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DNA Structure and replication
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DNA (deoxyribonucleic Acid) carries the genetic code. DNA Structure
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DNA (deoxyribonucleic Acid) carries the genetic code. Found in the chromosomes – it has a double helix shape (like a twisted ladder) DNA Structure
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DNA (deoxyribonucleic Acid) carries the genetic code. Found in the chromosomes – it has a double helix shape (like a twisted ladder) The side strands are made of alternating sugar and phosphate groups. DNA Structure
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DNA (deoxyribonucleic Acid) carries the genetic code. Found in the chromosomes – it has a double helix shape (like a twisted ladder) The side strands are made of alternating sugar and phosphate groups. The ‘rungs’ are made of paired nitrogenous bases. DNA Structure
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DNA (deoxyribonucleic Acid) carries the genetic code. Found in the chromosomes – it has a double helix shape (like a twisted ladder) The side strands are made of alternating sugar and phosphate groups. The ‘rungs’ are made of paired nitrogenous bases. Each strand of DNA is made of many repeating units called nucleotides (a sugar, a phosphate, and a nitrogen base) DNA Structure
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Nitrogen base (any one of A, T, C, G) Deoxyribose Sugar Phos phate
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A always pairs with T (adenine and thymine) C always pairs with G (cytosine and guanine) DNA Structure
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A always pairs with T (adenine and thymine) C always pairs with G (cytosine and guanine) The pairs are held together by weak hydrogen bonds – therefore holding the 2 strands of DNA together. DNA Structure
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A always pairs with T (adenine and thymine) C always pairs with G (cytosine and guanine) The pairs are held together by weak hydrogen bonds – therefore holding the 2 strands of DNA together. The genetic code is the sequence of bases along one strand – 3 bases = a triplet. DNA Structure
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A always pairs with T (adenine and thymine) C always pairs with G (cytosine and guanine) The pairs are held together by weak hydrogen bonds – therefore holding the 2 strands of DNA together. The genetic code is the sequence of bases along one strand – 3 bases = a triplet. A triplet codes for a particular amino acid, and amino acids together make proteins. DNA Structure
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All the triplets that code for one complete protein make up a gene. DNA Structure
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All the triplets that code for one complete protein make up a gene. Different sequences of bases along a gene can produce proteins that are slightly different (eg. One sequence would code for brown eyes, and one would code for blue) DNA Structure
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All the triplets that code for one complete protein make up a gene. Different sequences of bases along a gene can produce proteins that are slightly different (eg. One sequence would code for brown eyes, and one would code for blue) Different forms of a gene are called alleles. DNA Structure
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