Microbes and Diseases

Questions - write the answers in your book1. Name 3 things which can damage your health.2. There are millions of bacteria everywhere - in the air, water, soil and you. Some are important and are useful (e.g. production of yoghurt), but others cause disease. List 3 ways in which bacteria can enter your body.3. Explain why it is important to cover your mouth or nose when you cough or sneeze.4. When bacteria enter our body and start to multiply, what do we say we have?5. Why shouldn’t we eat food which is undercooked?6. Bacteria can get into drinking water and make you ill when you drink it. Which disease can be spread in this way?

Microbes or micro-organisms can only be seen using a m .

They can infect our bodies and cause d .

food poisoning colds flu chicken pox whooping cough German measles tetanus sore throats polio cold sores foot and mouth disease AIDS cholerayoghurt microscope cheese harmful disease poisons body antibiotics small

Bacteria Viruses single celled organism

are not always h . (useful for making c and

y and for decomposing sewageand dead plants and animals)

grow and reproduce inside your b . can release poisons (toxins) or damage cells are destroyed by a . numbers can double every 20 mins Examples of diseases they cause:

f o od po

t

w cough

s t

ch

are not cells - contain genetic information are very s . infect cells – don’t survive long out of body multiplies by making copies of itself inside

the cell then bursts out of cell killing it andreleases lots of viruses to infect more cells

can release p making you feel ill antibiotics don’t affect them Examples of diseases they cause:

co

f

c p

G m

p

c s

A

foot and

Microbes and Diseases

Questions - write the answers in your book1. Name 3 things which can damage your health.2. There are millions of bacteria everywhere - in the air, water, soil and you. Some are important and are useful (e.g. production of yoghurt), but others cause disease. List 3 ways in which bacteria can enter your body.3. Explain why it is important to cover your mouth or nose when you cough or sneeze.4. When bacteria enter our body and start to multiply, what do we say we have?5. Why shouldn’t we eat food which is undercooked?6. Bacteria can get into drinking water and make you ill when you drink it. Which disease can be spread in this way?

Microbes or micro-organisms can only be seen using a m .

They can infect our bodies and cause d .

chicken pox whooping cough German measles sore throats AIDS cholerayoghurt microscope harmful disease poisons body antibiotics small

Bacteria Viruses single celled organism

are not always h . (useful for making y and for

decomposing sewage grow and reproduce inside your b . can release poisons (toxins) or damage cells are destroyed by a .

Examples of diseases they cause:

f o od poisoning

w cough

s ore t

are not cells are very s . infect cells makes copies of itself inside the cell

can release p making you feel ill antibiotics don’t affect them Examples of diseases they cause:

colds and flu

chicken p

G m

cold sores

A

Antibiotics

Antibiotics are substances which can kill bacteria. Alexander Fleming was a Scottish scientist who studied the bacteria that stopped soldiers wounds from healing. In 1928 he discovered the first antibiotic by accident! He noticed some mould (fungus) growing on jelly which had stopped the bacteria growing on it. The mould was called Penicillin notatum and it produced a substance which killed bacteria. From this discovery Howard Florey then used this substance - penicillin to treat patients.

Why can’t antibiotics be used to treat the common cold?

Fighting disease

Your body has a defence system against microbes. You have a protective wrapping - your s______.

Your body recognises ‘enemy’ microbes which do get in and fights against them. It is the job of the i___________ system to fight disease.

Some types of white blood cells surround the microbes and destroy them by ‘eating’ them.

Another type of white blood cell makes antibodies. Each type of antibody is designed to attack and kill a certain type of microbe.

Questions - write the answers in your book.1. If you catch a disease like measles, you don’t get it again - you become immune. Explain how you think you become immune to diseases.2. You can become immune by vaccination. A vaccine is a weak or dead form of the disease microbe. Try to explain how vaccination works.3. Your body can make millions of different antibodies. Why do you think this is?