Biotechnology

Question 1

What is does PCR stand for?

Answer 1

Polymerase Chain Reaction

Question 2

What are the steps involved in PCR?

Answer 2

• Denaturation
• Annealing
• Elongation

Remember 3 letters and three steps

Question 3

Can you descrbe the process of denaturation?

Answer 3

• Helicase separates the two strands of DNA to be copied
• Temperatures of approximately 94-96ºC to bek the hydrogen bonds
• This separates the strands but does not disrupt each individual strand

H96S: high on 96 to separate

Question 4

Can you describe the process of annealing?

Answer 4

• Annealing is when the temperature is decrease to 50-60ºC
• Short strands of DNA called primers bind to the single DNA strands
• Primers are complementary at the end of the DNA strand

primers need 60 to complement each other

Question 5

Can you describe the process of elongation?

Answer 5

• Similar to DNA transcription, taq polymerase joins new, complementary nucleotides
• continues section where the primer was placed
• Temperature rises to 72ºC, the optimal temperature of taq polymerase to start binding

taq polymerase loves 72

Question 6

Why is taq polymerase used during PCR?

Answer 6

• comes from the heat-loving bacterium, Thermus aquaticus
• does not denature when exposed to high heat, therefore it is preferrable

love the heat

Question 7

What is the function of gel electrophoresis?

Answer 7

• separate DNA strands based on their lenghts
• DNA is placed inside semi-solid gels, immersed in electrolyte solution
• DNA is negative and moves towards the positive electrode
• The larger the DNA strand, the slower it will travel.
• The results look similar to barcodes or ladders

SEPLL

Question 8

How are DNA ladders used to compare the sample DNA?

Answer 8

• the ladder contains DNA with the known lengths
• determine the length of DNA from the sample

Question 9

What is the purpose of a primer?

Answer 9

It used as a starting point for DNA synthesis.

the prime for time!

Question 10

What are the uses of gel electrophoresis?

Answer 10

• hereditary diseases
• paternity tests
• forensics/ crime scenes

Question 11

What is DNA sequencing?

Answer 11

• by comparing how DNA sequences change and mutations can be detected
• many diseases can be detected by this

e.g sickle cell anemia, cystic fibrosis, some cancers

NOTE: also used in paternity tests and compare species to track evolutionary changes.

Question 12

Ethical considerations involved with genetic information

Answer 12

Autonomy

Equity

Privacy

Confidentiality

Question 13

Define restriction enzyme

Answer 13

Enzymes that cut DNA across the double helix.
* each restriction enzyme has specific recognition site (DNA sequence) which it will cut.

Question 14

Define DNA sequencing

Answer 14

Determines the precise order of nucleotides (phosphate and sugar molecule with nitrogen base) in a sample of DNA.

Question 15

Describe comparative genomics

Answer 15

Comparative genomics is a new field of biological research in which the genome sequences of different species are compared.

Question 16

What is the result of comparing the genome of different species?

Answer 16

• provides effective means of studying evolutionary changes
• helping to identity preserved genes and those which give organisms their unique characteristics.

Question 17

Describe the sticky end restriction enzymes

Answer 17

• DNA cut is staggered
• Sticky end is a stretch of unpaired nucleotides overhanging
• exposed strand can only re-join to DNA with complimentary based pairs
• Can be from a different organism

STICKY IS GAY

Question 18

Describe the blunt end restriction enzymes

Answer 18

• no overhangs
• cuts straight across DNA
• terminates in base pair

BLUNT IS STRAIGHT

Question 19

How is bioinformatics useful?

Answer 19

• assist evolutionary biologist in tracing the evolution of a large number of organisms by measuring changes in DNA
• Done instead of traditional methods e.g., physical taxonomy, physiological observations
• recent development allows researchers to compare entire genomes.