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DNA and genes
Grade 6 science ziccardi
| Term | Definition |
|---|---|
| Chromosomes are made up of | protein and DNA |
| Gene material must carry | instructions for cell processes and cell structures |
| Nucleotides are | subunits of DNA |
| Nucleotides are made up of | a sugar a phosphate and a base |
| Gene material must be copied each time it reproduces so that each set contains the correct number of | chromosomes |
| Four | bases are contained in the nucleotides |
| Base pairs | adenine - thymine and guanine - cytosine |
| Guanine always matches up with | cytosine |
| Thymine always matches with | Adenine |
| Chargaff's Rule | the amount of cytosine = guanine and Adenine = Thymine |
| Rossiland Franklin used | x-ray diffraction to make images of DNA and discovered that it had a spiral shape. |
| Watson and crick | made a model of DNA that was a twisted ladder or double helix |
| DNA | Deoxyribonucleic Acid |
| Sides of the ladder are made up of | Alternating sugar and phosphate molecules |
| The old and new fraction of the DNA strand is | Half |
| DNA copies itself by | 1.Splits down the middle 2.Each half receives complementary bases to complete 2 strands |
| DNA is copied | Every time the cell divides |
| 3 important events that led to understanding of the DNA structure were' | Chargaff's Rule, Franklin's discovery, and Watson & Cricks model. |
| Watson and Crick | built a model of DNA. |
| A mutation is | Change in the nucleotide-base sequence of a gene or DNA molecule |
| The 3 types of mutations are' | Insertion, substitution, & deletion |
| The meaning of insertion | When an extra base is added |
| The meaning of deletion is | When a base is left out |
| The meaning of substitution is | When a wrong base is used |
| The most common base is | Substitution |
| The 3 possible consequences of changes in your DNA are' | Improved trait, no change, & harmful trait |
| Proteins correct | Errors on our DNA |
| Errors on our DNA often happen when | DNA is copied |
| A mutagen is | Any physical or chemical agent that can raise a mutation. |
| 4 mutagens are | high energy radiation on x-rays, high energy radiation from ultra violet radiation, asbestos, & chemicals in cigarette smoke. |