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U3 AO2 Flashcards

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1
Q

What is a protein?

A

A protein is a biomacromocule made up of amino acid monomers folded into 3d shape

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2
Q

What is a polypeptide?

A

Polymer made up of amino acid monomers

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3
Q

What does the proteome refer to?

A

All the proteins expressed within an organism

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4
Q

Name examples of protein function

A

Enzyme:Catalyse Enzymes:Enzymes are catalysts meaning they speed up chemical reactions without using themselves up (examples include; Amylase,RNA polymerase and Catalase)

Transport:Transport proteins are typically embedded in membranes,controlling entry and exit from the cell (glucose channels,chloride-channels)

Structural:Structural proteins support cell and tissue shape (Keratin,Elastin)

Hormones:Hormones proteins are chemical messengers used to communicate and induce changes in cells (insulin,Adrenline)

Receptors: Receptor proteins recieve signals from their environment (Hormone receptors)

Defence:Defence proteins are involved within the immune system,recognising and destroying pathogens. (Antibodies,compliment proteins)

Motor/contractile proteins:Proteins involved in the contraction and movement of mosucles. (kinesin)

Storage:Storage proteins act as reserves for metal ions and other organisms throughout a molecule

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5
Q

What bonds hold amino acids together?

A

Peptide bonds formed via a condensation polymerisation reaction

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6
Q

where does the joining of amino acids occur?

A

At the ribosome during translation

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7
Q

Draw an amino acid

A

NH2——-C———-COOH
|
R

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8
Q

What does the R group do

A

Determines the function of the amino acid, and its folding.

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9
Q

What makes proteins so functionally diverse

A

The functional diversity of proteins is due to there number of combinations that r groups and amino acids interact with each other and are able to fold into different polypeptides.

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10
Q

Primary Protein structure:

A

the order of nucleotides/ the sequence of amino acids making up a polypeptide chain

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11
Q

Secondary Protein structure:

A

The formation of alpha helix and beta pleated sheats.

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12
Q

Teteriary structure:

A

The functional 3d shape of a polypeptide (Disulphide bonds are strong covalent bonds that can form between 2 sulphur atoms (in the r group),further stabilising the protein structure)

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13
Q

Quaternary structure:

A

Functional 3d shape of a protein containing 2 or more polypeptides. (Polypeptide chains with tetiary structure that have a prosthetic group attached, a non-protein group attatched to protein are considered to create quaternery structure)

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14
Q

Nucleic acids

A

Polymer made up of nucleotide monomers, examples include DNA and RNA

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15
Q

What bonds hold together nucleic acids

A

Phosphodiester bonds formed via a condensation polymerisation reaction

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16
Q

What is a condensation polymerisation reaction?

A

Reaction between 2 monomers forming a larger polymer product releasing water as a bypass, an endothermic reaction taking in energy

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17
Q

What direction is DNA read in

A

5’-3’

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18
Q

Genome

A

All the genes within an organism

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19
Q

Describe DNA structure

A

DNA is composed of 2 strands that run antiparallel to eachother joined together by phospohodiester bonds formed via a condensation polymerisation reaction.These 2 chains are joined together by the conjugate base pairing of complementary nucletodies held together by hydrogen bonds.

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20
Q

mRNA (Messenger mRNA)

A

-carries genetic information from nucleus to ribosome during protein synthesis

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21
Q

tRNA (Transfer RNA)

A

-Brings complementary anti-codons and specific amino acids to ribosome during protein synthesis

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22
Q

rRNA

A

-Serves as the main structural component within cells

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23
Q

Differences of RNA to DNA

A

RNA compared to DNA contains uracil rather than thymine and contains a ribose sugar rather than deoxyrybose, it is also rather single stranded than double.

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24
Q

What is the genetic code

A

series of rules that determine how genetic information is transcribed and translated into functional proteins.Protein synthesis is determined by the genetic code

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25
Q

Universal:

A

The idea that all living organisms use the same codons to form the same amino acids

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26
Q

Unambigious:

A

Each codon can only code for 1 amino acid

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27
Q

Degenerate or redudant:

A

1 amino acid can be coded for by a range of different codons

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28
Q

Non overlapping:

A

Each codon is read in groups of 3 seperate to other amino acids.

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29
Q

Regulator genes-

A

produce proteins that control the action of other genes,Turn them on and off (repressor proteins).

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30
Q

Structural genes-

A

Produce proteins that become part of the structure and the functioning of the organism for example keratin

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31
Q

What does the promoter region of the gene do

A

The promoter region is an upstream (5’ end) binding site for RNA polymerase during transcription.Therefore the promoter region effectively denotes the starting position and direction of transcription.

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32
Q

What are introns

A

Non-coding regions of DNA that are removed during RNA processing.Introns can only be found in Eukaryotes.

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33
Q

What are exons

A

Exons are the coding regions of DNA which are transcribed and then translated to form the final protein.Found in both eukaryotes and prokaryotes.

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34
Q

Termination sequence

A

Represents a sequence of DNA that signals for the end of transcription

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35
Q

What is the operator region?

A

The operator region serves as binding site for repressor proteins which can then inhibit gene expression.This region is typically only found in prokaryotes.

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36
Q

What is the leader region?

A

The leader region is the section of DNA just upstream of the coding region and downstream of the promoter and operator.Leader region plays a critical role in the gene regulation via attenuation.

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37
Q

What does gene expression mean?

A

Gene expression is the process of reading stored information within a gene to create a functional,structural protein.

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38
Q

What is transcription?

A

Process of which a section of DNA is coded producing a mRNA molecule

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39
Q

Write the process of transcription including RNA processing

A
  1. Occurring in the nucleus(in Eukaryotes) in cytoplasm (in bacteria), DNA helicase unzips DNA, and RNA Polymerase binds to the promoter region initiating transcription
    1. RNA Polymerase runs along template strand in a 3’-5’ direction building a complementary template strand in a 5’-3’ direction, stopping once its hits a stop codon(UAG,UGA,UAA) falling off, leaving us with Pre-mRNA.
    (RNA processesing,occurs only in Eukaryotes)
    3.Methyl-g cap is added to the 5’ prime end of Pre-mRNA molecule and a poly-a-tail is added to the 3’ prime end
  2. Spliceosomes cut out introns and splice together exons leaving us with m-RNA.
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40
Q

What is translation?

A

Process by which mRNA sequence is read to produce corresponding amino acid sequence to build a polypeptide.

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41
Q

What is the process of translation

A

Intiation
-The 5’ end of the mRNA molecule binds to the ribosome and is read until the start codon (AUG) is recognised.Then a tRNA molecule with a complementary anti codon (UAC) binds to the ribosome and delivers the amino acid methionine,signifying the start of translation

Elongation-
After the first amino acid attaches, the mRNA molecule is fed through the ribosome so the next codon can be matches to its complementary tRNA anti-codon.Then complementary tRNA molecules deliver specfic amino acids to the ribosome, which bind to adjacent amino acids with a peptide bond via a condensation reaction.The first tRNA molecule then leaves the ribosome and continues to piock up amino acids, growing the amino acid chain

Termination-Linking of amino acids in the polypeptide chain continues until the ribosome raches a stop codon.The stop codons signals the end of translation/POlypeptide chain is then released by the ribosome into the cytosol or endoplasmic recticulum.

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42
Q

What are DNA binding proteins

A

bind to regions of nuclear DNA near genes and directly switch these genes on or off.These proteins carry a net positive charge that enables them to bind to DNA, which has a set net negative charge

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43
Q

What are signalling proteins

A

bind to receptors on the membrane of cells in their target tissue and trigger a series of interculllar reactions that switch genes on or off

44
Q

What is gene regulation?

A

Gene regulation involves the process of either activating or inhibiting a gene.By doing so an organism can conserve energy by reducing its need to make unnecessary products.

45
Q

What is the trp operon

A

-Trp operon contains a series of structural genes coding for tryptophan (trpE,trpD,trpC,trpB,and trpA) which there expression is controlled by a common promoter and operator.

46
Q

What happens when tryptophan levels are high

A

1.To regulate the expression of Tryptophan structural genes, the regulatory gene for trp operon is constantly expressed, producing a repressor protein

2.when levels of tryptophan are high meaning they are present. Tryptophan is able to bind with the repressor protein inducing a confromational change (physical change) in the repressor, allowing it to bind to the operator region.

3.This allows the repressor protein to bind to the operator region

4.Acting as a block, the repressor protein inhibits the transcription of the tryptophan structural genes by RNA polymerase, inhibiting the unnecessary production of tryptophan.

47
Q

What happens when tryptophan levels are low

A

1.When Trypophan levels are low, there is not enough tryptophan molecules present that are able to consistently bind to the repressor protein,causing it too detach from the operator region.

3.This allows RNA polymerase to transcribe the trp structural genes so that level of tryptophan can increase

4.However, as tryptophan accumaltes in the cell it will once again bind the repressor protein slowly stopping transcritption of the trp structural genes

5.Together, these mechanisms keep the amount of tryptophan available at a relatively constant level to ensure that energy and resources are expended appropriately.

48
Q

Attenuation of trp operon when tryptophan levels are high

A
  1. Ribosome runs past the Tryptophan codons present in region 1 of the gene (since tryptophan is present)however, pauses between region 1 and 2 due to a stop codon

2.This prevents region 1 from binding with 2 and forces region 3 to bind with 4, forming a “hairpin loop”

3.This puts tension on the weak attenuator region (Due to adenine and thymine 2 weak hydrogen bonds), and mrna strand is forced too pull away ending transcription

49
Q

Attenuation of trp operon when tryptophan levels are low

A

1.Ribosome pauses at the 2 tryptophan codons in region 1 waiting for a tRNA molecule to bring tryptophan amino acid.

2.This allows 2 to pair with 3 preventing 3 and 4 from pairing with each other

3.while this creates a hairpin loop,its too far away from the attenuator region and therefore mrna doesn’t pull away and the ribosome continues transcribing the genes, creating more tryptophan

50
Q

What is exocytosis?

A

Exocytosis is the process by which the contents of a vesicle are released from a cell.Exocytosis is used to transport large substances such as proteins our of the cell that cannot just diffuse out the plasma membrane.Exocytosis is a form of bulk transport (active transport), this means that the process of exocytosis requires an input of energy via ATP moving from high to low gradients.

51
Q

Stages of exocytosis

A

1.A vesicle containing secretory products is transported to the plasma membrane
2.the membrane of vesicle fuses with the plasma membrane
3.the secretory products are released from the cell into the extracellular environment

52
Q

What is the full process of exocytosis

A

1.Proteins intended for secretion are synthesised at the ribosomes found on the Rough Endoplasmic reticulum.

2.They are then folded at the Rough ER and are transported to the golgi aparatus, via transport vesiciles.

3.At the Golgi apparatus, the proteins are modified before being packaged into secretory vesicles.

4.These secretory vesicles fuse with the plasma membrane, releasing the proteins into the extracellular environment via the process of exocytosis.

53
Q

What is the role of the ribosome in exocytosis

A

The ribosomes are the site of protein synthesis.Proteins intended for transport are synthesised on the ribosomes found on the rough ER.

54
Q

What is the role of the Rough ER in exocytosis

A

Folds and transports proteins

55
Q

role of transport vesicle in exocytosis

A

Transports proteins to the golgi aparatus.Fuses with the golgi membrane and releases its contents into the lumen.

56
Q

Describe the form and role of Golgi aparatus in exocytosis

A

Modifies and packages proteins, into secretory vesicles.The golgi aparatus is made up of 4-8 flattened membrane stacks called cisternae.After going through cis—–medial——to trans they then leave in vesicles that then get moved out to the plasma membrane and are secreted.As they move through they get modifeid by resident enzymes, this informs where the cells are going.

57
Q

Role of Secretory vesicles in exocytosis

A

Transports proteins to the plasma membrane for exocytosis

58
Q

What are enzymes?

A

Enzymes are catalysts, that lower the activation energy
(energy needed to start a chemical reaction) of a reaction,helping speed up chemical reactions without themselves being used up.Enzymes react with substrates.

59
Q

What does enzyme absolute or substrate specificity refer too?

A

The fact an enzyme can only act on one substrate

60
Q

What does enzyme bond specificity refer too?

A

The fact an enzyme can only act on 1 kind of chemical bond.

61
Q

What does enzyme group specificity refer too?

A

That an enzyme can only act on molecules with particular functional group(s) surronding a bond.

62
Q

Where does the substrate bind to on an enzyme?

A

Each enzyme has an active site in which the substrate kind bind to, to form enzyme catalysed reactions.When a substrate binds to the enzymes ative site, the active site undergoes a conformational change, with an enzyme-substrate complex being formed.

63
Q

The effect of temperature on an enzyme

A

-Enzymes work best at their optimal temperature
-As temperature increases enzymes gain kinetic energy and therefore enzyme-substrate collisions are increased,increasing the rate of reaction,however if it is too hot the enzyme risks being denatured
-If the temperature is too cold then enzymes are inactive

64
Q

The effect of pH on an enzyme

A

-Enzymes work best at their optimal pH
-Denaturation can occur if the pH is both too high or to low

65
Q

The effect of enzyme and substrate concentration

A

-High concentration of enzymes, increases the reaction rate
-However if substrate concentration is too high then all the active sites on the enzymes will be occupated and the reaction rate will not increase due to subtrate saturation.

66
Q

What does an enzyme limiting factor refer too?

A

It is a factor preventing an increased reaction rate,if the limiting factor is a reactant we call it an limiting regeant.

67
Q

What is enzyme competitive inhibition?

A

occurs when an inhibitor molecule binds to enzyme active site preventing substrate from binding.In order to block an active site, a competitive inhibitor has a shape complementary to the active site in some way.

68
Q

What is non-competitive enzyme inhibition?

A

-where inhibitor binds to allosteric site(not the active site) causing a conformational change in the active site of enzyme so subtrate can no longer bind

69
Q

What is reversible enzyme inhibition?

A

Enzymes are not permanently inhibited or damged, Reversible inhibitors inactivate enzymes through non-covalent interactions.Can be reversed by increasing the amount of substrate present.

70
Q

What is irreversible enzyme inhibition?

A

Covalently bonded, alters the structure of the enzyme (causing a conformational change) affecting its active site,This permamnently inhibits the enzyme beause the injibitior-enzyme bond is so strong that the inhibition cannot be reversed by the addition of excess substrate.

71
Q

What is gene editing

A

Process by which precise and targeted changes to the DNA sequence of genes can be achieved

72
Q

What is an endonuclease

A

refer to a broad range of enzymes responsible for cutting strands of dna.When these endonucleases target recognition sites they are known as recognition endonucleases.They cut the dna by breaking phosphodiester bonds of the sugar phosphate backbone holding the dna together.

73
Q

What kind of ends can endonucleases create

A

Blunt ends:Cut DNA by endonucleases with no overhanging nucleotides

Sticky end:Cut DNA by endonucleases resulting in overhanging nucleotides.Sticky ends are advnatagous in the sense they ensure genes are inserted correctly when manipulating DNA.

74
Q

What are Polymerases

A

polymerases Add nucleotides in the form of DNA or RNA,leading to the ability to copy entire genes,Polymerases synthesis polymer chains from monomer building blocks.

75
Q

DNA polymerase

A

typically used in the amplification or replication of DNA,however in order for polymerase to bind a primer must be present.

76
Q

What is CRISPR

A

is a naturally occuring sequence of DNA found in bacteria,playing an impoerant role in the attack against viruses in prokaryotic organisms

77
Q

What does CRISPR stand for

A

Clustered,regulatory,Interspaced,Short,Palindromic,Repeats

78
Q

CRISPR-Cas9 process

A

1.Bacteriophague injects its viral DNA into bacterium,with cas 1 and cas 2 (endonuclease, enzyme that cuts DNA)cutting out the PAM sequence(protospacer region) of viral DNA.

2.This Pam region then gets inserted between the repeater regions of the CRISPR sequence and is transcribed,becoming guide RNA

3.gRNA attaches to cas9 (endonuclease) which forms a Crisper-cas 9 complex.This is Guided to attack any renterring viral DNA since it has a complementary sequence.

4.The next time viral DNA enters the bacterium, The CRISPR cas-9 complex identifies the viral DNA and the cas 9 cuts sugar phosphate backbone of the viral dna, inactivating the virus.

79
Q

What types of gRNA are there

A

crRNA:made up of a spacer and a repeat region which are transcribed and cleaved producing the mugshot.

Tracer RNA:complementary sequence to crRNA which enables the 2 molecules to bond and establish final grna structure

80
Q

CRISPR-Cas9 in gene technology

A

-synthetic grna is made in a lab containing complementary sequences to the target gene scientists wish to cut, a Cas9 with appropriate pam sequence is identified
-synthetic grna is mixed with cas 9 to form CRISPR-CAS9 complex ,this formation is injected into a specific cell such a s a zygote
-cas9 finds target pam sequence and using grna, checks to make sure it has complementary seuqnce
-Cas 9 works and cuts at the restriction sites leaving blunt ends
-Scientists can introduce new nucleotides hoping it will ligate back into the DNA
-DNA attempts to ligate back together

81
Q

What does the polymerase chain reaction do

A

amplifies a sample of DNA by creating additional copies.

82
Q

What is required for PCR to occur

A

DNA sample: that subsequently gets denatured and amplified through the polymerase chain reaction

Taq polymerase: is required in the elongation stage to bind complementary nucleotides to the single-stranded DNA,Useful because it can survive at high temperatures and is useful as it doesnt break down at the high temperatures used in PCR.

nucleotide bases: must be constantly available for Taq polymerase to create a new strand that is complementary to the single-stranded DNA

Sequence-specific DNA primers: join to the 3’ end of single-stranded DNA by complementary base pairing to form the first segment of double-stranded DNA, allowing Taq polymerase to attach and begin extending the DNA strand.

83
Q

Process of PCR

A

Denaturation-
DNA is heated to approximately 90-95c to break the hydrogen bonds between the bases to seperate the strands,forming a single stranded DNA.

Annealing- The single stranded DNA is cooled to approximently 50-55c to allow the primers to bind to cpmplementary sequences on the single-stranded DNA

Elongation-The DNA is heated again back to 72c which allows taq polymerase to work optimally.Taq polymerase binds to the primer which acts as a starting point and begins synthesising a new complemntary strand of DNA

Repateing- steps 1-3 are repeated multiple times to create more copies of DNA

84
Q

What is gel electrophoresis?

A

-the process of sorting DNA fragments by their length

85
Q

Gel electrophoresis process

A

Steps in gel electrophoresis
1.Dna is cut by restriction endonucleases or a short sequence of DNA has been amplifieid during PCR

2.DNA samples are placed in welles in aragose gel (Negative side),The aragose gel has tiny pores that allow gel to pass.The aragose gel has been immersed in bueffer and as ion rich which allows an electrical current to pass through, a standard ladder is also added to determine length

3.An electrical current one positive and on enegative is passed through Gel.Since DNA has a negative charge )due to phosphate backbone), it moves towards the positive end

4.Smaller DNA fragments move faster through the Gel and travel further than larger fragments, after a few hours current is switched off , as DNA fragments stop moving they settle into bands

5.DNA is difficult to see so its stained with a florouscent dye such as ethidium bromise which allows bands to be viewed under UV lamp
Steps in gel electrophoresis
1.Dna is cut by restriction endonucleases or a short sequence of DNA has been amplifieid during PCR

2.DNA samples are placed in welles in aragose gel (Negative side),The aragose gel has tiny pores that allow gel to pass.The aragose gel has been immersed in bueffer and as ion rich which allows an electrical current to pass through, a standard ladder is also added to determine length

3.An electrical current one positive and on enegative is passed through Gel.Since DNA has a negative charge )due to phosphate backbone), it moves towards the positive end

4.Smaller DNA fragments move faster through the Gel and travel further than larger fragments, after a few hours current is switched off , as DNA fragments stop moving they settle into bands

5.DNA is difficult to see so its stained with a florouscent dye such as ethidium bromise which allows bands to be viewed under UV lamp

85
Q

What is bacterial transformation?

A

Process by which bacteria take up foreign DNA from their environment

85
Q

What is a recombinant plasmid?

A

circular DNA vector that is edited to contain a gene of interest (target gene)

86
Q

What does the gene of interest refer too?

A

A gene scientists want to be expressed in a recombinant bacteria.

87
Q

what do Selected marker genes/reporter genes do?

A

gene with an easily identificable phenotype, that can be used to identify wether a plasmid has taken up the gene of interest.Often resistance to antibiotics

88
Q

What is a plasmid

A

a small, circular loop of DNA separate from the chromosome, typically found in bacteria.

89
Q

What is a plasmid vector

A

piece of circular DNA,modified to be the ideal vector for bacterial transformation experiments

90
Q

What is the origin of replication (ORI)

A

A sequence found in prokaryotes that signals the start site of DNA replication

91
Q

What does vector refer too

A

means of introducing foreign DNA into organisms, plasmids are a popular vector in bacterial transformation.

92
Q

what does recombination mean?

A

The joining of DNA from different sources

93
Q

What does transformation in bacteria mean?

A

Changing a bacterium by introducing a plasmid into it

94
Q

What is required for scientists to make recombinant plasmids?

A

-Gene of interest (whats being inserted into the plasmid
-Plasmid vector
-restriction endonuclease (will cut gene of interest and plasmid)
-DNA ligase

95
Q

How to make recombinant plasmids

A
  1. Gene of interest is identified and isolated (sometimes copied using PCR)

-The Gene of interest cannot have introns prior to insertion,since prokaryotes dont have introns and therefore bacteria wouldn’t know what to do with intron segments,Introns are typically excluded from the gene of interest via two different methods; synthetic DNA, which is made in a lab by scientists without introns and cDNA (copy DNA) which is made by a an enzyme called reverse transcription which functions to transcribe mRNA backwards into cDNA

  1. Plasmid vector is selected into which gene of interest will be inserted

Plasmid vectors contain 3 essential parts
- Antibiotic resistance genes- (e.g ampR,tetA) This antibiotic resisitance that the plasmid vector allows it too be seen even after the antibiotic is added to the recombinant plasmid later on
- Origin of replication (ORI)-Sequence that signals the start site for DNA replication in bacteria
- Reporter gene- Genes that have an easily indetifiable phenotype, that a

  1. DNA of plasmid is cut at one point by restriction endonucleases, that create sticky ends, This changes the form from circular to linear.
  2. The gene of interest is then cut using the same restriction endonucleases that cut the plasmid, too ensure that the plasmid and gene of interest have complementary sticky ends
  3. The gene of interest (Foreign DNA fragments) and plasmids are then mixed and in some cases, their sticky ends pair by weak hydrogen bonds, the complex is now a recombinant plasmid
  4. The plasmid may not accept the pairing and therefore just reseal without the foreign DNA transforming back to just a plasmid, however if the Plasmid accepts,Ligase is added and this makes the joining permanent through covalent bonding.

antibiotics can be used to identify whether a plasmid has taken up the gene of interest

96
Q

How to encourage a plasmid to accept an inserted gene?

A

Heat shock:Using temperature to increase permiability of plasmid membrane:
1. Bacterial culture,recombinant plasmid and an antibacterial resistant allele are placed into ice back
2. The bacteria and plasmid is then heat shocked by being placed into hot water causing the plasma membrane cells to alter and become more permeable increasing the chance of the cell uptaking the plasmid.
3. The mix is then returned to ice bath to return plasma membrane to natural state
4. The bacteria is then plated on a agar plate along with antibiotic (i.e tetracyline) this is then incubated at 38c overnight.
5. Bacteria that have no taken up the plasmids will be killed by the antibiotics but bacteria that have taken it up will not since they inhabit the antibiotic resistant alleles from the plasmids.
6. Bacterial cells that have taken up the plasmids will be selected and transformed, replicating

or

Electroporation:
1.Electrical current is passed through solution containing plasmid and bacteria,Electrical current causes the plasma membrane to become more permeable allowing plasmid vectors to cross through the plasma membrane

97
Q

what is the Insulin production process

A

1.Plasmid vector with ampR and tetR gene for resistance is produced.

  1. Insulin A and B subunit genes are cut using restiction endonucleases (EcoRi and Bamhi) too form sticky ends and recombinant plasmids.DNA ligase is added too reform, the sugar phosphate backbone of the DNA creating transformed bacteria.
  2. Plasmids are added to solution of E.coli bacteria and then either heat shock or electroporation is used to increase the uptake of the plasmids in the bacteria.

4.To identify which bacterial colonies took up bacteria it is added to agar plate with ampR those that survived may have been bacteria.Second test with tetR is used, those that die have the recombinant plasmid since the insertion of insulin subunit gene disrupts the tetR resistance gene.These plasmids are then collected.

5.Plasmids are cut using Ecori again to insert lacz (report gene) into plasmid.LacZ produces b-galactodase.Plasmids containing lacZ are then added too Ecoli bacteria to create transformed bacteria.

6.Lac-z produces B-galactodase which can create a blue coloured compound cause of x-gal.This means colonies that were blue could be identified to have taken up recombinant plasmid.These bacteria are able to produce insulin subunit gene which is attached to B-galactodase.

7.Transformed bacteria that contains the recombinant plasmid are then placed into conditions to reproduce before their membranes are broken down and the human insulin that has been produced is isolated and purified.The two insulin chain have their b-Galactosidase tails removed and are mixed together, which allows the connecting disulphite bonds to form and create functional human insulin.

98
Q

What is a GMO (Genetically modified organism)

A

organisms whose genes have been altered using genetic engirneering technology

99
Q

What are transgenic organisms?

A

includes GMOs in which the alteration to the genome require genetic material from a different species

100
Q

What is a cisgenic organism?

A

Genetically modified organisms that has genes from the same species inserted into its genome. This process is known as cisgenesis, which involves transferring genes between organisms that could otherwise be bred together.

101
Q

How are transgenic plants produced?

A

Gene identification:
- Gene of interest must be identified and isolated

Gene delivery:
-Isolated gene of interest is delivered into the cells via the host organism. This delivery may occur either via,direct insertion of DNA into the genome of the plannt itself, or through the use of bactieral plasmid that is able to transfer DNA between itself and the plant

Gene expression:
-transformed cell is grown repeatedly, using plant tissue cultures under sterile conditions before being applied in the feild for agricultural use

GM host organism is now able to express the new transgene as usesful protein and can regenerate itself

102
Q

Biologicial issues with Genetic engineering

A

Pros
-GM crops produce better than Non-GM crops.this allows more crop to grow on less land and therefore reduce habitat loss due to land clearing
-Insect-resistant GM plants require fewer pesticides, which is good for the environment
-GM foods can have the ability to have improved nutritional content

Cons
-Gm may loose their effectiveness if weeds and pests are able to adapt and gain resistance
-Widespread use of GM crops could result in the loss of genetic diversity within crop populations
-cross-polination between GM crops and wilde species or weeds may cause genes to spread and lead to unforseen consequences.

103
Q

Social issues with Genetic engineering

A

Pros
-more food can be produced, crops are able to grow in more adverse conditions,creates larger profits for farmers
-Improved nutritional content

Cons
-May be costly for farmers
-Complex legal issues surronding the use of GM products may cause farmers stress and anxiety
-Strict packaging and marketing regulations for GMO producers that may not be complied with if the producer and concumer are not educted on these regulations

104
Q

Draw a nucleic acid

A

….look at images in book

Biology sac 1 (9 decks)

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