Immunity Flashcards
What are antigens
Antigens is any molecule that a triggers an immune response
What is innate immunity?
- consists of the first and second line of defence against foreign invaders
- it is non specific and repels all pathogens equally
Is innate immunity present at birth or acquired later in life?
It is present at birth and is genetically determined
What are the physical barriers involved in the first line of defence of innate immunity?
- Skin
- Mucous membranes
- Cilia
- urine flow
What are the chemical barriers involved in the first line of defence
- urine
- sebum and sweat
- saliva
- tears
What is the purpose of innate immunity?
immediate and non specific protection against pathogens and prevent further entry and reproduction
Does innate immunity have memory of previous infections?
No, innate immunity does not have memory of previous infections and does not produce memory cells
What is fever?
Fever is a temporary increase in body temperature, typically caused by the release of pyrogens in response to an infection
What are pyrogens?
Pyrogens are chemicals released by the body during an infection that can cause an elevation in body temperature.
Which part of the brain is responsible for regulating body temperature?
The hypothalamus, located in the brain,
What is the normal body temperature in humans on average?
37 degrees celcius
What is the purpose of a fever during an infection?
- kill and inhibit the growth of pathogens by creating an unfavourable environment for their survival
- enhance the biochemical and cellular reactions in the body- activity of WBCs
How does fever enhance and accelerate biochemical and cellular reactions?
increased metabolic activity leads to faster chemical reactions and cellular processes
Are temporary or mild fevers a normal response to pathogen invasion?
temporary or mild fevers are a normal response to pathogen invasion and can help the immune system fight off the infection.
When does a high fever occur, and what should it indicate?
A high fever is a sign of significant illness and can sometimes lead to seizures, requiring medical attention.
What is the inflammatory response?
The inflammatory response is a nonspecific chemical reaction that plays a vital role in wound repair and the destruction of pathogens.
What are the effects of chemical signals released during inflammation?
- Causes the capillaries to dilate which increases the blood flow to site of infection
- leads to hot, painful, swollen, red and loss of mobility
What is the role of histamines in the inflammatory response?
- Released by mast cells
- trigger vasodilation- increased blood flow
- increase vascular permeability for phagocytes to move from blood to infected tissue
What is the function of phagocytes?
Specialised white blood cells that engulf and destroy pathogens
Describe the process of phagocytosis.
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What is phagocytosis
- Phagocytosis is the process of engulfing and destroying foreign particles.
Name different types of phagocytes.
- Neutrophils
- monocytes
- macrophages and dendritic cells
What is the role of macrophages in fighting infections?
- Macrophages play a crucial role in fighting chronic infections due to its long life span
What is the role of neutrophils in fighting infections?
- first responders to the site of infection and have a short life span, self destructing within a few days
How do phagocytes migrate from the blood to infected or inflamed tissues?
squeeze between the cells lining the capillaries to migrate from the blood to infected or inflamed tissues.
What is the role of monocytes in the immune response?
- they can differentiate into macrophages and dendritic cells once they reach the site of infection
