Preventing and treating disease 12.7

Question 1

what are non-communicable diseases and what are some examples

Answer 1

non-communicable diseases cannot be passed from one person to another. They include heart disease, most types of cancer and many diseases of the nervous, endocrine and digestive systems.

Question 2

What are the ways you can achieve immunity

Answer 2

• Natural immunity
• Artifical immunity

Question 3

Why is natural active immunity

Answer 3

When you meet a pathogen for the first time, your immune system is activated and antibodies are formed, which results in the destruction of the antigen. The immune system produces T and B memory cells so if you meet a pathogen for a second time, your immune system recognise the antigens and can immediately destroy the pathogen, before it causes disease symptoms. This is known as natural active immunity. It is known as active because the body has itself acted to produce antibodies and/or memory cells.

Question 4

What are the types of natural immunity

Answer 4

• Natural active immunity
• Natural passive immunity

Question 5

What is natural passive immunity

Answer 5

A type of immunity that occurs when a person is given antibodies rather than making them through there own immune system.
such as when babys get first milk of mothers (colostrum) which is high in antibodies

Question 6

what are the types of artifical immunity

Answer 6

• Artifical passive immunity
• Artifical active immunity

Question 7

define artifical passive immunity

Answer 7

• antibodies formed in one individual, extracted and then injected into another individual

Question 8

What is artifical active immunity

Answer 8

In artificial active immunity the immune system of the body is stimulated to make its own antibodies to a safe form of an antigen (a vaccine), which is injected into the bloodstream (vaccination). The antigen is not usually the normal live pathogen, as this could cause the disease and have fatal results.

Question 9

what are the steps of how a vaccine works to provide artifical active immunity

Answer 9

1)The pathogen is made safe in one of a number of ways so that the antigens are intact but there is no risk of infection
2)Small amounts of the safe antigen, known as the vaccine, are injected into the blood.
3)The primary immune response is triggered by the foreign antigens and your body produces antibodies and memory cells as if you were infected with a live pathogen
4)If you come into contact with a live pathogen, the secondary immune response is triggered and you destroy the pathogen rapidly before you suffer symptoms before you suffer symptoms of the disease.

Question 10

what can vaccines contain

Answer 10

• killed or inactivated bacteria and viruses, for example whooping cough
• attenuated (weekend) strains of live bacteria or viruses, for example, rubella, BCG against TB, polio (vaccine taken orally)
• toxin molecules that have been altered and detoxified for example, diphtheria, tetanus
• isolated antigens extracted from the pathogen, for example the influenza vaccine
• genetically engineered antigens, for example, the hepatitis B vaccine.

Question 11

what is an epidemic

Answer 11

an epidemic is when a communicable disease spreads rapidly to a lot of people at a local or national level

Question 12

What is a pandemic

Answer 12

A pandemic is when the same disease spreads rapidly across a number of countries and continents.

Question 13

What is heard immunity

Answer 13

When a significant number of people in the population have been vaccinated, this gives protection to the who do not have immunity. This is known as herd immunity, as there is minimal opportunity for an outbreak to occur.

Question 14

what are some disease that we do not have vaccines for

Answer 14

• Malaria - plasmodium, the protoctista that causes malaria. It is very evasive - it spends time inside the erythrocytes so it is protected by self antigens from the immune system, and within an infected individual its antigens reshuffle
• Hiv, the human immunodeficiency virus that causes AIDs. It enters the macrophages and T helper cells, so it has disabled the immune system itself

Question 15

Where does penicillin come from

Answer 15

It comes from mould, famously discovered by Alexander Fleming in 1928. When he found it growing on bacterial cultures and saw what the mould did.

Question 16

what is Pharmacogenetics

Answer 16

The science of interweaving knowledge of drug actions with personal genetic material is known as Pharmacogenetics
for example, in approximately 30% of all breast cancers there is a mutation in the HER2 gene. The activity of this gene can be shut down by specific drugs. By analysing breast tutors and treating those which have this mutation with the relevant drugs, doctors can reduce the deaths from HER2 breast cancer by up to 50%.

Question 17

What is synthetic biology and how can it be used for medicinal uses

Answer 17

Using the techniques of genetic engineering, we can develop populations of bacteria to produce much needed drugs that would otherwise be too rare, too expensive or just not available. Synthetic biology enables the use of bacteria as biological factories. Mammals have also been genetically modified to produce much needed therapeutic proteins in their milk.

Nanotechnology is another strand of synthetic biology, where ting, non-natural particles are used for biological puporses - for example to deliver drugs to very specific sites within the cells of pathogens or tumours.

Question 18

what is selective toxicity

Answer 18

• when antibiotics interfere with the metabolism of the bacteria without affecting the metabolism of the human cells

Question 19

what are the stages of antibiotic resistant bacteria forming

Answer 19

Question 20

What measures can be put in place to reduce antibiotic-resistant infections in the long term

Answer 20

• minimising the antibiotics and ensuring that every course of antibiotics is completed to reduce the risk of resistant individuals serving and developing into a resistant strain population
• good hygiene in hospitals, care home and in general - this has a major impact on the spread of all infections, including antibiotic-resistant strains.

Question 21

what are the disadvantages of passive artifical immunity

Answer 21

• immunity given does not last long

Question 22

Give an example of where artifical passive immunity is used

Answer 22

• people infected with tetanus will be injected with tetanus antibodies extracted from horses