B5 & B6 - Communicable diseases & Preventing and treating disease 1️⃣✅ Flashcards
What is a communicable disease?
A disease that can be transmitted from one organism to another.
What is a pathogen?
A microorganism that can cause disease
Name 4 types of pathogen.
Fungi, bacteria, virus & protists
How can pathogens spread?
Air, water & direct contact
How do bacteria make you feel ill?
By producing toxins that damage cells
How do viruses make you ill?
By reproducing rapidly inside cells & damaging or destroying them
Name 3 examples of a viral disease.
HIV, measles & tobacco mosaic virus
Name 2 examples of a bacterial disease.
Salmonella & gonorhoea
Name 4 methods of controlling the spread of communicable diseases.
Good hygiene, vaccination, isolating from infected individuals & controlling vectors
What is a vector?
A organism that transmits a pathogen e.g. aphids
What is an example of a fungal disease in plants?
Rose black spot - spread by water and wind, affects plant growth by reducing plants ability to photosynthesise.
What are 3 mechanical defences that protect plants?
Thorns/hairs, mimicry & droopy leaves
What are 3 physical defences that protect plants.?
Cellulose cell walls, tough waxy cuticles on leaves & bark on trees
What are 2 chemical defences that protect plants?
Poison & anti microbial chemicals
What are examples of the bodies first line of defence against pathogens?
Skin, nasal hairs, eyelashes & mucus in the nose
Give 3 jobs of white blood cells
phagocytosis, producing antibodies & producing antitoxins
What happens during phagocytosis?
A phagocyte is attracted to the area of infection, marked by an antibody. It then engulfs the pathogen, and releases enzymes to digest the pathogen
What are antigens?
Antigens are proteins on the surface of a pathogen.
Why are antibodies a specific defence?
Antibodies have to be the correct shape for a pathogen’s unique antigens, so they target a specific pathogen
What is the function of an antitoxin?
To neutralise toxins produced by pathogens by binding to them
What does a vaccine contain?
Small quantities of a dead or inactive form of a pathogen to stimulate white blood cells to produce antibodies
What is herd immunity?
When most of the population is vaccinated against disease, meaning its less likely to spread
What is an antibiotic?
Drugs that kill bacteria not viruses
What happens in the pre-clinical stage of a drug trail?
The drug is tested on cells, tissues and live animals
What is a placebo?
Medicine with no effect that is given to patients instead of the real drug in the trial