Communicable Disease Biology Flashcards
What are communicable diseases?
Diseases caused by pathogens that can be transmitted from one individual to another
Define ‘pathogens’.
Microorganisms that cause diseases
State the four types of pathogens.
Bacteria, viruses, protists, fungi
How do bacteria make you ill?
Reproduce rapidly and damage cells + Produce toxins
How do viruses make you ill?
Produce inside body cells, causing damage
How can pathogens be spread?
By air/droplet infection, direct contact, water
state one method to prevent the spread of disease.
Isolation; Maintain good hygiene; Destroy vectors; Vaccination
How can bacterial diseases be treated?
Antibiotics
Name a fungal disease in humans.
Athlete’s foot
Which pathogen causes rose black spot?
Fungi
Which pathogen causes malaria.
Protists
How is malaria spread?
By female Anopheles mosquitoes
How does malaria affect the body?
Damages blood and liver cells
How can the spread of malaria be stopped?
Use mosquito nets; Use insecticides; Remove standing water; Take antimalarial drugs
What are the non specific defense mechanisms of the body against pathogens (4)
Skin
Nose
Trachea and bronchi
Stomach
How does the skin protect against pathogens(3)
Acts as a barrier
Produces antimicrobial secretions
Covered with microorganisms that also act as a barrier
How does the nose protect against pathogens
Full of hairs that produce mucus that traps particles in air that may carry pathogens
How does the trachea and bronchi protect against pathogens
Secrete mucus that traps pathogens, cilia transport mucus to stomach
How does the stomach protect against pathogens
Contains acid which kill pathogens that are transported to it in food or in mucus
What is the role of the immune system
To destroy pathogens that make it past the first line of defence
What are the types of white blood cells
Phagocytes
Lymphocytes
How do lymphocytes protect against disease
Antibody production - Target particular pathogen’s antigen, bind to them and destroy them. A unique antibody is used for each antigen
Antitoxin production - Bind to toxins produced by pathogens and stop them from causing damage
What is a vaccine
dead or inactive pathogenic material used in vaccination to develop immunity to a disease in a healthy person
Describe the process involved in vaccination (4)
Small amounts of dead or inactive pathogen are injected into body
Antigens in vaccine stimulate white blood cells into making antibodies
Blueprints for those antibodies used for that pathogen are stored in memory cells
In future infections antibody can be quickly produced to quell infection
What are antibiotics
Drugs used to treat bacterial diseases
How do antibiotics work
Destroy bacterial cells without damaging anything else
Why can’t antibiotics treat viral diseases
Because antibiotics only destroy bacteria
Why is it difficult to treat viral diseases
Because the viruses hide inside the patients cells, meaning the patients cells must be damaged to damage the virus
What are painkillers
Drugs that treat the symptoms of a disease to increase quality of life but don’t actually treat the disease
State the order of drug trialing (5)
Scientists user computer models to identify molecules to target
Drug discovered, usually using computer models
Preclinical trials (Cell colonies, tissues, Live animals)
Clinical trials (1 - small healthy group(low dosage), 2 - large healthy group(medium dosage), 3 small unhealthy(low dosage)
Licensing
What is a double blind trial
One in which neither the patient nor the conductor know who is given the real drug and who is given the placebo in an attempt to eliminate observer bias
communicable disease
disease that is transmitted from one individual to another by pathogens
non communicable disease
disease that is not transmitted from person to person i.e cancer, defects, radiation, natural causes
