Bio PTC PCR lab quiz Exam Latest
Update 2026 (Questions and Answers-
Verified solutions
gene TAS2R38 (ability to taste bitter substances) - CORRECT ANSWERS this lab allows
students to determine their phenotype & genotype for this gene
phenylthiocarbamide (PTC) - CORRECT ANSWERS Bitter substance that students will be
testing to see if they can taste
strongly - CORRECT ANSWERS A homozygous dominant student can taste the bitter
substance _____________
weakly - CORRECT ANSWERS A heterozygous student can taste the bitter substance
_____________
can't - CORRECT ANSWERS A homozygous recessive student ______ taste the bitter
substance
DNA extraction - CORRECT ANSWERS Release of DNA from nucleus and cell. Cheek cells
will be boiled to release the DNA and Chelex beads will bind to contaminants that interfere with the
polymerase chain reaction
Polymerase chain reaction (PCR) - CORRECT ANSWERS makes many copies of the PTC
gene. 3 main ingredients: primers, nucleotide bases, Taq DNA polymerase enzyme. Go through many
cycles of heating and cooling. 1st: heated to denature (open) the double-stranded DNA so the
nucleotides of each strand are exposed, 2nd: cooled=so primers anneal (stick) to single stranded DNA,
3rd: heated slightly + so PCR enzyme can extend the strand from the primers
Update 2026 (Questions and Answers-
Verified solutions
gene TAS2R38 (ability to taste bitter substances) - CORRECT ANSWERS this lab allows
students to determine their phenotype & genotype for this gene
phenylthiocarbamide (PTC) - CORRECT ANSWERS Bitter substance that students will be
testing to see if they can taste
strongly - CORRECT ANSWERS A homozygous dominant student can taste the bitter
substance _____________
weakly - CORRECT ANSWERS A heterozygous student can taste the bitter substance
_____________
can't - CORRECT ANSWERS A homozygous recessive student ______ taste the bitter
substance
DNA extraction - CORRECT ANSWERS Release of DNA from nucleus and cell. Cheek cells
will be boiled to release the DNA and Chelex beads will bind to contaminants that interfere with the
polymerase chain reaction
Polymerase chain reaction (PCR) - CORRECT ANSWERS makes many copies of the PTC
gene. 3 main ingredients: primers, nucleotide bases, Taq DNA polymerase enzyme. Go through many
cycles of heating and cooling. 1st: heated to denature (open) the double-stranded DNA so the
nucleotides of each strand are exposed, 2nd: cooled=so primers anneal (stick) to single stranded DNA,
3rd: heated slightly + so PCR enzyme can extend the strand from the primers
