10.1

Diseases and immunity

12 flashcards to master Diseases and immunity

Smart Spaced Repetition

Rate each card Hard, Okay, or Easy after flipping. Your progress is saved and cards are scheduled for optimal review intervals.

Definition Flip

Define a pathogen.

Answer Flip

A pathogen is a disease-causing organism. Examples include bacteria (like *Vibrio cholerae* causing cholera), viruses (like influenza), fungi (like athlete's foot), and protozoa (like *Plasmodium* causing malaria).

Definition Flip

What is a transmissible disease?

Answer Flip

A transmissible disease is a disease in which the pathogen can be passed from one host to another. Examples include influenza, cholera, and athlete's foot. These diseases are spread through various means from an infected individual to a healthy one.

Key Concept Flip

List three ways a pathogen can be transmitted indirectly.

Answer Flip

Pathogens can be transmitted indirectly through contaminated surfaces (

Example: touching a doorknob with flu virus), food (. *Salmonella* in undercooked chicken), animals (. mosquitoes carrying malaria), and air (. droplets containing cold viruses).
Key Concept Flip

Describe the role of skin in body defense.

Answer Flip

Skin acts as a physical barrier, preventing pathogens from entering the body. It also produces oils and sweat which can inhibit the growth of some pathogens.

Example: the epidermis layer provides a tough, waterproof barrier.
Key Concept Flip

Explain the importance of a clean water supply in controlling disease spread.

Answer Flip

A clean water supply prevents the spread of waterborne diseases like cholera, caused by the bacterium *Vibrio cholerae*. Ensuring water is free from pathogens reduces the risk of ingestion and subsequent infection.

Definition Flip

Define active immunity.

Answer Flip

Active immunity is a defence against a pathogen by antibody production in the body. It can occur after natural infection or through vaccination, resulting in long-term protection. An example is the body producing antibodies after contracting measles.

Definition Flip

What are antigens, and what role do they play in immunity?

Answer Flip

Antigens are molecules, often proteins, on the surface of pathogens, which have specific shapes. These shapes trigger an immune response, leading to antibody production.

Example: the influenza virus has antigens that trigger the immune system.
Key Concept Flip

Explain how antibodies work to fight pathogens.

Answer Flip

Antibodies are proteins that bind to specific antigens on pathogens. This binding can directly destroy pathogens or mark them for destruction by phagocytes (white blood cells). Each antibody has a shape complementary to the shape of its antigen.

Key Concept Flip

Outline the process of vaccination.

Answer Flip

Vaccination involves introducing weakened pathogens or their antigens into the body. This stimulates lymphocytes to produce antibodies and memory cells, providing long-term immunity without causing the disease. An example is the MMR vaccine against measles, mumps, and rubella.

Definition Flip

What is passive immunity, and how is it acquired?

Answer Flip

Passive immunity is a short-term defence against a pathogen by antibodies acquired from another individual. This can occur across the placenta from mother to fetus or through breast milk.

Example: a newborn baby receives antibodies from breast milk, protecting it from certain infections.
Key Concept Flip

Why is breastfeeding important for infant immunity?

Answer Flip

Breastfeeding provides infants with passive immunity by transferring antibodies from the mother's milk to the baby. These antibodies protect the infant from infections during the first few months of life.

Example: IgA antibodies in breast milk protect against gut infections.
Key Concept Flip

Explain how *Vibrio cholerae* causes diarrhoea and dehydration.

Answer Flip

The *Vibrio cholerae* bacterium produces a toxin that causes chloride ions to be secreted into the small intestine. This leads to osmotic movement of water into the gut, causing diarrhoea, dehydration, and loss of ions from the blood.

Review the material

Read revision notes with definitions, equations, and exam tips.

Read Notes

Test yourself

Practice with MCQ questions to check your understanding.

Take Quiz
9.4 Blood 11.1 Gas exchange in humans

Key Questions: Diseases and immunity

Define a pathogen.

A pathogen is a disease-causing organism. Examples include bacteria (like *Vibrio cholerae* causing cholera), viruses (like influenza), fungi (like athlete's foot), and protozoa (like *Plasmodium* causing malaria).

What is a transmissible disease?

A transmissible disease is a disease in which the pathogen can be passed from one host to another. Examples include influenza, cholera, and athlete's foot. These diseases are spread through various means from an infected individual to a healthy one.

Define active immunity.

Active immunity is a defence against a pathogen by antibody production in the body. It can occur after natural infection or through vaccination, resulting in long-term protection. An example is the body producing antibodies after contracting measles.

What are antigens, and what role do they play in immunity?

Antigens are molecules, often proteins, on the surface of pathogens, which have specific shapes. These shapes trigger an immune response, leading to antibody production.

Example: the influenza virus has antigens that trigger the immune system.
What is passive immunity, and how is it acquired?

Passive immunity is a short-term defence against a pathogen by antibodies acquired from another individual. This can occur across the placenta from mother to fetus or through breast milk.

Example: a newborn baby receives antibodies from breast milk, protecting it from certain infections.

About Diseases and immunity (10.1)

These 12 flashcards cover everything you need to know about Diseases and immunity for your Cambridge IGCSE Biology (0610) exam. Each card is designed based on the official syllabus requirements.

What You'll Learn

How to Study Effectively

Use the Study Mode button above to test yourself one card at a time. Try to answer each question before flipping the card. Review cards you find difficult more frequently.

Continue Learning

After mastering Diseases and immunity, explore these related topics: