The Search for Better Health Flashcards
What are prions?
A defective form of a protein molecule.
- don’t contain DNA or RNA
- mostly attack nerve & brain cell & go on to alter other proteins
Disease caused?
*Prion diseases can be both infectious & hereditary
BSE Bovine spongiform encephalopathy in cows
CJD Creutzfeld-Jacob Disease in humans
What is a virus?
DNA or RNA wrapped in a coat of protein
- To replicate they invade cells & insert their genetic code into the host cell’s genetic code.
- as they are not technically living, they are only able to reproduce in a living cell
- extremely small & cannot be observed under a light microscope –>difficult to observe & understand
Diseases: HIV, influenza, small pox
What is bacteria?
Single living Procaryotic cell with no internal membrane
-cause disease by:
secreting toxins, invading cells & forming bacterial colonies that disrupt normal cell function.
Diseases: salmonella, bacterial leaf spot
What is a protozoan?
single celled organisms with ann internal membrane
–>DNA in nucleus (eucaryotic)
disease: malaria, giardia
What are fungi?
Eucaryotic, non-photosynthetic cell.
Can be single or multicellular.
Diseases: tinea, thrush
What are macro-parasites?
parasites visible to the naked human eye.
such as: arthropods (ticks), tapeworms,
order of pathogens in order of smallest to largest:
prions viruses bacteria protozoans fungi macro-parasites
identify the role of antibiotics in the
management of infectious disease:
antibiotics are important in treating bacterial-caused diseases by inhibiting cell wall formation, damaging the cell membrane or interfering with the nucleic acid metabolism and cell division.
Examples of antibiotics include penicillin and streptomycin.
What are antibiotics?
antibiotics are chemicals that prevent the growth or development of bacteria.
they have contributed to controlling and eliminiating diseases such as:
leprosy, pneumonia, cholera.
They have improved the life span and quality of life for humans
what are the problems relating
to antibiotic resistance?
The effect of antibiotics has decreased over time due to antibiotic resistance.
Due to the overprescription and misuse of antibiotics:
-strains of resistant, more virulent bacteria have evolved, resulting in super bugs
‘super bugs’ are resistant to most antibiotics. eg. golden staph
Due to these antibiotic resistant strains of bacteria, there is a major risk of future epidemics of disease that we cannot control.
What are the precautions taken to minimise antibiotic resistance?
-individuals must complete their full course of antibiotics, this ensure all bacteria is destroyed
(not finishing course can lead to the selection of resistant bacteria)
-Antibiotics don’t work on viruses, and therefore it is important to ensure the correct prescription of antibiotics to bacteria only diseases
How does a named disease results
from an imbalance of microflora in
humans?
-microbes live in & on the body in a symbiotic relationship.
Candidiasis (thrush)is caused by an imabalnace of microflora.
Thrush is caused by the fungus Candida albicans, which is a natural microorganism in the body. It is usually kept in balance by competition with other microorganisms.
An increase in Candida albicans cells causing Candidiasis (thrush) can be due to antibiotics, steroids, oral contraceptives, malnutrition.
This results in itchy, tender white infected patches in the mouth, respiratory tract and female genital tract.
*antibiotics kill lots of types of bacteria, thus can kill the good bacteria which creates a balance of microflora.
What are the main steps of the treatment of water?
The process goes
- -Sedimentation (removal of large particles through a fine screen.)
- -Activated carbon (adsorbs contaminants-dissolved toxins, colours, tastes/odours that can be then filtered out.)
- -Coagulation (ferric chloride/aluminium sulfate)
- -Flocculation (all flocs gather in large group)
- -Filtration ( Sand and crushed coal, trapping the floc)
- -Chlorination (chlorine added to water to kill bacteria)
- -UV (water to disinfect)
- -Fluoridation (prevent tooth decay)
- -Stabilization
- -Testing for presence of micro disease causing orgs
How to remember: Sedimentation Activated carbon Coagulation Flocculation Filtration Chlorination UV Fluoridation Stabilization Testing for treatment of water
Should Activated Clinton Fall For Charismatic Flying United Seagulls Talking
What are two disease causing orgs?
Cryptosporidium, giardia
What is the role of quarantine in preventing the spread of disease?
aim:
1. to prevent entry of harmful diseases within australia
2. stop the spread of diseases
Why is quarantine important?
- as introduction of foreign pests and diseases = serious environmental and economic impact
eg. protecting native species - quarantine regulations have prevented entry of foot and mouth diseases which can be devastating to livestock industry
- quarantine works well for diseases that have a relatively short incubation period, however are less effective in preventing diseases such with a long incubation period or that are highly infectious
how have public health programs controlled/prevented disease?
Public health program was the grim reaper campaign used to warn of the risks involved in contracting HIV
What is epdiemiology?
the study of the distribution and frequency of diseases
- it is based on the collection, analysis and interpretation of data
- cause and effect!
What are the features of an epidemiology study?
- large focus group
- populations with the occurrence of the disease & with unequal exposure
- allow for analysis factors that may contribute to the occurence of the disease eg, AIDS, gender, ethnicity, occupation
How are epid. studies effective?
epidemiological studies are an effective way of idenitfying non-infetious diseases, and the relationship between the cause and effect
how has the relationship between smoking and lung cancer has been established through epidemiology?
-show a correlation between the no. cigarettes smoked per day, the starting age of the smoker ad the risk of getting lung cancer
What are the 3 trypes of non-infectious diseases?
inherited
nutritional deficiencies
environmental diseases
What are the causes of inherited disease?
-caused by genetic factors as a result of mutations during meiosis
What is an example of an inherited disease?
Down syndrome, hemophilia
What are the causes of nutritional deficiencies?
-deficiency of a protein or vitamin
What is an example of a disease from nutritional deficiency?
scurvy (vitamin C)
Kwashiorkor (protein deficiency)
What are the causes of environmental diseases?
-lifestyle related disease associated with factors in the environment (eg. high stress level, noise, pollution
What is an example of an environmental disease?
-lung cancer from smoking
Why is cause and effect ficcicult to determine?
as there may be many other reasons for the cause of the disease
it is easier to establish a correlation
identify the cause and effect relationship of smoking and lung cancer
- in the 1970s: data was collected from over 1 million american men 7 their smoking habits and a clear correlation was found between smoking & the incidences of lung cancer
- the data was compared against other factors & it was concluded that smoking was the biggest factor in determining the risk of lung cancer.
what are the quarantine measures in Australia?
AQIS monitors movement of goods & services in & out of the country
-restriction of goods:some are forbidden, & others are monitored by AQIS (plants & animal products)
The effectiveness of Australia’s quarantine program?
extremely successful:
-remained free of diseases such as yellow fever & mad cow disease
-
What are the changing methods of dealing with plant and animal diseases?
shift to treatment & control to management and prevention of disease.
- prior to 20th C, limited understanding of disease & diseases were treated ONCE individual was infected.
- shift started in agriculture
What are the changing methods of dealing with plant and animal diseases?
shift to treatment & control to management and prevention of disease.
- prior to 20th C, limited understanding of disease & diseases were treated ONCE individual was infected.
- shift started in agriculture, with genetically resistant crops being grown, so plants didn’t have to be sprayed with as many pesticides
- world wide immunisation programs to eradicate disease
What are the techniques used to prevent and control disease?
- quarantine programs to limit the spread of a disease into a region
- selective breeding and genetic engineering of plants & animals to be more disease resistant eg. BT cotton
- pesticides: limit spread of disease
- epidemiological studies:gain a better understanding of the cause of the spread of disease over a period of time
Define health
Health is defined by the WHO as a state of complete physical, mental and social wellbeing and not merely the absence of disease.
Why can there be problems when defining health?
Health is defined as the wellbeing of the org, not just the absence of disease. This state of wellbeing relates to the physical, mental and social states of the person. As these can vary from day to day and from individual to individual, people can have different levels of wellbeing, yet still be healthy. Health can also vary because of the aging process and people have different perceptions of what their quality of life/health should be.
What is are egs that demonstrates the difficulty of defining disease?
- A person who is fit would say they’re healthy as they don’t have disease,
- whilst a person a chronic disease will say they are healthy if their symptoms had not been too bad that day.
- A person with HIV could be considered if they don’t yet have the symptoms of AIDS yet.
Define disease
Any condition that adversely affects the function of any part of a living thing and is recognised by the presence of specific symptoms.
What are most diseases best understood as? The disruption of homeostasis.
Discuss why there can be probs when defining disease
Disease is defined as a condition that adversely affects the function of any part of a living thing and is recognised by the presence of specific symptoms. Disease is a very broad term and can range from an abrasion on the leg to serious organ malfunctions and cancers. There can be confusion with this definition, however, with regard to disease and disability, eg. Some health refer to arthritis as a disability not a disease. Furthermore, pregnancy can seriously affect the functioning of the mother’s body, yet isn’t considered a disease
Discuss how mitosis can influence the health of a person
- Mitosis is process of cell division when nucleus replicates into 2 identical daughter nuclei. Mitosis is v important for growth and repair and the maintenance of normal cell functioning.
- If process malfunctions, cancer could be caused as this is when cells rapidly divide and don’t specialise or differentiate, making org unhealthy.
- If there’s a malfunction in zygote or early stage embryo, the mitotic error can affect health of whole org.
Discuss how genes can influence a person’s health
A gene is a hereditary unit that controls production of a polypeptide. Polypeptide will control development and behaviour of organisms. If gene malfunctions a metabolic pathway could be disrupted and the ‘health’ of the person would be affected
Discuss how cell differentiation and gene specialisation can influence the health of a person
- Cell differentiation= process that causes a cell to become specialised to perform a specific function. Eg. Skin cell/nerve cell.
- As embryo develops certain genes in a cell become switched on, causing cell to differentiate and become specialised
- Undifferentiated cells can cause tumours
How do you dispose of disposable infected materials through microbial techniques?
autoclaving or disinfection, then incineration
How do you dispose of reusable infected materials through microbial techniques?
autoclaving then washing
autoclaving
means sterilising in a pressure cooker. Items usually left for 15 min in autoclave then allowed to cool
what scientific field did Pasteur create?
microbiology
with regards to beer and wine what did Pasteur demonstrate?
that bacteria caused the souring of beer and wine
to kill bacteria what did Pasteur develop
process of PASTEURisation
Describe the experiment which showed microorganism come from pre-existing microorganisms
swan neck flask experiment
Who developed a vaccine against rabies and used on humans for the first time
Pasteur
Who developed a vaccine against rabies and used on humans for the first time
Pasteur
who conducted experiments that linked a specific bacteria with a specific disease?
Koch
who identified the bacteria responsible for anthrax?
Koch
who demonstrated that specific microorganisms are responsible for causing different diseases and through what process?
Koch, through following his postulates
what method of growing bacteria did Koch develop?
agar plate technique for growing bacterial colonies
• Some agents (for example, viruses and prions), cannot be grown in a lab dish. They grow only if given a living cell.
What is this a limitation of?
Koch’s postulates
Who is often the healthy organism used in Koch’s postulates and how is this a limitation?
Often lab animals (RARELY HUMANS). Because your testing the infectivity of a pathogen on a lab animal, not a human, even if the pathogen doesn’t detectably infect the lab animal, you can’t be certain it won’t infect humans.
Conditions under which an organism is described as a pathogen
- must have enough virulence (enough of pathogen to cause disease)
- enter host or survive on the body without being destroyed by body’s natural acidity and mucus
- escape from one host to another
- survive transmission from one host to another
How do pathogens cause disease symptoms?
- large number of pathogens present are too many for host tissue to function normally
- pathogens actually destroy cells or tissues
- bacteria produces toxins
- Pathogen may not directly harm the host but an excessive immune response by the host may damage tissue
Outline examples of effective quarantine regulations in australia that protect animal health.
Give one example for each
-animals coming into oz are inspected and quarantined
Outline examples of effective quarantine regulations in australia that protect plant health.
Give one example for each
- plant health is protected in oz by quarantine measures such as the ban on transport of fruit interstate to prevent the spread of disease
- all fruit is confiscated at airports and border inspection stations are used to check cargo
explain why quarantine measures for animals coming into oz are effective
- screening and inspection of live animals at border entry has been very effective in keeping the australian live stock industry free from many diseases
- including mad cow disease and foot and mouth disease
- effective in preventing entry of diseased animals, with foot and mouth disease being devastating to the livestock industry.
MacFarlane Burnet Contributions
MacFarlane Burnet developed ‘the clonal selection theory’ , that explains how an organism’s body is able to distinguish between its own cells and those of other organisms.
-he studied viruses, specifically influenza A and his work led to the development of a vaccine which saved many lives and significantly reduced the occurrence of influenza A
What did McFarlane Burnet suggest in his contributions?
He suggested that:
- Individual lymphocytes have the genetic capacity to make one or possibly a few particular antibodies
- The lymphocytes have receptor molecules on their surface. These receptors have the same specificity for antigens as the antibody that the lymphocyte cell can make
- Therefore, when an antigen enters the body, those lymphocytes with receptors that can react with the antigen will be stimulated to differentiate and will produce plasma cells producing antibodies with specificity towards the antigen.
- Individual lymphocytes have the
- Individual lymphocytes have the genetic capacity to make one or possibly a few particular antibodies
- The lymphocytes have what on their surface.
The lymphocytes have receptor molecules on their surface. These receptors have the same specificity for antigens as the antibody that the lymphocyte cell can make
- The lymphocytes have receptor molecules on their surface. These receptors have the same specificity for what?
antigens as the antibody that the lymphocyte cell can make
- Therefore, when an antigen enters the body, those lymphocytes with receptors that can react with the antigen will be stimulated to ______
to differentiate and will produce plasma cells producing antibodies with specificity towards the antigen.
name and outline the roles of 2 types of T lymphocytes in organ rejection
T cells have surface receptors that recognise specific antigens. they activate the helper T cells to produce clones of cytotoxic T cells and memory T cells specific to that antigen and these destroy it by secreting cytokinins.
flocculants in water
alluminium sulfate
ferric chloride
difference between control and prevention
control is when diseases is already present and is about stopping the spread of the disease and controlling its effects. C is for control and community (draining of swamps, anti-malarial vaccines)
Prevention is about preventing the disease from actually occurring.
difference between control and prevention
control is when diseases is already present and is about stopping the spread of the disease and controlling its effects. C is for control and community (draining of swamps, anti-malarial vaccines)
Prevention is about preventing the disease from actually occurring.
P is for protection and person (mosquito nets and repellent).
Disease Control refers to
reducing the number of new infections, the number of people currently infected, and the number of people who become sick or die from a disease in local settings. This is achieved through deliberate efforts such as vaccines, medications, contact isolation, or other public health interventions.
malaria disease can be controlled in local settings…
You can’t get rid of malaria entirely because the mosquito-borne parasites that transmit the disease can develop drug resistance. But you can control it through health care and prevention strategies such as bed nets and anti-malaria medications.
malaria disease can be controlled in local settings…
You can’t get rid of malaria entirely because the mosquito-borne parasites that transmit the disease can develop drug resistance. But you can control it through health care and prevention strategies such as bed nets and anti-malaria medications.
which pathogen has a cell wall?
fungi they are a non-photosynthetic cell eurcaryotic cell. the other smaller pathogens don’t have one!!
Control method for malaria?
spraying breeding grounds with pesticides, reducing number of vectors thereby decreasing likelihood of dissease spread.
