CB5 - Health, disease and the development of medicines Flashcards
(36 cards)
What is Health?
A state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.
What is the diff between communicable and non-communicable disease?
Communicable are disease that can be spread between individuals.
Non-communicable can’t be transmitted between individuals.
Explain why having one disease makes you vulnerable to get another diaease?
If you are affected by one, your body may become weak and less able to fight off other.
Describe Cholera?
Caused by bacterium
Causes Diarrhoea
Spreads via contaminated water
Prevent by having clean water supplies
Describe Tuberculosis?
Caused by bacterium
Causes lung damage
Spreads via air
Prevent by avoiding crowded space and wear masks
Describe Malaria?
Caused by protist
Causes damage to red blood cell and liver
Spread via animal vectors
Prevent by insect repellent and nets
Describe Stomach ulcers?
Caused by bacterium
Causes stomach pain and vomiting
Spread via eating contaminated water or food
Prevent by drinking clean water and hygienic food
Describe Ebola?
Caused by virus
Causes fever with bleeding
Spread via bodily fluids
Prevent by isolating infected individuals
Describe Lytic pathway?
The virus uses its protein spikes to pierce into the host cell.
Next, the virus injects its DNA into the cell, forming new parts for the virus.
Then, these parts assemble into new viruses. This keeps happening.
Finally when the cell can hold no more, the cell bursts (Cell lysis) releasing the virus particles into the host organism to infect more cells.
Describe Lysogenic pathway?
The virus uses its protein spikes to pierce into the host cell.
Next, the virus will inject its DNA into the host cell. Here, it will combine with the host’s DNA. Now the host cell will divide and replicate, each cell containing the viral genetic material.
Describe Chlamydia?
Caused by bacterium
Causes infertility
Spread by intercourse
Prevent by using protection or screening
Describe HIV?
Caused by virus
Kills white blood cell and eventually leads to aids
Spread by bodily fluids
Prevented by using protection
Describe physical barriers plants uses to prevent from pathogen?
- Leaves and stems have waxy cuticle, provides barrier to stop pathogens entering. Also stops water collecting which can stop pathogens in water
- Surrounded by cell walls made from cellulose.
Describe chemical barriers plants use to prevent from pathogen?
Produce chemicals that help prevent damage to plant.
1. Produce chemicals called antiseptics which kill pathogen
2. Produce chemicals to deter pests.
Some chemicals can be used to treat human disease like Aspirin found in willow trees.
How can plant diseases be detected?
- Observing changes to the plant in a different environment
- Detecting pathogen DNA on a plant
Describe physical barriers humans use to prevent from pathogen?
- Skin acts as barrier and if it gets damaged, blood clots seal it
- Hair and mucus in your nose trap particles that contain pathogen
- Cells in trachea and bronchi produce mucus which trap pathogen. Bronchi have cilia - hair like structure waft mucus to back of throat.
Describe chemical barriers humans use to prevent from pathogen?
- Stomach produces hydrochloric acid and kills pathogens swallowed
- Eyes produce chemical called lysozyme which kills bacteria on surface of eye.
How does immune response attack pathogens?
Every pathogen has antigens on it’s surface.
When B-lymphocyte (White Blood Cell) come across pathogen, it produces antibodies which bind to the pathogen.
Describe memory lymphocytes and role in secondary response?
Whilst antibodies are made to fight against a pathogen, memory lymphocytes are also produced. Their role in a secondary immune response is that if the same pathogen re enters the body, these memory lymphocytes will remember the pathogen and be able to deal with it extremely quickly
What is the body’s response to inactive pathogen?
It is immunisation where inactive pathogens are injected with antigens so B-lymphocyte release antibodies which also create memory. When an active pathogen comes, it is ready to attack.
What are the Advantages and disadvantages of Immunisation?
Advantage:
- If big outbreak of disease, country could do something called Herd immunity where everyone gets immunised and the disease will not be passed on that much.
Disadvantages:
- Does not always work
- May have a bad reaction but very rare
Why can antibiotics only kill bacteria?
They prevent the developing processes in the bacterial cells by attacking their cell walls, as well as not affect the host cells in the process.
Explain the aseptic techniques?
- Use an autoclave (High pressure steam machine) to sterilise the Petri dish.
- Before transferring bacteria using an inoculating loop (wire loop), run it through a hot flame, so that unwanted micro-organisms are killed.
- Cover the completed Petri dish with a lid which is lightly taped on. This ensures no micro-organisms from the air enter the Petri dish.
Practical : Investigate effect of substance on bacterial growth
- Place paper disk soaked in diff types of antibiotics on agar plate that has even covering of bacteria
- Antibiotics should diffuse into agar. Antibiotic-resistant will grow on agar around paper where bacteria has died (Inhibition Zone)
- Make sure use a control (Paper disk not soaked)
- Leave plate for 48 hours at 25 Celsius
- More effective antibiotic, larger inhibition zone