inquiry question 2 module 6 Flashcards
How do genetic techniques affect Earth’s biodiversity?
definition of biotechnology
use of biological processes, living systems, organisms or parts of organism to benefit humankind
- Driven by human needs to treat disease, maintain food production and preserve the environment
past uses of biotechnology
agriculture = selective breeding
fermentation
medical (ancient antibiotics)
agricultural biotechnology past
selective breeding = practice of choosing particular desirable characteristics, and breeding individuals that possess these traits together in order to produce offspring that exhibit the most favourable characteristics
eg. domestication of cows for greater yield of milk, strength
ethical: animal welfare
benefits: offspring with desirable characteristics
impacts on biodiversity: potentially affect the evolution and long term survival of species as although selective breeding focuses on increasing the occurrence of particular traits → level of genetic diversity in a population can be reduced
fermentation biotechnology past
Microorganisms use the process to convert sugars into energy during anaerobic respiration
Glucose → ethanol + carbon dioxide
bread = carbon dioxide causes it to rise, starch breaks down in sugar –> releases co2
eg. bread, cheese
cheese:
enzyme renin added –> ferments mill –> turns lactose to lactic acid –> curdles milk
medical past biotechnology
Mould fungus produce chemicals that kill or inhibit bacteria
from ancient egyptians, honey and mould to treat infections
present/modern biotechnology
medical = genetic screening, stem cell treatments, gene therapy
manipulate dna = dna splicing, dna amplification, recombinant dna
analyse and visualise dna = agarose gel electrophoresis, gene probes, dna sequencing
genetic screening, medical present biotechnology
Looks for mutations that are known to increase risk of genetic disease eg. cystic fibrosis conducted on adults, newborns and embryos
- Detects genetic diseases early in life to improve patient outcomes
- Identifies whether couples are carrying disease causing alleles before they are trying to conceive
disadvantages:
- Some diseases don’t have 100% penetrance → people can worry their whole life
- Can be used for superficial characteristics
stem cell treatments medical modern biotechnology
stem cells used to replace any type of damaged or non-functional tissue
- transplant to bone marrow, heart disease, parkinsons disease
disadvantages
- controversial
- misleading advertisements that are not based on science
stem cells
undifferentiated cells that can potentially become any type of cell in the body
gene therapy , modern day biotechnology
Experimental technique used to treat hereditary diseases at the molecular level by inserting a gene to replace the missing or defective gene that causes the disease
- crispr - cas9
- Adds a normal copy of the gene to some patients cells → the normal human gene is introduced into a virus → ‘infects’ th epatient;s cell → inserts the normal gene back in the process
- turns genes on and off
- sick cell anaemia = inserting good copy of gene into bon emarror cels to produce normal red blood cells
eg. haemophilia, cystic fibrosis, AIDS, cancer
CRISPR-Cas9
form of gene therapy
- More efficient way of inserting or turning off genes
- uses CRISPR sequence and Cas9 enzyme
gRNA sequence is created to recignise the specific sequence of DNA to e edited within the target sequence, it is attached to the cas9 cutting enzyme and inserted into the target cells, locates sequence and cuts the dna, scientist then edit the exisiting genome by insert, modify or delete a new sequence
CRISPR sequence →Includes fragments of virus DNA that have been left in the genome from a previous viral infection
- grna = recognises the sequence of DNA to be edited and tells the Cas9 where to cut
Cas9 enzyme
- Runs along the DNA of the target cell unwinding the double stranded DNA (dsDNA) searching for the complimentary target sequence and cuts the DNA
process:
- PAM sequence found new newly inserted viral DNA
- CAS9 enzyme uses RNA copies of the spacer sequences as a template to find similar sequences from viruses in the genome and cut them
- When DNA is repaired → most likely contains mutations that turn off the virus gene → prevents it from being transcribed and translated
modern technology to manipulate DNA
dna splicing
- required gene or sequence of bases in a DNA molecule is spliced out, using restriction enzymes that cut DNA at specific base sequences
dna amplification
- DNA polymerase is used to replicate DNA fragments many times before inserted into the new genome
Recombinant DNA
- DNA ligase enzyme used to join pieces of DNA together
modern technology to analyse and visualise DNA
agarose gel electrophoresis
- identify ‘dna fingerprint’ of individual
- dna is fragmented and passed through a gel, distribution fragments can be seen as bands on gel and represent DNA fragment of different size
DNA sequencing
- Used to determine the extract nucleotide sequence of DNA ora gene
antibodies
Small proteins produced by the immune system that can recognise and bind to antigens
- bind to antigens that have invaded the body
- flags antigens as foreign response
antigens
Foreign protein or carbonate complex that triggers/elicit an immune response from the body
