Biology Chapter 7 Disease Flashcards
What is a communicable disease
A disease that can be passed from one organism to another
What microbes can cause disease
bacteria
virus
fungi
Name 2 bacterial diseases
state how they can be spread
How can they be treated
Salmonella - undercooked meat (chicken)
Prevent - cook meat thoroughly
Tuberculosis - droplets in air
Treat - antibiotics
Chlamydia - sexual contact
Treat - antibiotics
Name 2 viral diseases
How spread
How prevent/treat
HPV - sexual contact
Prevent - vaccination
HIV - sexual contact/blood mixing eg blood transfusion or sharing needles
Treat - drugs to control
Flu and Cold
- droplets in air
Flu vaccine
Name 2 fungal diseases
How spread
how treat
Athletes food - skin contact
treat - antifungal cream
Potato blight - spread through air
Treat - spray plants with fungicide
How does the body defend against infection
Skin acts as barrier
Form blood clots and scab at sight of a cut
Mucous membranes (eg in throat) trap microbes
What are the 2 different types of white blood cells
Phagocytes
lymphocytes
What is found on the surface of cell membrane that the white blood cells recognize as being foreign
Antigens
How do white blood cells destroy microbes
Lymphocytes produce ANTIBODIES that have a shape complementary to antigen on microbe
Antibodies cause the microbes to clump together
This allows the phagocytes to engulf and digest the microbes all clumped together
Memory lymphocytes stay in blood
What is the job of memory lymphcytes
If reinfected with same microbe memory lymphocytes will respond quickly and produce large numbers of antibodies so microbe destroyed before getting symptoms of disease
If the levels of antibodies is high what is the person said to be
immune to the disease
What is the name given to the type of immunity you get from having had an infection
Active immunity
What is a vaccine
Dead or inactive form of the microbe - will stimulate the white blood cells to produce antibodies (lymphocytes) and make you immune
What is meant by passive immunity
When a person is ill and is given a large amount of antibodies in hospital - levels of antibodies is high but drops quickly as the body has no memory lymphocytes.. They do not have long term immunity to the disease
Why would a person be given a booster vaccine
If the levels of antibodies drop below immunity level the booster will cause the body to produce antibodies to a high level and person becomes immune
What is an antibiotic
A chemical produced by fungus to kill bacteria
name an antibiotic
Penicillin
Who discovered penicillin
Fleming
Who developed penicillin
Florey and Chain
Higher tier
What are the problems with overuse of antibiotics
Some bacteria mutate and develop resistance to antibiotic
If they develop resistance to many antibiotics they become superbugs e.g MRSA and few antibiotics able to destroy them
What are superbugs a problem in hospitals
People in hospitals have low immunity levels already
May have open cuts so microbes can enter them
Can spread from patient to patient easily
How can hospitals try and prevent MRSA spreading
Good hygiene
isolate patients with MRSA
not overuse antibiotics
How are drugs developed
- In vitro testing - on cells/tissue to see if cause harm
- Animal testing - to see if any side effects (ethical issues with this)
- Clinical trials - on healthy volunteers to see if any side effects
Then on patients to work out if it works and get the correct dose to give patients
4 License the drug for distribution to all
What is a recreational drug
alcohol or cigarettes
drug taken for non medical reasons
Alcohol can damage what organ
Liver
How can alcohol affect a foetus in a pregnant woman
affect development of foetus
What is binge drinking
Drinking large amounts of alcohol in one go
What can a person do to try and prevent liver damage/over drinking
Have a few nights a week not drinking
Drinking low alcohol or non alcohol drinks
What are the 3 main ingredients of a cigarette
tar, nicotine, carbon monoxide
How does tar damage a person
can cause bronchitis, emphysema or lung cancer
How does carbon monoxide affect a person
it binds to red blood cells and reduces the amount of oxygen a person can carry in blood
what is nicotine
the addictive drug in cigarettes
will affect/increase heart rate
