SB5 - Health, Disease And The Development Of Medicines Flashcards
What’s the world health organisation (WHO)
Responsible for making ways to improve health across the world -
According to them good health means more than just feeling well it’s a state of complete physical, social and mental well being
What is physical health?
Includes being free from disease, eating and sleeping well, getting regular activity, limiting intake of harmful substances
What’s social well being
Includes how well you get on with other people and how your surroundings affect you
What’s mental well being
Includes how you feel about yourself
What are some reasons people have poor health
Can’t afford a healthy diet
In LEDCs where there’s more disease and fewer hospitals
What is a disease
A problem with a structure or process in the body that’s not the result of an injury
What could be the cause of a disease
Might be due to microorganisms getting into the body and changing how it works
What are the microorganisms that cause disease also known as
Pathogens
What is a communicable disease
They can be passed from an infected person to other people
What is a non communicable disease
They are not passed from person to person - caused by a problem in the body eg fault in the genes or as a result of way we live - our lifestyle
What does “some diseases can be correlated” mean
So that having one disease means a person is more likely to have another disease
Tell me the cause of a correlation
A disease that damages the immune system can make it easier for other pathogens to cause disease
A disease that damages the body’s natural defences and barriers allowing pathogens to get into the body more easily
A disease can stop an organ system from working effectively making other diseases to occur
What is genetic disorder
A type of non communicable disease caused by faulty alleles of genes - genetic disorders can be passed to offspring but nothing else!
What is malnutrition
It’s a non communicable Disease as a result of s poor diet
Occurs when you get too little / much of particular nutrients from your food
What’s a deficiency disease
The lack of a certain nutrient can cause a specific deficiency disease
What is protein deficiency also known as
Kwashiorkor
What are some kwashiorkor symptoms
Enlarged belly, small muscles, failure to grow properly
What are some good sources of protein in diet
Meat, fish, dairy, eggs, pulses (eg lentils)
What’s a vitamin c deficiency also known as
Scurvy
What are some symptoms of disease
Swelling and bleeding gums, muscle and joint pain, tiredness
What are some Good sources of vitamin c in diet
Citrus fruits, some vegetables eg broccoli
What is vitamin D/ and or calcium also known as
Rickets (vitamin d) osteomalacia (calcium)
What are some symptoms for vitamin d/ and or calcium
Soft bones, curved leg bones
What are some good sources of vitamin D and calcium
Oily fish (vitamin d)
Dairy products (calcium)
What is iron deficiency also known as
Anaemia
What are some symptoms of anaemia
Red blood cells that are smaller than normal and reduced in number, tiredness
What are some good sources of iron
Red meat , dark green leafy vegetables, egg yolk
What is a drug
A chemical that changes how the body works
What drug is found in alcoholic drinks
Ethanol
What happens to ethanol in the body
Broken down in liver
What’s can large amounts of Ethanol lead to
Lead to liver disease - including cirrhosis
What is a cirrhotic liver like
Paler, rougher and much harder - it does not function well and can result in death
What is obesity and his is it formed
Malnutrition caused by a diet that is high on sugars and fat - where large amounts of fat formed under skin and around organs such as the heart and kidneys
Too much fat can increase diseases such as cardiovascular disease
What do we still need some fat
To cushion our organs when we move, to store some vitamins and provide a store of energy
How is cardiovascular disease caused
As a result of circulatory system functioning poorly - one sign is high blood pressure which can lead to heart pain or even a heart attack
What is body mass index (BMI)
Measuring the amount of fat on the body - it assumes the mass of other body tissues are in proportion to height
What number of BMI is considered
Obese
30
How is bmi calculated
mass divided by height ^2
What fat is linked closely with cardiovascular disease linked with
Abdominal fat
What is a better way to measure abdominal fat
Waist measurement divided by hip measurement to get waist:hip ratio
How can tobacco smoke cause damage to lungs
It contains harmful substances when breathed in they can be absorbed from lungs into blood and transported to body that can damage blood vessels, increase blood pressure, make blood vessels narrower and increase the risk of blood clots in blood vessels
^ this can lead to cardiovascular disease
How can you treat high blood pressure
Exercise more, give hm smoking
If very high could be given medicines to reduce it
Who can a narrower blood vessel be widened
By inserting a stent (small mesh tube) at the narrowest last to hold it open
How can blocked arteries be bypassed
By inserting other blood vessels so that the heart tissues is supplied by oxygen and nutrients again
^people who have these treatments may have to take medicines for rest of lives to help prevent a heart attack or stroke
What symptom does cholera cause
Diarrhoea (watery faeces)
What did Filipino Pacini
He www the first person to isolate a bacterium from people with cholera
And to suggest that bacterium caused the disease
What pathogen causes cholera
Vibrio cholerae
- Robert Koch showed this
How did Robert Koch prove that vibrio cholerae causes cholera
The bacterium was always found in the diarrhoea from people with cholera but no in the diarrhoea from people with other diseases
What’s a pathogen
A microorganism that causes disease
What is a host
Eg humans, an organism that is infected by the microorganism
What is Chalara dieback
It’s disease of ash trees caused by fungus
Symptoms include lesions on trunk and branches, leaves dying earlier than usual and dieback of the crown (top of branches)
What are viruses
They are not true organisms because they don’t have a cellular structure
How do viruses multiply
By infecting a cell and taking over a cell DNA copying processes to make new viruses
Different viruses infect different organisms, including bacteria
They can affect many parts of body at once
What is the Ebola virus
It causes the breakdown of blood vessels and liver and kidney cells this leads to internal bleeding (haemorrhaging) and so causes haemorrhagic fever
What is internal bleeding also known as
Haemorrhaging
What’s HIV (human immunodeficiency virus)
It attacks and destroys white blood cells in the immune system
How does AIDS develop
People infected with HIV often develop AIDS (acquired immune deficiency syndrome) because their immune systems cannot protect them from secondary infections
Many people die from these other infections such as TB
Tell me about hidden pathogens
Many types of bacteria live in our bodies - some essential for our health
Others may not affect us most of the time
What’s HELIOBACTER PYLORI
50 per cent of people have that bacteria in the stomach and over 80 percent of these people never show symptoms of disease by these bacteria
Others may develop sore areas called ulcers where the bacteria attack the stomach lining
How can we find how to stop the spread of disease
If we know how they spread, then we can find ways of stopping that disease
How can colds, flu and tb spread
When sneezing or coughing, it sends droplets containing pathogens into the air
Most flu viruses can survive for about a day
How does fungi spread
Can spread in air and as tiny though spores in plants
Eg strong winds can carry Chalara dieback spores over long distances
Tell me some examples of a pathogen that spreads in water
Such as bacteria that can cause cholera, typhoid or dysentery
What’s good hygiene
Keeping things clean to remove or kill pathogens
Outbreak of disease such as cholera occur when hygiene is difficult, such as in poor areas after environmental disasters or in refugee camps
What is the oral route
Where pathogens enter through the mouth
HELIOBACTER bacteria are thought to spread…
When people touch other people’s food after touching they mouths or going to the toilet (oral-faecal transmission)
Or on the feet of flies that have fed on infected faeces and then landed on food
What’s an epidemic
It’s when many people become infected when burying those who has died from Ebola
How is malaria spread
It’s a protist that is carrier in blood by mosquitos that sucked blood from an infected person
The mosquito injects the protist directly into the blood of the next person it feeds on
What is a vector
Organisms that carry pathogens from one person to the next
Controlling the spread of the pathogen may involve controlling the spread of the vector
What is a capsid
FOUND IN VIRUSES One or more strands of genetic material surrounded by a protein coat
Many viruses have additional layers on the capsid
What kind of cells do viruses do invade processes of to replicate
Plant cells
Bacterium cells
Human eg HIV and Ebola virus
How do viruses copy the genetic material
By taking over cell processes so cell copies viral genetic material and make new viral genetic material and proteins, these components assemble in to new viruses
How do viruses escape the cell?
Some cause the complete breakdown of cell or LYSIS
Others leave by pushing out through cell membrane
^ both methods damage cell and causes disease
What happens to viruses once they have left the cell
They can go and infect other cells
Tell me about the lysogenic pathway
their genetic material inserts into the cells genetic material so each time the cell divides the viral genetic material is too - this can ballet many times
At some point the virus’s genetic material triggers the copying of itself and making viral proteins and switches to the lytic pathway
Tell me about the lytic pathway
When a virus causes the cell to go through lysis and immediately starts making copies of the virus
Tell me the steps of the lytic pathway
Virus attaches to cell and injects genetic material
Viral genetic material forms a circle
New viral genetic material and proteins are produced and assembled
Cell lyses and releases virus’s
Tell me the steps in the lysogenic cycle
Viral genetic material inserts itself into the bacterial chromosome
Bacterium/cell reproduced normally, replicating viral Genetic material with it
The cell/ bacterium reproduce many times
The viral genetic material separates from the bacterial chromosome triggering the lytic cycle
How can the effect of viruses on bacteria be studied
Using bacterial lawn plates made with nutrient agar and on top the tin layer of bacteria grows
Then the virus is added to plate and after a day or two, clear circles can be seen where bacteria have been killed by ghetto virus
How is the cross sectional area of the clear circle calculated
pi X r^2
What does the size of the clear circles mean
The larger the area, the more effective the virus has been at replicating and killing bacteria
What Is the cuticle
A waxy layer on the leaf that acts as a physical barrier so it is difficult for pathogens to get to cells beneath
What is bark
A physical barrier on trees that protects the stem
How do some pathogens get through the physical barriers on plants
They can release enzymes that soften cell walls
Others infect parts of the Plant thag have weaker walls eg young shoots and parts not growing well
Tell me about chemical barriers of plants
They can use chemical substances to deter herbivores and pathogens only when attacked
Tell me what chemical defences one type of wild potato uses
Releases a substance into the air when attacked by aphids which is the alarm substance that aphids release when attacked by a predator so other aphids fly away
How do fox gloves use Chemical barriers
They produce poisons all the time by this takes energy so it must be worth the cost to the plant to make them
What is aspirin
It’s produced from salicylic acid which can be produced from meadowsweet and willow trees
It can be used to control symptoms of pain or fever
What is artemisinin -
it kills the plasmodium protists that cause malaria
It’s extracted from the wormwood plant
What are aseptic technique
Tests to not contaminate equipment from microorganisms
Eg autoclave to sterilise equipment and growth medium
How can drones be used by farmers
They can see if crop plants are under stress
When do crop plants show signs of stress
When conditions are not good for growth eg too much or little water, when soil lacks nutrients or when plants are attacked by pests or diseases
Why is identifying the cause of stress essential
So the farmer can treat the stress and crop correctly to prevent the loss of yield
What is the yield
The amount of useful product
What is the first step to identifying the cause of stress
Begins with careful observations - looking for visible symptoms
Photos can be checked against photos or other informations to suggest a cause
What are some visible symptoms of plant stress
Changes in growth
Changes in colour
Blotching of leaves (lesions - areas of damage ) on stems or leaves
What’s a distribution analysis
It looks at where the damaged plants occur
Flooding, drought, or lack of a soil nutrient will create similar symptoms in all plants in the area
Diseases that spread will adept plants over a wide area but most obviously where the wind first reaches the crop
Tell me about soil pathogens
Usually only found in small areas
So create an obvious pattern of damaged plants
How can tests be used to get an identification of a crop disease
The tests should allow a diagnosis of the of the problem
What tests can be done to diagnose a plant disease
This is diagnostic testing
Growing a pathogen from damaged crop plants o
Using technology to identify presence of genetic material of a pathogen
When farmers send damaged plants for testing, they will also send in a report about other observations they have made, may also send soil samples to be tested for nutrients and toxins - helps to be more certain of the cause of a problem
How can the skin be a physical barrier
Skin is very thick and pathogens have difficulty getting past it
How can pathogens pass over skin
They can cross by wounds or by an animal vector that pierces the skin
What features does the skin also have
It has glands that can secrete substances on to the skin surface
What does lysozyme do
It’s an enzyme that breaks down the cell walls of some types of bacteria
It’s a chemical defence as it reacts with substances in the pathogen and this kills the pathogen or makes them inactive
Where is lysozyme secreted
In tears from Eyes
Saliva in the mouth
Mucus
What is mucus and how is it a defence
It protects thinner surfaces of the body
It’s a sticky secretion produced by cells lining the many openings eg mouth, nose, that pathogens could use to enter the body
Dust and pathogens get trapped in the mucus
How are ciliated cells specialised (cilia)
They are specialised to move substances such as mucus across their surfaces
This helps to carry dust and pathogens away - either out of body or into the throat where they enter the digestive system
Tell about hydrochloric acid as a chemical defence
Some cells in the stomach lining secrete hydrochloric acid - reducing the ph of the stomach contents to about 2
At this acidity, many pathogens are destroyed
Tell me an example of a type of bacteria that is adapted to survive in the stomach
HELIOBACTER pylori
What is a sexually transmitted infection (STI)
When a pathogen is transmitted through sexual activity
Eg chlamydia bacterium or HIV virus - spread by contact with sexual fluids (semen or vaginal fluid)
How can the chance of getting a STI be reduced
By using an artificial barrier eg a condom
Tell me how a pregnant women can spread HIV and CHLAMYDIA
The mother can pass it on to an unborn baby which can harm the baby
May also be spread in blood eg sharing needles and injecting drugs
What is screenings
It identifys an STI so people can be treated
Blood given to people who have lost a lot of blood if screened to make sure there are no HIV pathogens or any other particles
What are antigens
All virus and cell Particles have molecules in there outer surfaces that identify if something inside the body is a cell of the body or if it has come inside
What is a lymphocyte
A type of white blood that instead of antigens have antibodies on their sugar
The antibodies attach to the antigens on a pathogen and the lymphocyte is activated
What happens when a lymphocyte is activated
It will divide rapidly to produce identical lymphocytes with the same antibodies
Some lymphocytes release large amounts of antibodies into blood so they attach tk pathogens to kill them or cause another part of the immune system to destroy them
What are memory lymphocytes
When some lymphocytes with antibodies to match the pathogen after a pathogen has Been killed remains in blood
So if the same pathogen tries again the memory lymphocytes cause a much faster secondary response and means your immune
What’s a vaccine
It contains weakened or inactive pathogens or bits of the pathogen that include the antigen
Vaccine can be objected or taken by mouth to allow memory lymphocytes to be created and so immunity
What is herd immunity
The chance of coming into contact with an infected person (it’s usually very low with vaccines)
How was penicillin discovered
In 1928, Alexander Fleming noticed something strange on an agar plate covering in bacteria that he had left for several weeks
Where mould had grown, the bacteria had been killed
He had discovered that the mould made penicillin
What is an antibiotic
They are substances that either kill bacteria or inhibit their cell processes, which stops them growing or reproducing
They don’t have this effect on human cells
Makes them useful for killing bacterial infections that the immune system cannot control
What is antibiotic resistance
Many kinds of antibiotic have developed to work in different ways which is important Becuase all types of bacteria have different structures and they do not all respond in the same way to a particular antibiotic
Many kind of bacteria are evolving resistance so they are no longer harmed by the antibiotic
What is the first test of developing a new medicine
Pre-clinical when it’s tested on cells or tissues in a lab
It shows if the medicine can get into the cells and have the required effect
Checks for side effects - causing unintended changes that may be harmful
Testing tries to make sure the harmful side effects are limited
What’s the second stage of testing a medicine
Testing may then be tested on animals to see how it works on a whole body without risking humans
What’s the third stage to testing a medicine
A small clinical trial on a small number of healthy people to check it’s safe and the side effects are small
What’s the last stage to testing a new antibiotic
A large clinical trial on many people who have the disease that the medicine will be used to treat
It works out the dose (correct amount to give) and checks for different side effects in different people
Only if a medicine passes all the tests can a doctor prescribe it for treating patients
How do pregnancy tests work
Detect a Hormone only produced in pregnancy so monoclonal antibodies match and stick to any kind of protein eg hormones or enzymes and
What are monoclonal antibodies
They are identical antibodies
When can a lymphocyte not divide anymore
Once it starts to produce the monoclonal antibodies
How do you get around the problem of lymphocytes not being able to divide once making antibodies
You make hybridoma cells
How are hybridoma cells made
Fusing a lymphocyte that produces right kind of antibodies with a cancer cell that divides rapidly
Tell me the stages to making a hybridoma cell
A particular antigen is injected into a mouse, it produces the lymphocytes that make antibodies against the human hormone
A cancer cell is fused with lymphocyte from mouse
The hybridoma cell can both divide and make antibodies against the human hormone - these are monoclonal antibodies
What things can the antibodies stick to
Hormones enzymes,
Specific cells eg cancer cells or platelets
How can monoclonal antibodies be used for medical diagnosis
Often done by making antibodies slightly radioactive so when they attach to cancer cell the radioactivity can be detected using A PET scanner and so cancer position can be found
Many people with cancer are given drugs (chemotherapy) or ionising radiation (radiotherapy) to kill cancer cells
Cancer cells can be found and so the drug can be delivered to the right places just to the cancer cells that need jt to reduce the amount of drugs needed and reduces the risk of damaging healthy cells
