Human Defence Systems and Protist Disease Recap

A set of practice flashcards covering malaria protist disease basics, phagocytosis, white blood cells, antibodies, memory cells, and related concepts from the notes.

What is the protist that causes malaria?

Plasmodium

What is the vector in malaria?

Mosquito

How can we prevent the spread of malaria?

Use insecticides, vaccinations, remove standing water, and sleep under nets.

Why is malaria not present in Britain?

The notes state: The anopheles mosquito does live in Britain.

Where can microbes enter the body?

Eyes, mouth, skin, ears, nose, cuts, genitals.

What are the body's physical defences and give two examples?

Mucus and hairs in the trachea and nose trap bacteria; acid in the stomach kills bacteria.

What do white blood cells do?

Defend against disease; can consume harmful microbes; can produce antibodies; can produce antitoxins.

What are the two main types of white blood cells?

Phagocytes and lymphocytes.

How do phagocytes detect invaders?

They detect pathogen antigens and move toward the pathogen, then engulf it.

What is the correct order of steps in phagocytosis?

Phagocyte binds to antigen; Engulfs pathogen; Adds digestive enzymes; Pathogen digested; Digested pathogen removed.

In the Mr Waters metaphor, who is the phagocyte and what do the actions represent?

Mr Waters = phagocyte; uniform = antigen; wrap = phagocytosis; arms/legs falling off = digestion.

What do lymphocytes do and what determines antibody specificity?

Produce antibodies; each lymphocyte makes antibodies with a shape complementary to a specific antigen.

Where are lymphocytes produced?

Bone marrow and thymus.

What happens when the correct lymphocyte is found?

It turns into plasma cells and memory cells.

What is the role of plasma cells?

Produce enormous numbers of antibodies.

What is the role of memory cells?

Stay in the blood forever and respond quickly upon reinfection.

What is the relationship between antibodies and antigens in terms of shape?

They are complementary in shape, similar to enzymes and substrates.

Why is HIV infection of lymphocytes problematic?

No lymphocytes means no antibodies and no protection from other infections.

Why are lymphocytes more efficient at destroying pathogens than phagocytes?

Lymphocytes can produce many antibodies; phagocytes can interact with only a few pathogens at a time.

Why does reinfection with the same pathogen produce a faster immune response?

Memory cells stay in the blood and produce antibodies quickly.