The three lines of defense your body has against disease include all
of the following except:
A) Mechanical Barriers (e.g. skin and mucous membranes)
B) Chemical Barriers (e.g. stomach acid and enzymes)
C) Cellular Defenses (e.g. white blood cells)
D) Antibacterial Soap
The correct answer is D) Antibacterial Soap. Antibacterial soap is not part of the body's natural defense mechanisms against disease. It is a man-made product designed to kill bacteria and is not part of the body's immune system.
The three lines of defense your body has against disease are:
1. First Line of Defense: Innate Immunity
This is the body's initial protection against pathogens (disease-causing agents) and is always active. It includes physical barriers like the skin, mucous membranes, and certain chemicals in body fluids (e.g., tears, saliva, stomach acid) that help prevent pathogens from entering the body or inhibit their growth.
2. Second Line of Defense: Inflammatory Response
If pathogens manage to penetrate the first line of defense, the body triggers an inflammatory response to limit their spread. This involves processes like increased blood flow, release of chemical signals (like histamine), and activation of immune cells (like phagocytes) that attack and destroy the pathogens.
3. Third Line of Defense: Adaptive Immunity
If a pathogen successfully evades the first two lines of defense, the body mounts an adaptive immune response. This response is specific to the particular pathogen encountered and provides long-lasting protection. It involves specialized immune cells (like T and B lymphocytes) that recognize and destroy the pathogen, as well as memory cells that "remember" the pathogen for future encounters, leading to a faster and stronger response.
To summarize, the first line of defense is the body's physical and chemical barriers, the second line is the inflammatory response, and the third line is the adaptive immune response. These lines of defense work together to protect the body from disease.
The three lines of defense your body has against disease include:
1. First line of defense: This is the body's external barrier that helps prevent pathogens (harmful microorganisms) from entering the body. It includes physical barriers such as the skin, which acts as a protective barrier against germs, and the mucous membranes, which line the respiratory and digestive tracts and trap pathogens.
2. Second line of defense: If pathogens manage to penetrate the first line of defense, the body activates the second line of defense, which consists of non-specific defenses. This includes inflammation, which is a response to injury or infection that helps fight off pathogens, as well as the release of certain chemicals called cytokines that attract immune cells to the site of infection. Other components of the second line of defense include natural killer cells, phagocytes (such as macrophages and neutrophils), and the complement system, which is a group of proteins that help destroy pathogens.
3. Third line of defense: If pathogens successfully evade the first and second lines of defense, the body activates the third line of defense, also known as the immune response. This is a highly specific defense system that involves the immune cells, including lymphocytes (B-cells and T-cells), which are responsible for recognizing and attacking specific pathogens. The immune response also involves the production of antibodies, which are specialized proteins that help neutralize and eliminate specific pathogens. This line of defense is responsible for creating long-term immunity to specific diseases.