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