Defence against disease Flashcards
What is a pathogen?
A pathogen is a disease-causing organism that can infect humans and other organisms.
What are the main types of pathogens?
The main types of pathogens are viruses, bacteria, fungi, and protists.
Are archaea known to cause diseases in humans?
No, archaea are not known to cause any diseases in humans.
What are some examples of bacterial pathogens?
Examples include Streptococcus pneumoniae, Staphylococcus aureus, Escherichia coli (E. coli), and Klebsiella pneumoniae.
What types of diseases can viruses cause?
Viruses can cause a wide range of diseases, from the common cold to AIDs.
What are some examples of diseases caused by fungi?
Fungi can cause skin diseases like ringworm and athlete’s foot, as well as infections in the lungs or nervous system.
What is an example of a disease caused by a protist?
Malaria is caused by a protist parasite called Plasmodium.
What was the significance of Ignaz Semmelweis’s observations in Vienna during the 1840s?
Semmelweis observed higher mortality rates in maternity wards attended by medical students compared to midwives, leading to the introduction of hand washing with chlorinated lime solution, which dramatically reduced mortality rates.
What important discovery did John Snow make during the 1854 cholera epidemic in London?
John Snow mapped cholera cases in London, identifying a contaminated water pump as the source, which led to the understanding of cholera as a waterborne disease and improvements in urban sanitation.
How did the observations of Semmelweis and Snow contribute to the field of infectious diseases?
These observations were crucial in developing germ theory and improving public health measures to control infectious diseases.
What is the primary function of the skin as a barrier?
The skin acts as both a physical and chemical barrier to protect against pathogens.
How does the skin serve as a physical barrier?
The skin provides a continuous, impassable barrier that prevents the entry of potentially infectious pathogens.
What role does desquamation play in skin defense?
Desquamation, or the shedding of dead skin cells, helps dislodge pathogens that may have adhered to the skin surface.
How does the skin’s acidity contribute to pathogen defense?
The skin’s acidity creates an unfavorable environment for many pathogens, helping to kill or inactivate them.
What is the role of beneficial microorganisms on the skin?
Beneficial microorganisms compete with invading pathogens, preventing their colonization and reducing the risk of infection.
What are antimicrobial peptides (AMPs)?
AMPs are small peptides secreted by skin cells that have antibiotic-like properties, directly killing pathogens and enhancing immune responses.
How do keratinocytes contribute to skin immunity?
Keratinocytes act as active immune cells that release inflammatory cytokines and antimicrobial molecules in response to pathogens.
What is the function of mucous membranes in pathogen defense?
Mucous membranes line body cavities and secrete mucus, which traps pathogens and facilitates their removal from the body.
How do tears contribute to eye health?
Tears contain enzymes that act as chemical barriers, helping to wash away pathogens and prevent infections in the eyes.
What happens when the skin barrier is breached?
When the skin barrier is compromised, it allows pathogens to enter, leading to potential infections; this activates the innate immune system for protection.
What is the primary purpose of blood clotting?
The primary purpose of blood clotting is to seal cuts in the skin, preventing blood loss and pathogen entry.
What initiates the blood clotting process?
The process is initiated when platelets adhere to the site of a cut or injury.
What do platelets release during the clotting process?
Platelets release clotting factors that trigger a cascade of reactions leading to blood clot formation.
What is the coagulation cascade?
The coagulation cascade is a series of complex biochemical reactions that lead to the formation of a blood clot.