an organism must:Takuto said:Q: What are the features of an organism that defines it as a pathogen? (3 marks)
As has already been stated, the Threshold is the minimum stimuli required to produce an action potential. This process is usually refered to a an "all or none" respone as the threshold is either reached or isn't. Depolarisation of the neurons membrane causes this action potential. Migration of sodium (Na+) ions occurs when the threshold is reached and the neurons membrane becomes peremable. This creates a pulse which travels down the axon and is transmitted to the next neuron over the synaps.danz90 said:Question: Define the term threshold and explain why not all stimuli generate an action potential.
lol I'll have a shot from the top of my head.aussiechick007 said:Evaluate the contributions made by both Louis Pasteur and Robert Koch to our present understanding of the causes and possible prevention of infectious diseases (8 marks)
hope im going in the right direction with this answer.WantToDoBetter said:Communication Q: Explain, using specific examples, the importance of correct interpetation of signals by the brain for the coordination of animal behaviour.
danz90 said:lol I'll have a shot from the top of my head.
Louis Pasteur carried out an experiment, in which he disproved the spontaneous generation theory. He placed a beef broth in two swan neck flasks, boiled the beef broth thoroughly to kill any microorganisms. Pasteur then broke the swan neck on ONE of the flasks, so that the mixture was exposed to air. After several days, Pasteur observed that the mixture exposed to air exhibited growing bacterial/fungal colonies, and spoilage of the beef broth. The mixture not exposed to air was still fresh and observed no spoilage at all. Hence, this disproved the spontaneous generation theory, bringing to light the germ theory of disease - that in order for disease to occur, a pathogen must be present from a source. (a pathogen cannot generate spontaneously). Pasteur's conclusions have suggested that the cause of diseaes are pathogens present in air, water and other mediums. This has had an immense impact in our understanding that pathogenic microorganisms are the cause of infectious disease, and has allowed for the base of research into the prevention of such infectious disease.
Robert Koch had conducted experiments to further specificy the causative agents of disease. He developed four principles known as Koch's postulates, used to specify the causative pathogen of a particular disease:
1. The symptoms and pathogen must be present in all hosts infected with the disease.
2. The microorganism must be able to be isolated from the initial host and cultured in a lab.
3. When the cultured microorganism is injected into another host (same speces), the same symptoms should be exhibited, as the initial host.
4. When the same pathogen from the second infected host is cultured and innoculated into a third host, the symptoms should also be those as the initial host.
Koch's understanding of the causative agents of disease, is still incorporated today as a method of determining the causative pathogen of a particular disease, and hence has had a significant impact in contributing to of the causes and possible methods of prevention of disease.
The collaboration of the theories and ideas developed by Pasteur and Koch, have led to the development of measures to inhibit the spread and growth of microorganisms that cause disease (ie pathogens) in an infected host, defined by the particular symptoms if a disease. This includes the development of vaccines, and medications such as antibiotics. Pasteurisation is a widely used process in the food industry based on Pasteur's experiments, to ensure pathogen and disease-free, and thus safe foods be sold to consumers to prevent and control the spread of disease.
It is evident that the contributions of Pasteur and Koch, have had an immense and significant impact upon our understanding of the causes and possible prevention and control of disease in our society.
Imqt, i love your sig BPharm 2009 FTW!
the significance of dna replication is tht exact copis of genes are made. this is only possible because dna is a double helix, and bases pair up commplementary such as g-c and t-a. the process include:hoochiscrazy said:Describe the process of DNA replication and explain its significance.
midifile said:They might have something like a long paragraph on cervical cancer and then say "using this or another example explain the role of vaccinations in controlling or preventing disease"
They often do things like that
We don't need to know anything, if they talked about equine our knowledge of Quarantine etc. would be applied.imqt said:oh ok, was wondering cause we havent touched anything to do with cervical cancer...i guess we bring inn our general knowledge here...we can use other examples such as small pox, polio and diphtheria; ones which are directly related to syllabus?
how about equine influenza? what do people know about this
well u would tie in your knowledge of vaccinations and how they work in preventing and controlling spread of disease.imqt said:oh ok, was wondering cause we havent touched anything to do with cervical cancer...i guess we bring inn our general knowledge here...we can use other examples such as small pox, polio and diphtheria; ones which are directly related to syllabus?
how about equine influenza? what do people know about this
k kool thanks =)dolbinau said:We don't need to know anything, if they talked about equine our knowledge of Quarantine etc. would be applied.
danz90 said:well u would tie in your knowledge of vaccinations and how they work in preventing and controlling spread of disease.
It is likely that the 8-marker will have some sort of stimulus. And if its about cervical cancer, it will mention that human papilloma virus (HPV) causes cervical cancer. Then you wuld go on to talk about how vaccinations would prevent and control the spread of this virus, hence to prevent cervical cancer.
The equine influenza.. again just apply your knowledge of vaccinations and/or medication that prevents the spread of the equine influenza virus, as well as quarantine measures.
Pretty straightforward IMO.
But my teacher told me, its these 8 marker questions that will distinguish band 6 students from band 5 students.
Experienced teacher judges look at these 8-markers very closely when they look at determining the raw band 6 cut off.