Health, Disease, Defence Mechanisms And Treatments Flashcards
Heath
Being free from communicable and non communicable disease
Cost to the NHS
☀️spend billions of pounds each year on treating and looking after people who are ill
☀️doctors and nurses and other staff salaries
☀️upkeep of hospitals and health centres
☀️drugs and medicines
Pathogens
Microbes that cause disease
HIV which leads to AIDS
💧virus
💧spread by- exchange of body fluids during sex
-infected blood
💧using a condom will reduce risk of infection
Drug addicts don’t share needles
No cure for AIDS
Colds and flu
Virus
💧airborne (droplet infection)
💧flu vaccination for targeted groups
HPV
Human papilloma virus
Virus
💧spread by sexual contact
💧HPV vaccination offered to 12-13 year old girls to protect against developing cervical cancer
Salmonella
💫bacterium
💫from contaminated food
💫cook foods thoroughly. Don’t mix cooked and uncooked food. Treat with antibiotics
Chlamydia
☄️bacterium
☄️sexual contact
☄️using a condom with reduce risk of infection. Treat with antibiotics
Tuberculosis
💧Bacterium
💧airborne (droplet infection)
💧BCG vaccination. Treat with antibiotics
Athletes foot
🌪fungus
🌪spread by contact
🌪avoid direct contact in areas where spores are present eg wear flip flops in changing rooms/swimming pools
Potato blight
🌪fungus
🌪spores spread in the air from plant to plant particularly in humid and warm conditions
🌪crop rotation and spraying plants with a fungicide
Why do you use aseptic technique
Prevent contamination and the growth of unwanted pathogenic microorganism
Why do you heat the inoculating loop?
Why do you cool the loop?
Sterilise it
So not to kill the bacteria that your transferring to petri dish
Why do you flame the neck of the culture bottle
Prevent bacteria escaping
Why is the Petri dish lid held at an angle
Prevent bacteria from air contaminating the dish
Why is the Petri dish sealed with tape
Prevent harmful bacteria escaping
Why is the Petri dish incubated at 25°C
Reduces risk of growing pathogenic microorganism. Don’t grow at 37°C
Why is the Petri dish inverted during incubation
Prevent condensation on lid dropping onto culture
Why is nutrient agar used
Provide food and moisture for bacteria
Body defence mechanisms
How do we stop/prevent infection?
Skin- excellent barrier stops microorganism entering our body
Mucous membrane- lining nose and respiratory tract trap dust and microorganisms and expel them
Clotting if blood- closes wounds prevent blood loss and further entry of microbes
Antigens and antibodies
🌸invading microorganism have protein on their surface that the body recognised as foreign
🌸these proteins are called ANTIGENS and they cause white blood cells called lymphocytes to produce ANTIBODIES
🌸antibodies have a complementary shape to the antigen
🌸antibody patch on to antigens linking together. This clumping, immobilises the bacteria preventing their spread and reducing symptoms in the patient.
🌸It also makes them a larger target for destruction by white blood cells called phagocytes
Phagocytosis
Phagocytes move around the body in blood destroying microorganism directly or destroying those trapped by antibodies.
🌷Engulfs and digests the microorganism
🌷Secretes enzymes which digest the microorganism destroying it
Antibiotics
Eg penicillin
Chemicals produced by fungi that are used against bacterial diseases to kill bacteria or reduce there growth
Primary response
After initial infection, it takes time for the specific antibody to be produced to the antigen. Patient feels unwell before infection is cleared
Secondary immune response
After infection, the body produces memory lymphocytes they remain in the body for many years- these respond quickly and produce antibodies of the body is infected again by the same microorganism
Antibodies response is more rapid and higher level of antibodies produced
Active immunity
Natural
🌸this immunity develops through having the disease
🌸specific antibodies are made to a pathogen
🌸memory cells are made, secondary response much more rapid upon reexposure to same pathogen.
Body makes own antibodies
Lasts for life
Active immunity
Passive
🌸vaccination with a dead or modified form of the pathogen that will not actually cause the disease but still produce an immune response.
🌸antibodies level in blood will rise and the body will make memory lymphocytes
Lasts for life
Passive immunity
Natural
Antibodies are passed from mother across placenta and in the mother milk to child.
Crucial protection against antigens in first few months of life
Foetus can only be given antibodies the mother has encountered
Last few months
Passive immunity
Artificial
Ready made injection of antibodies.
Immediate protection is given and can be life saving.
Short lived
No memory lymphocytes made
Why are booster injections given
The booster injection produces antibodies quicker and in larger volume. The person has now a higher level of antibodies and more memory lymphocytes and is now more immune to the disease.
Antibiotics definition
Eg penicillin are chemicals produced by fungi which are used against bacterial disease to kill bacteria or reduce growth
Overuse of antibiotics leads to
Bacterial resistance resulting in the development of superbugs eg MRS.
Procedures to reduce the incident of superbugs
Procedures to reduce the incident of superbugs and why they are difficult to eradicate
- Not overusing antibiotics when not needed eg viral infection
- Increased levels of hygiene (wearing gloves and immediate cleaning of spillages/ staff and visitors wash hands or use hand gels)
- Isolation of patient that have contracted a ‘superbug’ like MRSA
Vaccinations
Use modified disease-causing organisms to produce raised antibodies level and memory lymphocytes in the blood
Non communicable diseases consequence of
Inherited- some people may carry a gene that predisposes them to some cancers
Lifestyle
Poor diet
Excess sugar and fat
Lead to obesity and type 2 diabetes
Lack of exercise
Energy used in exercise being lower than energy intake is the cause of obesity
Overexposure to the sun
UV radiation causes mutations leading to skin cancer
Misuse of alcohol
Binge drinking can cause liver damage and affect foetal development (foetal alcohol syndrome)
Tobacco smoke
Tar can cause bronchitis, emphysema, lung cancer
Nicotine addictive and affects heart rate
Carbon monoxide combines with red blood cells to reduce oxygen carrying capacity of the blood
Bronchitis
Narrowing of the bronchi and bronchioles
Emphysema
Damage to alveoli reducing the SA for gas exchange
Lung cancer
Abnormal cell devision
Why do smokers have low levels of energy
Carbon monoxide reduces the amount of oxygen carried therefore a lower rate of respiration and energy release
Cause of a heart attack
Blockage caused by a build up of cholesterol deposits leads to clot formation
Restricted blood flow means less oxygen and glucose reaching cells and the resulting reduced cell respiration leads to cell death
Blockage in the Coronary blood vessel restricts blood flow to the heart muscle and causes death of heart muscle cells
How does a stroke happen
Blockage in blood vessel to the brain causes death of brain cells resulting in reduced brain function
Treatments for cardiovascular disease
Angioplasty and stents
- A catheter is inserted into the patients coronary artery
- The catheter has a balloon at its end.
- It also contains a tube of thin wire mesh called a stent
- When the ballon is inflated, it squashes the plaque stretching the narrowed artery
- As the ballon is inflated the stent expands which holds the artery open
- Finally, catheter is removed, leaving the stent in place
Lifestyles factors increase or reduce risk of heart disease and strokes
Excess dietary fats
Smoking
Stress
Lack of exercise
Treatments for cardiovascular disease
Statins and aspirin
Stains are drugs help lower cholesterol in the blood and therefore the rate at which blood vessels can become clogged up with fatty deposits. Statins need to be taken long tong. Cholesterol levels will rise again if person stops
Aspirin helps thin the blood and makes it less sticky reducing the risk of a clot forming
Cancer definition
Uncontrollable cell devision which produces cancer cells, which can result in two types of tumour.
Benign tumour
Encapsulated and not spreading
Malignant tumour
Capable of spreading
Names of both types of tumour
Benign
Malignant
Lifestyle choices can affect the risk of developing certain types of cancer
Cervical - HPV vaccination
Lung- smoking
Skin- UV radiation
Communicable diseases
Can be passed from one person (organism) to another. Described as infectious disease
Non communicable disease
Not passed from one person to another
Aseptic technique
Set Bunsen on blue flame
Pass inoculating loop through flame until red hot
Allow metal to cool
Remove lid and place loop into bacterial culture to coat it
Flame the neck of the bottle by passing it through the Bunsen
Gently spread microbes over surface of agar plate using loop. Hold Petri dish at an angle to prevent contamination with air
Heat metal loop again until red hot
Tape Petri dish in 4 places and then incubate upside down in an oven at 25°C
Clean work surface and hands and safely dispose of bacterial culture by autoclaving
Why incubate Petri dish at 25°
Avoids growth of pathogens
How do you dispose of bacterial cultures
Autoclaving
