B5 - Health, Disease and the Development of Medicines Flashcards
What is the definition of
health?
and who is this according to?
a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity
according to the World Health Organisation (the WHO)
Define
disease.
a condition where part of an organism doesn’t function properly
What are the
two different types of disease?
and what do these mean?
- Communicable - diseases that can be spread between individuals
- Non-communicable - diseases that can’t be transmitted between individuals
Define
pathogen.
an organism that causes communicable diseases
What are some exmaples of
pathogens?
(4)
- viruses
- bacteria
- fungi
- protists
What are the symptoms/effects of
cholera?
and what pathogen causes this?
diarrhoea
a bacterium called Vibrio cholerae
What are the symptoms/effects of
tuberculosis?
and what pathogen causes this?
coughing and lung damage
a bacterium called Mycobacterium tuberculosis
What are the symptoms/effects of
malaria?
and what pathogen causes this?
damage to red blood cells and (in severe cases) to the liver
a protist
What are the symptoms/effects of
stomach ulcers?
and what pathogen causes this?
stomach pain, nausea and vomiting
a bacterium called Helicobacter pylori
What are the symptoms/effects of
ebola?
and what pathogen causes this?
haemorrhagic fever ( afever with bleeding)
ebola virus
What are the symptoms/effects of
chalara ash dieback?
and what pathogen causes this?
leaf loss and bark wounds
a fungus that infects ash trees
How does
cholera spread?
and how can you reduce/prevent transmission?
via contaminated water sources
make sure that people have access to clean water supplies
How does
tuberculosis spread?
and how can you reduce/prevent transmission?
through air when infected individuals cough
infected people should avoid crowded public spaces, practic good hygiene and sleep alone
their homes should also be well-ventilated
How does
malaria spread?
and how can you reduce/prevent transmission?
mosquitos act as animal vectors
(they pass on the protist to humans but don’t get the disease themselves)
use mosquito nets and insect repellent to prevent mosquitos carrying the pathogen from biting people
How do
stomach ulcers spread?
and how can you reduce/prevent transmission?
oral transmission
(e.g. swallowing conaminated water or food)
have clean water supplies and hygienic living conditions
How do
ebola spread?
and how can you reduce/prevent transmission?
via bodily fluids
isolate infected individuals and sterilise any areas where the virus may be present
How do
chalara ash dieback spread?
and how can you reduce/prevent transmission?
it is carried through the air by the wind
(also spreads when diseased ash trees are moved between areas)
remove young, infected ash trees and replant with different species
restrict the import or movement of ash trees
Describe the
lytic pathway.
(of viruses) (4 steps)
- The virus attaches itself to a specific host cell and injects it genetic material into the cell.
- The virus uses proteins and enzymes in the host cell to replicate its genetic material and produce the components of new viruses.
- The viral components assemble.
- The host cell splits open, releasing the new viruses, which infect more cells.
Describe the
lysogenic pathway.
(of viruses) (3 steps)
- The injected genetic material is incorporated into the genome (DNA) of the host cell.
- The viral genetic material gets replicated along with the host DNA every time the host cell divides - but the virus is dormant and no new viruses are made.
- Eventually, a trigger causes the viral genetic material to leave the genome and enter the lytic pathway.
Define
STI.
an infection that is spread through sexual contact
What is
Chlamidya?
and what effect does it have?
a type of bacterium (that behaves similarly to a virus as it can only reproduce inside host cells)
it can result in infertility
How can the
spread of chlamidya be reduced?
(3)
- wearing a condom during sex
- screening indivudals so that they can be treated for the infection
- avoid sexual contact
What is
HIV?
and what effect does it have?
Human Immunodeficiency Virus
it kills white blood cells and eventually leads to AIDS
What is
AIDS?
Acquired Immune Deficiency Syndrome, when the infected person’s immune system deteriorates and eventually fails - causing the person to be very vulnerable to infections by other pathogens
How is
HIV spread?
and how can transmission be prevented? (3)
via infected bodily fluids
(e.g. blood semed, vaginal fluids)
- use a condom when having sex
- avoid sharing needles
- screening
What are some
physical plant defences?
and how do these work? (2)
- Waxy cuticle - stops pathogens from entering them or pests damaging them. Also stops water collecting on the leaf, which could reduce the risk of infection by pathogens that are transferred between plants in water.
- Cell walls - form a physical barrier against pathogens that make it past the waxy cuticle.