B3 - Pathogens

What is a pathogen?

A microorganism that causes infectious disease.

Name four types of pathogens.

Bacteria, viruses, protists, fungi.

What are communicable diseases?

Diseases that spread from person to person and are infectious.

How do bacteria cause illness in the body?

Bacteria reproduce rapidly and release toxins that damage tissues and make us ill.

How quickly can bacteria divide under ideal conditions?

Every 20 minutes.

Give an example of a bacterial disease mentioned.

Food poisoning caused by certain bacteria.

How many people in the UK get food poisoning from bacteria each year?

Around 300,000 people.

What is a toxin?

A harmful chemical released by bacteria that damages tissues.

How do viruses cause illness?

Viruses invade host cells, reproduce inside them, damaging or killing the cells when new viruses burst out.

What is a key difference between bacteria and viruses?

Bacteria can reproduce by themselves, viruses can only reproduce inside a host cell.

Give an example of a virus that can lead to AIDS.

HIV.

How are pathogens spread through the air?

By water droplets expelled when people cough or sneeze, e.g., influenza.

How can pathogens spread through water?

By drinking polluted water contaminated with sewage, e.g., cholera.

How can pathogens spread by direct contact?

Through sharing infected needles or sexual contact, e.g., HIV.

Name one way basic hygiene reduces the spread of pathogens.

Washing hands before eating removes pathogens.

How does clean drinking water reduce pathogen spread?

Water treated with chlorine kills microbes, preventing diseases.

How can reducing direct contact between individuals reduce pathogen spread?

Using condoms reduces HIV spread; isolating infected patients prevents transmission.

Why are patients with highly infectious diseases isolated?

To prevent the pathogen from spreading to others.

How does vaccination reduce the spread of pathogens?

It protects individuals and reduces transmission in the population.

What is an example of a disease spread by air droplets?

Influenza.

What is an example of a disease spread by polluted water?

Cholera.

What are the three main ways pathogens spread?

Air (droplets), water (polluted), and direct contact.

Why can't viruses reproduce on their own?

They require a host cell to reproduce.

What happens to a host cell when a virus leaves it?

The cell bursts open and dies.

What does HIV stand for?

Human Immunodeficiency Virus.

What does AIDS stand for?

Acquired Immunodeficiency Syndrome.

Why is it important to practice good hygiene?

To reduce the chance of catching or spreading pathogens.

What chemical is added to UK drinking water to kill microbes?

Chlorine.

What method reduces spread of HIV during sexual intercourse?

Using condoms.

Name a highly infectious disease where patients are isolated.

Ebola.

What is the main function of toxins released by bacteria?

To damage tissues and cause illness.

How does rapid bacterial reproduction contribute to illness?

It increases the number of bacteria and toxin production quickly.

What is the role of water droplets in spreading pathogens?

They carry pathogens through the air to new hosts.

What is the difference between communicable and non-communicable diseases?

Communicable diseases are infectious and spread between people; non-communicable diseases are not infectious.