Chapter 11

Question 1

Nucleotides

Answer 1

consists of one of four bases (adenine, guanine, thymine, and cytosine) attached to a phosphate-sugar group

Question 2

DNA and Proteins

Answer 2

Nucleotides code for amino acids, which are combined into chains to create proteins

Question 3

Purpose of tandem repeats

Answer 3

fillers between coding regions

Question 4

DNA Replication

Answer 4

DNA unwinds from the double helix, then is exposed to free nucleotides, then nucleotides assemble in proper order (base pairing) and polymerases assemble new DNA strands

Question 5

PCR

Answer 5

heat DNA > add primer (short strand of DNA used to target site of replication) > add DNA polymerase and free nucleotides

Question 6

Advantage of PCR

Answer 6

copies and multiplies a DNA sample, solves problem of limited sample size

Question 7

STR

Answer 7

region of DNA containing short segments consisting of three to seven repeating base pairs; ideal for PCR replication

Question 8

Advantage of STR

Answer 8

less susceptible to degradation than regular DNA; multiplexing can detect more than one DNA marker in a single analysis

Question 9

YSTR

Answer 9

STR located on Y chromosome (amelogenin gene determined gender); only gives 1 band so it is easier to read than normal STRs; useful for cases involving more than one male

Question 10

Mitochondrial DNA

Answer 10

contains maternally inherited DNA; supplies energy to the cell, much more plentiful than nuclear DNA; found in skeletal remains; does not discriminate as well as STRs; first admitted in Tennessee vs. Paul Ware

Question 11

Preservation of evidence

Answer 11

standard/reference samples should be obtained, bodily fluids must be assumed to be infectious, each article should be packaged separately in paper bag

Question 12

Substrate Control

Answer 12

swabbing an unstained object adjacent to an area on which biological material has been deposited to determine if it was the stain or the actual material