DNA
How many base pairs are there in the human genome? How much of your DNA is coding DNA? How much of your DNA is the same as everyone else's?
3 billion base pairs 1% dna coding in dna 99.4% is identical to everyone else
Pyrimidines
Cytosine and Thymine
locus
Location of a gene on a chromosome
RFLP
Restriction Fragment Length Polymorphisms - Different fragment lengths of base pairs that result from cutting a DNA molecule with restriction enzymes.
2. Name at least 5 sources of DNA at a crime scene.
Semen Hair Saliva Urine Bone marrow
15. What is allele frequency and why is it important?
Shows the rate of an allele is present within a population
11. How should biological evidence be collected, packaged and preserved at a crime scene?
dry
Exon
expressed sequence of DNA; codes for a protein
PCR
(polymerase chain reaction) multiple copies of a specific segment of DNA
What is CODIS and how is it used? How many loci are tested?
-CODIS - links crimes and unsolved cases with repeat offenders -21 loci tested
13. What is the difference between a genome, a chromosome, a gene and an allele?
-Gene and allele is an allele is a variant form of the gene -Chromosome is contained unit of genes
. Give at least 4 reasons for DNA testing.
-Match to a suspect -Missing people -Convicted felon databases -Kidnapping
What is PCR? How many thermal cycles does it take to get 2 copies of the targeted DNA sequence? 22 copies? 1 billion copies?
-PCR : technique that makes multiple identical copies from trace amounts of DNA -3 cycles = 2 copies -5 cycles = 22 copies -32 cycles = 1 billion copies
16. What is an STR? How is it used in DNA analysis?
-Short Tandem Repeats -Determine # of repeats in each allele found in the DNA profile.
8. Explain how gel electrophoresis works. What charge does DNA have?
-Thick gel is used, loads DNA into gel wells, runs the gel, electric current runs through the gel to sort it by size. (smaller move further) -Negatively charged (DNA)
14. How many alleles are at each locus on a chromosome?
2 alleles
Diploid
2 sets of chromosomes
5. What is the base pairing rule?
A-T and C-G
Haploid
An organism or cell having only one complete set of chromosomes.
Autosome
Any chromosome that is not a sex chromosome
How many chromosomes are in each body cell? In each sex cell?
Chromosomes in each body - 46 Chromosomes in each sex cell - 23
restriction enzymes
Enzyme that cuts DNA at a specific sequence of nucleotides
Label the diagram using the following words: nucleic acid, phosphate group, sugar, backbone, double helix, hydrogen bond.
Nucleotides - C,G,A, and T Phosphate groups- circles Sugar - orange Backbone - orange Hydrogen bond - the red lines
6. Explain the difference between a chromosome, a gene and an allele.
chromosome - cell structure that contains genetic info along strands of DNA Gene - DNA sequences that have instructions that determine our inherited characteristics like blood type
Intron
sequence of DNA that is not involved in coding for a protein
Polymorphism
the individual differences of form among the members of a species