Chapter 7 Test Flashcards
What is meant by a double helix?
It is a sort of twisted ladder where the sides consist of alternative sugar and phosphate molecules and the steps are made up of complementary nitrogen base pairs
Know what male and female chromosomes are
(X, Y) (X, X)
How do they determine the percentage of people having a particular allele?
It is the number of times an allele is observed in a given population divided by the total allele observed in the population.
How do you trace mtDNA through ancestry?
Mother, maternal side
Can two people have the same DNA?
Yes, identical twins have the same DNA
DNA can be recovered from what?
White blood cells, skin cells, semen, saliva, and hair
95% of noncoding DNA is involved in what
Some may be involved in cell regulation acting as genetic on-off switches, they do not code for proteins and are deleted once the DNA is read
What is meant by homozygous genotypes?
Homo Chromosome- both copies of a gene are identical in the pair
Homozygous genotype; If someone has two alleles that are the same for a specific STR (9, 9) (14, 14)
James Watson and Francis Crick Nobel prize in what?
For their work in describing the structure of DNA as a double helix
Which chromosomes have the same shape and the same genes?
Homologous chromosomes, autosomes
The DNA in a chromosome is called what?
Nuclear cell structure, nuclear DNA, and genes are a specific segment
Know what a short tandem repeat is
A sequence of repeating bases in noncoding regions of DNA that are used in DNA profiling
How many base pairs are in a human body?
Approximately 6 billion
Dr. Alec Jeffreys is known for what
Early DNA fingerprinting using gel electrophoresis. DNA is collected and extracted from a mouth swab from male villagers, added restriction enzymes cut the DNA into fragments, performed gel electrophoresis–restriction fragments are separated by size on a gel when an electric field is applied, radioactive probes bond to the highly variable regions creating a unique band pattern–compared DNA sequences of crime-scene evidence to suspect from village population.
Which method is used to identify different STR markers?
DNA is extracted from body tissues, fluorescent primers are added to amplify the STRs using PCR, DNA STR alleles are separated by size within capillary electrophoresis tubes, DNA samples pass through a laser, fluorescent dyes on DNA absorb and emit light, a prism separates different colors of light so that they strike an electronic detector at different locations, a signal is recorded as peaks in the graphic display (electropherogram), STR alleles are identified by size and color on the graphic display. Electrophoresis and electropherogram.
