B3- Infection&Response Flashcards
Define the term communicable disease.
Infectious diseases that can be spread.
Give four examples of pathogens.
Virus, fungi, protists, bacteria.
What are the three ways that pathogens can be spread?
Water, air, direct contact.
Give examples of a disease that is caused by each pathogen.
Viruses- TMV, HIV, Measles.
Bacteria – Salmonella, Gonorrhoea.
Fungi – Rose black spots.
Protists- Malaria.
How does the body prevent pathogens from entering?
Skin, Stomach acid, Mucus and hairs in the nose, Mucus in the trachea, Cilia in trachea and bronchi.
Once pathagons enter the body, how do white blood cells respond?
1) . Phagocytosis – Engulf and digest pathogens.
2) . Produce proteins called antibodies.
3) . Produce antitoxins.
What is a vaccine?
A dead/ inactive pathogen.
What are some advantages of vaccination?
Helps to control spread many communicable diseases.
If a large number of population has the vaccination, outbreaks of the disease can be prevented.
What is herd immunity?
The protection given to a population against an outbreak of a specific disease when a very high percentage of the population has been vaccinated against it.
What is the difference between phagocytes and lymphocytes?
Phagocytes are white blood cells which circulate in the body. They engulf pathogens and then use a range of enzymes inside the cell to destroy the pathogen.
Lymphocytes recognise specific molecules on the surface of pathogens call antigens.
What is the difference between painkillers and antibiotics?
Painkillers are drugs that relieve symptoms.
Antibiotics kill bacteria causing the infection without killing body cells.
Can antibiotics kill viruses?
No because viruses reproduce using your own body cells.
What is antibiotic resistance?
An example of natural selection. In a large population of bacteria, there may be some that are not affected by an antibiotic. They survive and reproduce – producing more bacteria that are not affected by the antibiotic.
What are the roles of aspirin and digitalis and where are they found?
Aspirin is used as a painkiller and to lower fever. It is developed from willow.
Digitalis is used to treat heart conditions. It is developed from foxgloves.
What are the main stages in drug testing?
1) . Pre-clinical trials were trucks are tested on human cells and tissues in a lab.
2) . Then tests on animals are carried out to check effiency/toxicity.
3) . Clinical trials – testing on human volunteers to check side-effects.
4) . The truth is them tested on humans with the illness – to find optimum dose.
5) . Double blind trials are carried out followed by peer review.
