week 5

Question 1

what does gel electrophoresis do?

Answer 1

separates pieces of DNA by molecular size and shape so they can be viewed and identified

Question 2

how does gel electrophoresis work?

Answer 2

electric field in the agarose gel means that negatively charged DNA will move toward the positive electrode
smaller molecules of DNA will move faster than larger molecules

Question 3

true or false: DNA is negatively charged

Answer 3

true - the negative charge of the phosphates in the DNA is useful in electrophoresis because the

Question 4

what is PCR?

Answer 4

polymerase chain reaction
it makes many copies of DNa from a single strand, and it only amplifies the human genome DNA pieces under examination to make it easily visible

Question 5

how does PCR work?

Answer 5

denaturation - DNA strands are separated by raising the temperature
annealing - primer binds to the DNA
extension - Taq polymerase enzyme isolates the necessary parts of the DNA

Question 6

what is the law of segregation?

Answer 6

pairs of homologous chromosomes separate in meiosis so that only one chromosome from each pair is present in each gamete

Question 7

chi square test

Answer 7

see if genes are assorted independently
look for ratios of 1:1:1:1 or 9:3:3:1

Question 8

steps for chi square value

Answer 8

(observed - expected)^2 / expected