes in the cell
• What is a cell's proteome?


  The full range of proteins that the cell is able to produce
• What is DNA stored as in a eukaryotic cell nucleus?

  As chromosomes
• How many pairs of chromosomes do humans have?

  23
• How many chromosomes do humans have in total?

  46
• What are homologous pairs?

  Pairs of matching chromosomes
• Humans have 46 chromosomes in total - two number 1s, two number 2s
• What are chromosomes like in a homologous pair?

  Both chromosomes are the same size and have the same genes, although they could have different alleles
• Where will allels coding for the same characteristics be found?

  at the same fixed position (locus) on each chromosome in a homologous pair