6.1 Forensic biology Flashcards
what are four ways the police can identify a body?
documents on the person, fingerprinting, dental records and DNA profiling
What are introns?
sections of DNA that don’t code for a protein
what are short tandem repeats (STRs)?
Repeated sections within introns
how is a DNA sample obtained?
from almost all biological tissue
what technique is used to separate DNA fragments?
gel electrophoresis
what affects how far the DNA fragments move?
their charge and size
what are the three temperatures in PCR?
95 degrees celsius
55 degrees celsius
70 degrees celsius
what is a normal human core body temperature?
36.2 - 37.6
what happens as soon as a person dies and why?
their body cools down as exothermic reactions stop
when is body temperature a useful measurement?
the first 24 hours post-mortem
how long does it take for a body to complete rigor mortis?
6-9 hours
what is lysozyme and what does it do?
an enzyme that kills bacteria by breaking down their cell wall
what triggers the inflammatory response?
invading microbes from a cut
what are the effects of histamine?
arterioles in the area dilate and increase the permeability of the capillaries
what is oedema?
swelling caused by plasma fluid, white blood cells and antibodies leaking from the blood into the tissue
what are phagocytes?
White blood cells that engulf bacteria and other foreign matter in the blood and tissues
what types of white blood cells are phagocytes?
neutrophils and macrophages
what is pus?
Dead cells, mainly neutrophils, that form a thick fluid
what is interferon and how does it work?
a protein produced by microbe-infected cells, it prevents microbes from multiplying by inhibiting microbial protein synthesis
