Intro to Y12 2025 Flashcards
Outline the steps (1-6) in bacterial transformation
Isolate gene for insulin chain A
Use reverse transcriptase to get c.DNA from isolated mRNA so that it contains no introns.
Cut gene and plasmid using the same endonuclease.
Stick insulin gene into plasmid using DNA ligase which joins the sugar phosphate backbone.
Transform bacteria using heat or electroporation and check for successful transformation by growing on an antibiotic plate with ampicillin and then an antibiotic plate with tetracycline
Bacteria with no plasmid will not grow on the ampicillin plate, successfully transformed bacteria with the non-recombinant plasmid will grow on both plates and the successfully transformed bacteria with the recombinant plasmid will only grow on the ampicillin plate.
How many polypeptides make up insulin?
2
What is the function of reverse transcriptase?
Convert c.DNA from isolated mRNA so that it contains no introns.
Why is reverse transcriptase used in the process?
So the introns are removed and a functional insulin is produced.
What is used to cut the plasmid when producing insulin?
Endonucleases
What is used to join the plasmid and insulin gene?
DNA ligase
What is the purpose of the AmpR and TetR genes in the plasmid?
To check for successful transformation of the bacteria
What is a recombinant plasmid?
A plasmid with the target gene (insulin gene)
What is the function of the promoter region?
Allows RNA polymerase to attach and transcribe the DNA
Which bacteria will only grow on ampicillin?
Bacteria that are successfully transformed with the recombinant plasmid
Which bacteria will grow on ampicillin and tetracycline?
Bacteria that are successfully transformed with the non-recombinant plasmid
Which bacteria will not grow on ampicillin or tetracycline?
Bacteria that have not been successfully transformed
Which antibiotics will bacteria that have been successfully transformed with the non-recombinant plasmid grow on?
Ampicillin and Tetracycline
Which antibiotics will bacteria that have been successfully transformed with the recombinant plasmid grow on?
Ampicillin only
Which antibiotics will bacteria that have not been successfully transformed with the recombinant plasmid grow on?
None (not ampicillin or tetracycline)
Qualitative data
Qualitative data is descriptions e.g. colour and is represented with a bar graph
Quantitative data
Quantitative data is numerical data e.g. 10 seconds and is represented as a line graph or histogram
Independent Variable
The independent variable is a factor that is changed or manipulated in an experiment to determine its effect on the dependent variable.
Dependent Variable
The dependent variable is measured to determine if the change or manipulation of the independent variable had any effect.
Control Variable
Something that is kept constant throughout the experiment.
Control group
A control group is where the factor affecting change is removed to provide a baseline for a comparison against the experimental group.
Experimental method scaffold
There will be two ….
In the experimental group………… will be changed by ………………….
Add …… to a test tube.
Add…..
Add….
The ……………..will be measured by ……………………after
All other variables will be kept the same e.g. ………………………
Repeat the above for the other ….*not relevant if it is an all or nothing.
For the control group repeat the above but with no ……………….
Repeat the experiment ………….
If ……………. then …………………
Accuracy
The accuracy of a measurement relates to how close it is to the ‘true’ value of the quantity being measured.
Improve accuracy
Accuracy can be improved by using a better measuring tool that is being used to measure the dependent variable or collecting quantitative data instead of qualitative data
Precision
Precision is how closely a set of measurement values agree with each other.
Improve precision
To improve the precision, you can make sure everything else is controlled and repeat your experiment more to spot anomalies and variation within the results.
Reproducibility
The closeness of the agreement between the results of measurements of the same quantity being measured, carried out under changed conditions of measurement. These different conditions include a different method of measurement, different observer, different measuring instrument, different location, different conditions of use, and different time.
Repeatability
The closeness of the agreement between the results of successive measurements of the same quantity being measured, carried out under the same conditions of measurement. These conditions include the same measurement procedure, the same observer, the same measuring instrument used under the same conditions, the same location, and repetition over a short period of time.
Cellular respiration
The release of energy from glucose in cells.
Aerobic cellular respiration
the release of energy from glucose in the presence of oxygen
Aerobic cellular respiration word equation
Glucose + oxygen –> carbon dioxide + water
Aerobic cellular respiration stages and locations
Glycolysis (cytosol)
Krebs cycle (mitochondrial matrix)
Electron transport chain (mitochondrial cristae)
Draw a mitochondria
Describe glycolysis
Glucose is broken down into two pyruvate molecules and two loaded co-enzymes
Inputs to glycolysis
Glucose, 2 NAD+, 2 ADP + Pi
Outputs of glycolysis
Pyruvate, 2 NADH, 2 ATP
Describe the Kreb’s cycle
Removal of H+ ions from pyruvate creating, ATP, loaded co-enzymes and CO2
Inputs Kreb’s Cycle
Pyruvate, 8 NAD+, 2 ADP + Pi
Outputs Kreb’s Cycle
Carbon dioxide, 8 NADH, 2 ATP
Describe electron transport chain
H+ ions are used to create a concentration gradient to drive the synthesis of ATP. Oxygen is the final hydrogen ion and electron acceptor to form water.
Inputs electron transport chain
Oxygen, 10 NADH, 26-28 ADP + Pi
Outputs electron transport chain
Water, 26-28 ATP, 10 NAD+
Co-enzyme
In general, these are molecules that assist enzymes that have loaded or unloaded forms which go between reactions in a cell in a cyclical manner.
Role of NADH
Coenzymes assist enzymes, NAD+ carries hydrogen ions and electrons by forming NADH and moves from glycolysis and Krebs cycle to the electron transport chain in a cyclical manner.
Role of ATP in aerobic cellular respiration
Coenzymes assist enzymes, ADP + Pi carries energy by forming ATP it moves between glycolysis, Krebs cycle and the electron transport chain from parts of the cell in a cyclical manner.
Net ATP output aerobic cellular respiration
30-32 ATP
Evolution
change in allele frequency over time.
Allele
Variation of a gene at a particular gene locus.
Natural selection scaffold
VA – There is variation in the phenotypes in the __ population due to random mutations as ___
ST – All organisms face a daily struggle to survive and reproduce. The ___ struggle because _____ which is the selection pressure
SE – The ____ have a selective advantage as ___
IN – The organisms that have a selective advantage (___), survive, reproduce and their offspring inherit the alleles for the trait of ___
E – Evolution occurs by natural selection and there is a change in allele frequency over time and the ___ population becomes better suited to its environment.