3/12 rubric outline

Question 1

What are the nitrogenous bases in DNA and how do they pair together?

Answer 1

Nitrogenous bases are thymine, guanine, adenine, and cytosine.
The base pairing rules are:
- Adenine and thymine
- Guanine and Cytosine

Question 2

What is a nucleotide

Answer 2

Nucleotides are the building blocks of DNA and RNA. They consist of three main components:
- A deoxyribose (DNA) or ribose (RNA) sugar
- A phosphate group
- A nitrogenous base (adenine, thymine or uracil, guanine, cytosine)

Question 3

What are the three main forms of RNA

Answer 3

three main forms of RNA are:
- mRNA (messenger RNA)
- rRNA (ribosomal RNA)
- tRNA (tranfer RNA)

Question 4

mRNA (messenger RNA)

Answer 4

Acts as a messenger by carrying genetic information from the nucleus to the ribosomes of the cell. It is made during transcription (a part of protein synthesis)

Question 5

rRNA (ribosomal RNA)

Answer 5

rRNA is made in the nucleus and combines with protein to make ribosomes. Ribosomes are organelles that synthesise proteins during translation.

Question 6

tRNA (transfer RNA)

Answer 6

RNA molecules that transfer amino acids from the nucleus to ribosomes to form part of a polypeptide chain. This takes place when tRNA and mRNA work together through codons in translation.

Question 7

What is a gene

Answer 7

A gene is a segment of DNA that codes for an organism’s characteristics/traits. It is passed down through heredity.

Question 8

What are the main components of a gene.

Answer 8

The main components of a gene are:
- Operator region
- Intron
- Extron
- Promoter region

Question 9

Intron

Answer 9

Segments of genes that don’t code for anything and are spliced out of the mRNA

Question 10

Extron

Answer 10

Segments of genes that code and are put together to form mature mRNA

Question 11

Promoter (gene)

Answer 11

The sequence of a gene that is recognised by RNA polymerase to undergo transcription.

Question 12

Operator (gene)

Answer 12

The sequence of a gene that represses the lac operon.

Question 13

What is the link between nucleic acids and proteins?

Answer 13

Nucleic acids carry genetic information which is read by different types of RNA through different processes to produce proteins for the body to function.
- Both nucleic acids and proteins are made up of smaller molecules to form chains
- DNA is made of nucleic acids and protein is amde of amino acids.

Question 14

DNA manipulation

Answer 14

Genetic engineering that uses biotechnology to directly manipulate the genetic information of an organism’s genome. The point is to improve or produce organisms with desirable traits.

Question 15

Ways of DNA manipulation

Answer 15

• Introducing new DNA
• Editing existing DNA

Question 16

DNA polymerase

Answer 16

Enzyme that works on DNA and needs atleast a double strand to make it work. An example of DNA polymerase is Taq polymeraseT

Question 17

Taq polymerase

Answer 17

DNA polymerase used in PCR

Question 18

reverse transcriptase

Answer 18

makes DNA from an RNA molecule

Question 19

How are blunt edges created in DNA?

Answer 19

Blunt edges are created when the restriction enzyme cuts the DNA directly opposite to each other. No overhangs

Question 20

How are sticky edges created in DNA?

Answer 20

Sticky edges are created when the restriction enzyme cuts the DNA at two different positions that aren’t directionally opposite. Overhangs.

Question 21

What are ligases and polymerases used for?a

Answer 21

Ligase and polyemerases are used to create and develop DNA by creating DNA strands and building phosphodiester bonds between them.

Question 22

Endonuclease / restriction enzyme

Answer 22

Cuts DNA at specific locations called recognition sites to allow scientists to study the gene.

Question 23

Ligase

Answer 23

Enzymes that cause the joining of DNA

Question 24

Polymerase

Answer 24

Enzymes that cause the synthesis (formation) of DNA

Question 25

PCR (polymerase chain reaction)

Answer 25

Makes copies of specific DNA sequences with the help of the polymerase enzyme.

Question 26

CRISPR Cas9

Answer 26

A gene in bacterial (prokaryotic) cells that is used as a genetic engineering tool to edit pieces of cells DNA with the help of guide RNA.

Question 27

gRNA (guide RNA)

Answer 27

a short sequence of RNA that is produced during transcription, that guides CRISPR-Cas9 to the segment of DNA that needs editing.

Question 28

Process of CRISPR Cas9 editing the genome.

Answer 28

1. Scientists observe the target gene and according to that make a guideRNA and Cas9 enzyme complex accordingly.
2. Cas9 complex identifies the target DNA and snips both strands off.
3. Scientists either
   a. insert a replacement gene/nucleotide and let the DNA repair mechanism add additional changes.
   b. Cell consists of repair mechanisms which add in nucleotides, causing mutations that disable the gene.

Question 29

What is the function of CRISPR-Cas9 in bacteria?

Answer 29

To get rid of the virus and split the DNA.

Question 30

Outline the potential uses for CRISPR-Cas9 in humans.

Answer 30

To cure:
- a range of genetic diseases
- cancer
- blood disorders

Question 31

How has the CRISPR-Cas9 system been used as a biological technique for gene editing in eukaryotes?

Answer 31

CRISPR-Cas9 has been used to evaluate and activate gene expression instead of cutting off the DNA. This technique allows researchers to study a gene’s function.

Question 32

How does gRNA and CRISPR-Cas9 work together?

Answer 32

gRNA is an RNA that consists of guide sequence domain at the 5’ end which is complementary to the DNA sequence end. gRNA binds to the CRISPR-Cas9 protein and guides it to the genome site for splitting

Question 33

splicing

Answer 33

A process where the extrons (coding regions or gene) are joined together to form mature RNA, eliminating the introns (non-coding regions)