8.7 Problems with the synapses Flashcards
what is the neurotransmitter that is affected in someone with Parkinson’s disease?
Dopamine
Why do people have Parkinson’s disease?
dopamine secreting neurons in the basal ganglia/midbrain die
What are the main symptoms of Parkinson’s disease?
stiffness and tremor of muscles, slowness of movement, poor balance and walking problems
what do MAO inhibitors do?
they stop MAO from breaking down excess dopamine
what do L-dopa drugs do?
they are converted into dopamine in the brain to increase the concentration of dopamine and control symptoms
What are dopamine agonists?
Drugs activate the dopamine receptor directly to trigger action potentials
how can gene therapy help Parkinson’s disease?
Genes for proteins that increased dopamine production and that promote the growth and survival of nerve cells are inserted into the brain
what is deep brain stimulation?
The use of electrodes in the brain in specific affected areas
what causes schizophrenia?
Excess dopamine
how can schizophrenia be treated?
With drugs that block the binding of dopamine to its postsynaptic receptor sites
what is the neurotransmitter that plays a role in depression?
Serotonin
why does serotonin have a big effect on the brain?
Neurons that secretes serotonin extend into the cortex, the cerebellum and the spinal cord
what is depression caused by?
A lack of serotonin, but it is multifactorial
Why are twin studies are beneficial for studying diseases?
They help determine if it has a genetic cause and it can show environmental influences
what drugs were originally used to treat depression?
MAOIs
what is the used to treat depression now and how do they work?
SSRIs
They inhibit the retake of serotonin from synaptic clefts so serotonin levels increase and more action potentials are produced
what effect does MDMA have on neurotransmitters?
It increases the concentration of serotonin
What is the human genome project?
an international scientific research project with the goal of determining the base pairs that make up human DNA and of identifying, mapping and sequencing all of the genes of human genome
what have genomic studies indicated about non-coding DNA?
that some of it is highly conserved suggesting that they somehow confer a selective advantage
how is the identification of candidate genes being beneficial?
They can be screened for mutations and drug targets can be found
What are the main ethical problems with the human genome project?
patents
Records of individual genotypes
medical treatments will initially be very expensive
discrimination in employment and insurance
what is artificial selection?
The selection of alleles for characteristics that are agriculturally valuable
what enzymes are used to remove gene in genetic modification?
Restriction enzymes
what is used to insert genes in genetic modification?
Ligase enzymes
what methods can be used to insert foreign genes into plant cells?
Using bacteria that carry genes into plant DNA
Minute pellets that are covered in DNA inserted using a particle gun
viruses
what is used to remove cells that do not have the new genes?
Marker genes
how do marker genes work?
these are antibiotic resistant genes that when the plant cells are exposed to an antibiotic, allow them to survive
How can genes be inserted in genetically modified animals?
Injecting DNA directly into the nucleus of a fertilised egg or retroviruses
what factors about health are concerning when it comes to genetic modification?
Transfer of antibiotic resistant genes to microbes
Formation of harmful products by new genes
transfer a viruses from animals to humans
what are the environmental issues that arise from genetically modified crops?
Transfer of genes to non-target species
The possible breeding of super weeds
The possibility that GM crops will lead to the increased use of chemicals in agriculture
why might GM crops be bad for developing countries?
they are unlikely to be able to afford expensive licenses to use the new technology and may be outcompeted by those that can
