biology - Disease, Defence & Treatment Flashcards
A micro-organism that causes disease.
Pathogen
A protein originating on a cell surface that acts as a marker to other cells.
Antigen
An organism too small to be seen with the naked eye.
Micro-organism
A protein, secreted by lymphocytes that neutralises toxins.
Antitoxin
A type of white blood cell that detects specific antigens.
Lymphocyte
A micro-organism that has a cell wall, but no nucleus.
Bacterium
An illness
Disease
A specific protein (produced by a lymphocyte) that attaches to an antigen.
Antibody
Bacteria that are no longer killed by an antibiotic
Antibiotic resistant
Can be passed from person to person.
Communicable
The ability to produce antibodies against a specific pathogen so quickly that symptoms are not experienced.
Immunity
A chemical taken in a drugs trial that has no effect on the organism.
Placebo
The community of micro-organisms occurring naturally on the skin surface.
Skin flora
A type of white blood cell that engulfs/ingests non-self material.
Phagocyte
An injection used to provide immunity to a particular disease.
Vaccination
name the 7 parts in a bacterium
DNA,pili, fllagellum, cell membrane, cytoplasm,plasmid, cell wall
name the 4 parts in a virus
antigens, DNA , protein coat, envelope
DNA and RNA are types of nucleic acid. Why does the position of DNA in a bacterium put it in a separate Kingdom to other single celled organisms?
In bacteria, the nucleic acid is not inside a nucleus
Which two structures bacteria may allow them to move?
Flagella and pili
Which structures in bacteria also occur in plant cells?
cell wall (but not made of cellulose), cytoplasm, cell membrane
Which structure in a virus allows it to reproduce?
nucleic acid
Why is a virus not given a binomial name (genus & species)?
It is not a living organism (is not made up of cells)
What is meant by immunity?
The ability to produce antibodies against a specific pathogen so quickly that symptoms are not experienced.
Where are antibodies produced?
Inside lymphocytes
Explain why antibodies were produced more quickly after a second infection of the same disease.
There were lots of specific memory cells already in the blood, so these were able to detect the pathogen quickly, so antibodies were produced more quickly.
Suggest why the person did not become ill after the second infection.
Antibodies were produced so quickly that they increased above the immunity level before the pathogen could replicate inside the body and cause symptoms of the disease.
what is a non-specific response?
The non-specific response involves destroying all non-self material in the same way
what is a specific response
The specific response involves producing lymphocytes against specific antigens (so is more targeted)
explain how som,e parts of the blood can help protect the body from infection at the site of a cut.
- Platelets form a blood clot which seals the wound/stops the bleeding, and to prevent entry of microbes/bacteria
- White blood cells/phagocytes (ingest/engulf) microbes/bacteria, then produce antibodies which inactivate certain bacteria/microbes/viruses
- White blood cells/lymphocytes produce antitoxins which inactivate/counteract toxins released by bacteria/microbes.
explain how antigens from the surface of pathogens stimulate a specific immune response with a lasting effect on the body.
- Antigens (are proteins) on the surface of cells (which act as markers), (There are different types of) lymphocyte, (each with receptors) that detect a specific type of antigen.
- (If the lymphocyte detects complementary antigens) it clones itself/divides by mitosis to produce many plasma cells and memory cells.
- Plasma cells secrete millions of specific antibodies which bind to the antigens, causing the pathogens to clump together preventing them from reproducing.
- (Memory cells remain in the body providing immunological memory.) If the same type of pathogen infects the body in future, memory cells respond quickly, producing millions more antibodies and more memory cells.
- This secondary response is faster and greater than the primary/first response; antibodies are produced more quickly and in greater numbers. The pathogens are destroyed before symptoms are experienced / this provides immunity against that pathogen
Who discovered antibiotics?
Alexander Flemming
The name of the antibiotic discovered by Alexander Flemming?
Penicillin
What do antibiotics do?
Kill bacteria
Who made penicillin into medicine?
(Howard) Florey & (Ernst) Chain
Why can tonsillitis can be treated with antibiotics, but influenza cannot?
Tonsillitis is caused by a bacterium (which can be killed with antibiotics);
Influenza is caused by a virus (which is not affected by antibiotics)
What is the effect of the over-use of antibiotics?
Increase in antibiotic-resistant strains of bacteria.
Give an example of an antibiotic resistant bacterium.
MRSA
Name three ways to reduce the spread of antibiotic resistant bacteria.
Use of alcohol gels (hand santiser) and regular handwashing.
Thorough cleaning of hospital wards
Careful prescription of antibiotics (to avoid further resistance)
List 6 ways in which communicable diseases spread.
Direct contact
Aerosol (e.g. from coughs & sneezes)
Body fluids (e.g. blood, semen)
Water
Insects
Contaminated food
What forms a scab over a cut?
Platelets
Name two main types of white blood cell.
Phagocyte
Lymphocyte
Name five ways of preventing disease.
Good hygiene
Clean water
Improved diet
Vaccination
Safer sex (i.e. using condoms)
Name the English doctor who first used vaccination to treat a patient in the UK.
Edward Jenner
