forensics

Question 1

test for human blood?

Answer 1

1. collect a sample
2. add a drop of phenolphthalein to the sample
3. after a few seconds, add a drop of hydrogen peroxide
4. if the substance goes pink immediately, blood is present

Question 2

how can blood typing be used to solve crimes?

Answer 2

if the blood sample found at the crime scene does not match that of a suspect, the suspect can be ruled out.

Question 3

what are surface antigens?

Answer 3

surface antigens are sell markers that help scientists identify organisms.

Question 4

why are blood types important during transfusions?

Answer 4

if someone is given blood from a blood type that is not compatible with theirs, the blood can start to clump inside of their body. this can be fatal

Question 5

how do you make a microscope slide for fibres?

Answer 5

1. place a drop of water on the slide
2. place the fibre on the slide
3. place a coverslip over this
4. put on the stage and observe using a microscope

Question 6

origin and method of producing wool?

Answer 6

origin: sheep
method of producing: sheering sheep

Question 7

origin and method of producing cotton?

Answer 7

origin: derived from fibres surrounding cotton plants
method of producing: picking off of the plants

Question 8

origin and method of producing silk?

Answer 8

origin: silkworms
method of producing: collected from when silkworms spin the silk around plants

Question 9

what is gel electrophoresis?

Answer 9

gel electrophoresis is the method of separating mixtures of DNA

Question 10

what is the test for fingerprints?

Answer 10

dust a surface with a very fine powder, the oily residue from a fingerprint will pick up the dust.