Health, disease and the development of medicines (5) Flashcards
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 difference between communicable and noncommunicable diseases?
Communicable diseases are ones which can be spread between individuals while noncommunicable diseases can’t be transmitted between individuals e.g. cancer and heart disease.
Why does the presence of a disease lead to a higher susceptibility to other diseases?
Because you body (immune system) is weakened when it fights off diseases making it less able to fight off others.
What is a pathogen?
A disease-causing organism including viruses, bacteria, fungi and protists.
What are some common infections?
Cholera - bacteria - causes diarrhoea.
Tuberculosis - bacteria - lung damage.
Malaria - protist - damage to red blood cells and liver.
Stomach ulcers - bacteria - stomach pain, nausea and vomiting.
Ebola - virus - hemorrhagic fever.
Chalara ash dieback - fungus - leaf loss and bark lesions.
How are the pathogens spread and how can you reduce the spread of the pathogens?
Cholera - via contaminated water - people have access to clean water supplies.
Tuberculosis - through air - infected people avoid crowded places, practise good hygiene and make sure their homes are well ventilated.
Malaria - mosquitoes act as vectors passing on the protist to humans - mosquito nets and insect repellant.
Stomach ulcers - oral transmission - washing your hands after going toilet and don’t touch other people’s food.
Ebola - via bodily fluids - isolating infected individuals and sterilising areas where the virus may be present.
Chalara ash dieback - through air by wind - removing young infected ash trees and restricting the movement of ash trees.
What is the lytic pathway?
The virus attaches itself to the host cell and injects its genetic material inside it.
The virus uses proteins and enzymes in the host cell to replicate its genetic material and produce components of new viruses.
The viral components assemble.
The host cell lyses releasing the new viruses.
What is the lysogenic pathway?
The injected genetic material is incorporated into the genome.
The viral genetic material gets replicated along with the host DNA everytime the host cell divides.
The virus is dormant and no new viruses are made.
A trigger causes the viral genetic material to leave the genome and continue the lytic pathway.
How are STIs transmitted and how can the spread be reduced or prevented?
Chlamydia is a bacterium which can cause infertility in men and women. The spread can be reduced by wearing a condom, screening individuals so they can be treated or avoiding sexual contact.
HIV kills white blood cells and leads to AIDS where the immune system deteriorates. HIV is spread through the contact of bodily fluids. The spread can be reduced by wearing a condom during sex, taking medicine, screening and proper treatment.
What do antibiotics do?
Treat bacterial infections as the inhibit the cell processes of bacteria but not the host cell.
What are the aseptic techniques used in culturing microorganisms?
Petri dishes and growth medium must be sterilised by placing them in an autoclave (high pressure steam and high temperature.
Inoculating loop is passed through a flame.
Keep petri dishes and vials covered.
What are the stages to medicine development?
Stage 1:
Pre-clinical stage, tested on cells and tissues to see if the medicine can get into cells and have the required effect and any side effects.
Stage 2:
Medicine is tested on animals to see if it works on a whole body.
Stage 3:
Small clinical trial, tested on a small number of healthy people to check that it is safe and the side effects are small.
Stage 4:
Large clinical trial, tested on many people with the disease to work out the correct dose and to check for any side effects.
