Lab3: Bitter Gene

Question 1

What is the internal process when tasting bitter?

Answer 1

PTC(bitter substance) binds to TAS2R38 receptor — triggers a nerve signal to the brain

Question 2

If you have a mutation version of TAS2R38 gene can we taster bitter?

Answer 2

No

Question 3

Where is located the TAS2R38 gene mutation?

Answer 3

On chromosome 7

Question 4

What is the recessive and dominant allele in this experiment?

Answer 4

Recessive= t
Dominant =T

Question 5

What is an allele?

Answer 5

An alternative version of gene

Question 6

What is a phenotype?

Answer 6

Physical manifestation of the genotype (Taster or Non-taster)

Question 7

What is the type of mutation when your a non-taster

Answer 7

Substituation

Question 8

Give me the genotypes of a homozygote dominant

Answer 8

TT

Question 9

Where does the substitution occurs in non-taster of PTC?

Answer 9

On base pair 145 affects amino acid #49

Question 10

What is the function of PCR?

Answer 10

To amplify specific piece of DNA — amplifying gene of interest

Question 11

What is the function of lysis buffer?

Answer 11

Breaks down the cells

Question 12

What are dNTPs and what is its function?

Answer 12

Their free nucleotides that can attach to the primer to start the coding

Question 13

What is the function of taq polymerase?

Answer 13

Synthesize complementary strand of DNA

Question 14

Why do we use taq polymerase instead of DNA pol III in PCR?

Answer 14

Since taq polymerase is more efficient at high temperature

Question 15

What is the function of DNA primer?

Answer 15

To bind to complementarily to the start of TAS2R38 and tells taq pol where to start replication

Question 16

What are the 3 main step of PCR?

Answer 16

1)Dénaturation (heating — separating the two strands)
2)Annealing (cooling down — primer anneal to the DNA strand)
3)DNA synthesis (taq pol synthesis new strand)

Question 17

What is the function of protease?

Answer 17

Break down protein

Question 18

What is the function of ribonuclease?

Answer 18

Break down RNA

Question 19

What is the function of gel electrophoresis?

Answer 19

Séparâtes molecules on the basis of their size (base pair length) using their charge

Question 20

What is the charge of nucleic acids?

Answer 20

Négative

Question 21

What structure of nucleic acids are negative?

Answer 21

Phosphate group

Question 22

Does smaller molecules moves faster or slower than larger molecules through the gel?

Answer 22

Faster

Question 23

Since nucleic acids are negative they are pulled towards …

Answer 23

Positive anode electrode

Question 24

What is the function of the endonuclease restriction enzyme?

Answer 24

To detect SNP of the TAS2R38 gene and cuts the DNA at a specific sequence

Question 25

What is the name of the restriction enzyme we used in the experiment?

Answer 25

Haelll

Question 26

What is the only sequence that Haelll recognize?

Answer 26

GGCC in the functional TAS2R38

Question 27

When Haelll restriction enzyme recongnize the good sequence what it does to it?

Answer 27

Cut into smaller fragments — goes rapidly through the gel

Question 28

Why does Haelll doesn’t recognize the mutation and non-functional TAS2R38 allele?

Answer 28

Cause it has a GGGC sequence can’t be cut by the enzyme

Question 29

Why does the mutated and non-functional TAS2R38 allele can’t pass easily through the gel?

Answer 29

Because it wasn’t cut by the enzyme

Question 30

Where is the positive electrode in DNA electrophoresis?

Answer 30

Far end of the gel

Question 31

What is the function of the loading dye?

Answer 31

Permit to judge when to stop electrophoresis — before DNA strand exit the gel

Question 32

Is the loading dye used to stain and visualise the DNA?

Answer 32

NO

Question 33

What type of dye is added directly to the agarose gel?

Answer 33

Sybr safe stain

Question 34

What is the role of Sybr safe stain?

Answer 34

To bind to DNA during migration through the gel and makes DNA fluorescence when excited to UV light

Question 35

What is the function of the negative control for the restriction enzyme?

Answer 35

Check if the restriction enzyme worked properly

Question 36

What is the function of a DNA ladder?

Answer 36

-calibrate the size of the bands in bp’s -identify the sizes of the fragments that we have generated

Question 37

What are SNP?

Answer 37

Single nucleotide polymorphism

Question 38

During the experiment what was affected by SNP’s?

Answer 38

Restriction enzyme — Hae III

Question 39

What sequence does the Hae III recognize and don’t recognize

Answer 39

Recognize: GGCC Don’t recognize: GGGC

Question 40

Why doe we use heat in this lab?è

Answer 40

To break hydrogen bonds between the two strands

Question 41

What is a DNA ladder?

Answer 41

A way to identify the sizes of the fragments that we have generated

Question 42

RFLP is a form of what?

Answer 42

DNA profiling