Infectious and Non-Infectious Disease
What is the key difference between infectious and non-infectious diseases?
Infectious diseases are caused by pathogens and can be spread; non-infectious diseases are not caused by pathogens and cannot be spread.
Which pathogen consists only of misfolded proteins?
Prions
What is the main role of the first line of defence?
Prevent pathogens from entering the body
What type of immunity is the second line of defence?
Non-specific and innate
What are the two main features that distinguishes the third line of defence from the first two?
Specificity and memory
True or False: cancers are classified as infectious diseases
False
Which pathogen is non-cellular and requires a host cell to reproduce?
Virus
Name one physical and one chemical barrier in the first line of defence
Skin, stomach acid
Which two types of white blood cells are involved in phagocytosis?
Neutrophils and macrophages
Which cells produce antibodies in the humoral response?
B-cells
Name an example of an infectious and a non-infectious disease
Various
What is typically used to treat bacterial infections?
Antibiotics
Why is intact skin considered one of the most effective barriers to infection
It forms a physical barrier that prevents pathogen entry
What is the main purpose of the inflammatory response?
To isolate and eliminate pathogens and begin tissue repair
What is the role of helper T cells in the immune response
Activate B-cells and cytotoxic T-cells
Why are lifestyle diseases like cardiovascular disease considered non-infectious?
They are caused by factors such as diet, exercise, and genetics, not pathogens
Which pathogens are multicellular organisms that live in or on a host and feed off it?
Parasite
How do mucous membranes protect against pathogens
They trap pathogens and can contain enzymes or acids that destroy them
How do prostaglandins and vasodilation assist in the inflammatory response?
They increase blood flow and permeability, allowing immune cells to reach the infection site.
What is the difference between the humoral and cell-mediated responses?
Humoral targets pathogens in body fluids; cell-mediated targets infected body cells.
True or False: All contagious diseases are infectious, but not all infectious diseases are contagious
True
Which pathogen is typically a unicellular eukaryotic organism?
Protist
How tears and saliva help prevent infection
They contain enzymes like lysozyme that break down bacterial cell walls.
Describe the role of natural killer (NK) cells in the second line of defence.
They identify and destroy virus-infected or abnormal cells by inducing apoptosis
How do memory cells provide long-term immunity?
They remain in the body after an infection and quickly respond if the same pathogen invades again