Homeostasis
What is homeostasis?
Homestasis is the process by which a living organism maintains a stab;e internal environment despite changes in external conditions.
Name a common viral infection.
Influenza, Covid-19
Name a physical barrier.
Skin, mucus, saliva, cillia.
What are the two responses in the 3rd line of defence?
The humoural response and the cell-mediated response.
What are the two types of disease transmission?
Direct and Indirect contact.
Give an example of negative feedback.
An example of negative feedback is the regulation of body temperature, where the body responds to overheating by sweating to cool down.
What is an infectious diesase?
A disease caused by pathogens such as bacteria, viruses, or parasites.
What are phagocytes?
Phagocytes are white blood cells that engulf and digest pathogens and debris in a process known as phagocytosis.
What are antibodies?
Antibodies are proteins produced by B-cells that specifically bind to antigens on pathogens, marking them for destruction.
Name one example of direct contact and one example of indirect contact.
Direct: Physical touch, droplet (coughing or sneezing near someone)
Indirect: Airborne, contaminated food/water, contamined objects, disease specific vector.
What part of the brain regulates temperature?
The hypothalamus.
What is the main structural difference between a virus and a bacterium?
Bacteria are living cells with a complex cellular structure, while viruses are non-living entities with a much simpler structure, essentially genetic material encased in a protein shell
Explain the role of a fever.
Fever is an increase in body temperature that enhances immune function and inhibits pathogen growth.
Explain the role of memory cells. Name both types and which response each are present in.
Memory cells are long-lived immune cells that remember a specific antigen and respond more effectively upon re-exposure. There are Memory T-cells for thecell-mediated response and MemoryB-cells for the humoural response.
Name a factor affecting disease transmission and explain it.
Pathogen persistance
Tramission mechanism
Population immunity
Mobility of Population
Describe osmoregulation.
Osmoregulation is the process by which organisms regulate the water and electrolyte balance in their bodies, crucial for maintaining homeostasis.
What is antibiotic resistance?
Occurs when microorganisms (like bacteria) change/evolve in ways that make antimicrobials, including antibiotics, less effective at fighting infections.
Explain the role of cilia in the first line of defence.
Cilia, tiny hair-like structures lining the respiratory tract, act as a first line of defense against pathogens by trapping and moving mucus and debris away from the lungs.
Is the third line of defence specific or non-specific? Discuss what this means.
The 3rd line is specific. This means that it responds to each pathogen it encounters in a specific way.
Explain herd immunity and what factor of disease transmission it relates to.
Herd immunity occurs when a significant portion of a population becomes immune to an infectious disease, limiting further disease spread. This is due to the lack of available hosts to contaminate. It relates to the population immunity factor of disease transmission.
What is thermoregulation?
Thermoregulation is the process by which an organism maintains its body temperature within certain boundaries, even when the surrounding temperature is different.
What is the role of antibiotics?
Antibiotics are medications used to treat bacterial infections by killing bacteria or inhibiting their growth, but they are ineffective against viral infections.
What are natural killer cells?
Natural killer cells are a type of lymphocyte (white blood cells) in the innate immune system that destroy infected and diseased cells.
What is the lock and key system in the third line of defence referring to and explain what this means.
The lock and key system in the 3rd line of defence is referring to the antigens and antibodies. It means that each antibody responds only to one specific antigen.
Discuss what Quarantine is as a method of controlling disease and realte it to at least one factor affecting disease.
Quarantine is a method of controlling diesease in which infected individuals are kept seperate from healthy individuals. This can relate to the mobility of the population, as infected individauls are prevented from being mobile within or between populations.