Use of drugs against infecting micro-organisms

Question 1

What are antibiotics?

Answer 1

Antibiotics are substances that fight infections caused by bacteria. Different antibiotics are developed to treat different infections. Antibiotics cannot fight infections caused by viruses.

Question 2

In what cases are antibiotics necessary?

Answer 2

When bacteria gets past all the body’s defences because they may have reproduced so fast that the immune system cannot deal with the extent of the infection or produced a toxin that could cause permanent damage to the body before the immune system can be effective.

Question 3

How do antibiotics work? (3)

Answer 3

• They prevent the proper formation of the cell wall. This will cause the bacteria to become unstable and eventually burst e.g. Penicillin
• They damage the cell membrane. This will change its permeability causing the cell to leak its contents leading to its death
• Affect RNA and prevent protein synthesis. This will prevent the bacteria forming cell proteins and enzymes causing its death.

Question 4

What are the side effects of antibiotics? (4)

Answer 4

• Stomach Cramps
• Diarrhoea
• Vaginal yeast infections
• Allergies

Question 5

Define superbugs.

Answer 5

A strain of bacteria that has become resistant to antibiotic drugs.

Question 6

How does Antibiotic resistance happen?

Answer 6

• Bacteria breed very rapidly. As a result bacterial populations become enormous
• Within these populations chance mutations may produce bacteria which are antibiotic resistant, i.e they develop methods to protect themselves against the antibiotic. For example the bacteria may make an enzyme that can destroy the antibiotic, or its cell wall can become resistant to being broken by the action of the antibiotic
• The bacteria with the resistant trait multiplies to produce a fully antibiotic resistant population
• This will force doctors to prescribe another type of antibiotic to help fight the pathogens- which may later gain resistance to the new drug

Question 7

Why do resistant populations develop?

Answer 7

The repeated incorrect use of antibiotics are the primary cause of the increase in drug-resistant bacteria

Question 8

How does repeated use of antibiotics lead to resistant populations?

Answer 8

Every time a person takes antibiotics, sensitive bacteria are killed, but resistant ones may be left to grow and multiply.

Question 9

How does the incorrect use of antibiotics lead to resistant populations?

Answer 9

It contributes towards resistance developing.

Question 10

What are the dangers of antibiotic resistance? (4)

Answer 10

• Illnesses last longer
• More doctor visits and/or longer hospital stays are necessary
• More expensive and toxic medications are needed
• Death

Question 11

What is a vaccine?

Answer 11

It is a suspension of dead, weekend or fragmented micro-organisms or their toxins that will stimulate the growth of antibodies which will induce immunity.

Question 12

Vaccines are given primarily to prevent ____.

Answer 12

Disease

Question 13

What is vaccination?

Answer 13

Also called immunisation, it is a process of giving a person a vaccine, by injection or given orally, to make them immune to a disease.

Question 14

Which part of a pathogen is used in a vaccine?

Answer 14

The vaccine is composed of a protein that resides on the surface of the virus. This strategy can be used when an immune response to one part of the virus (or bacteria) is responsible for protection against disease

Question 15

At one time all antibiotics were made from living organisms. This process, known as ___, is still used in the manufacturing of some antibiotics.

Answer 15

Biosynthesis

Question 16

Natural antibodies are made and secreted by fungi (___) such as ____ (which grows on fruit) and ____ (which grows in the soil).

Answer 16

Moulds
Penicillium
Streptomyces

Question 17

What is required to collect these antibiotics.

Answer 17

Favourable conditions.

Question 18

How is Penicillium made from mould?

Answer 18

• Mould organisms are placed in a suitable medium to which sugar has been added
• This forms a broth that is put into a tank, which is kept at a temperature of 25 degrees celsius and shaken for more than 100 hours.
• The mould organisms grow rapidly in this warm soup, producing penicillin as they multiply
• The penicillin is later extracted.

Question 19

What do all types of penicillin molecules have?

Answer 19

They have an identical chemical nucleus called a ring. the chemical chain that is attached to the ring is different in each type of penicillin.

Question 20

What do medical biotechnologists do to produce synthetic antibiotics?

Answer 20

They change the atoms in the molecules of the chain to devise synthesise antibiotics with potentially different effects on different organisms

Question 21

How is insulin produced?

Answer 21

By Recombinant DNA Technology.

Question 22

How is recombinant insulin produced?

Answer 22

To make insulin the gene that is responsible for its production is spliced into micro-organisms such as yeast or bacteria. these are then placed in suitable medium in which they will grow and reproduce rapidly, producing large quantities of insulin.

Question 23

Define Recombinant.

Answer 23

Resulting from the splicing of DNA fragments