B2 Flashcards
What is a pathogen?
A microorganism that causes disease
Name 4 different types of pathogens
Protists, Fungi, Bacteria, Viruses
What are bacteria?
They are prokaryotic, very small cells that reproduce rapidly, and produce toxins that damage your cells and tissues
What are protists?
They are eukaryotic, single-celled organisms that vary in size
What are fungi?
Some are single-celled, some are bodies. They grow and penetrate human skin/surface of plants causing diseases. They also produce spores which can spread to other organisms
What are viruses?
They are not cells. They are INCREDIBLY small, and replicate themselves inside the infected organism’s cells, causing them to burst and release more viruses
Describe 2 ways white blood cells protect your body from pathogens
Consuming them- phagocytes have a flexible membrane and lots of enzymes. This allows them to engulf and digest the pathogen.
Producing antibodies- white blood cells that detect foreign antigens can create antibodies that lock onto and disable the pathogen, making it easier for the phagocyte to engulf them
What is a memory cell?
White blood cells that stay around in the blood after a pathogen has been fought off. If the same pathogen returns, the memory cells will trigger the rapid production of the same antibodies needed to destroy it, meaning you will not get the disease
Summarize the process of making monoclonal antibodies
An animal is injected with the antigen you want to target. The animal then produces antibodies to counteract the antigen. A blood sample is then taken from the animal and the correct antibody is extracted. The antibody is fused with tumour cells (which can divide many times) and is then cloned many times in a lab
What is an incubation period?
The time from the moment of infection until signs and symptoms of the disease appear
What are 3 common causes of disease / ill health?
1) Pathogen infection
2) Genetic mutation
3) Environmental factors
What are non-communicable diseases?
Diseases that cannot be passed from one organism to another- they are associated with genetic mutations and environmental factor and they generally last for a long time and progress slowly`
What are communicable diseases?
Diseases that can be passed from one organism to another- they are caused by a pathogen infecting the organism
What are the 7 ways communicable diseases can be spread?
1) Water
2) Air
3) On surfaces
4) Body fluids
5) Animal vectors
6) Soil
7) Food
State 1 human physical defence and how it defends you
The skin is a barrier protecting vulnerable areas from pathogens
State 1 human chemical defence and how it defends you
Saliva contains molecules that kill pathogens that enter the mouth
State 1 human microbial defence and how it defends you
Natural bacteria in the gut will compete with pathogens for necessary survival resources, making it harder for pathogens to survive
State 1 plant physical defence and how it defends the plant
Plant cell walls are a barriers preventing pathogens from entering
Why is preventing pathogens from attacking plants important?
Plants are at the start of most food chains, therefore if many plants are taken out by pathogens, then it will have a negative knock on effect for the rest of the food chain
State 1 feature of a plants immune system
If pathogens manage to bypass the plants physical defences, then the plant can produce antimicrobial substances as a chemical defence