SC.912.L.14.52_Explain the basic functions of the human immune system, including specific and nonspecific immune response, vaccines, and antibiotics. (AA)
SC.912.L.14.6 Explain the significance of genetic factors, environmental factors, and pathogenic agents to health from the perspectives of both individual and public health. |
What I Need to Know:
|
What are diseases?SC.912.L.14.6
Explain the significance of genetic factors, environmental factors, and pathogenic agents to health from the perspectives of both individual and public health. |
|
Nonspecific Defense
(Innate Response)
First Line of Defense:
- Mechanical: Skin and mucous membranes
- Chemical: Tears containing lysosomes that digest pathogens, low pH of the gastric juice, vagina.
- Reflexes: Sneezing and coughing
Second Line of Defense:
- Inflammatory Response
- Fever: Increased body temperature helps slow down the growth of bacteria, helps destroy infected body cells and stimulates the
- Macrophages: Phagocytosis of pathogens
- Natural killer cells (NK): Destroy infected cells
- Complement Proteins: complement the job of macrophages by immobilizing the pathogens
- Interferon: interfere with the synthesis of viruses and combat bacterial and parasitic infections by:
- activating the most cells within a few hours after pathogen infection
- inhibiting cell division
- stimulating NK cells to kill virus-infected cells
Both the 1st and 2nd Lines of Defense make up the Nonspecific Immunity
The nonspecific or innate response DO NOT target specific pathogens, but it provides broad protection against all kinds of threats.
Specific/ Acquired Immune Response
(3rd Line of Defense)
Specific Defense
Third Line of Defense:
- Pathogens who were able to survive the 1st and 2nd lines of defense, will face the specific 3rd line of defense, AKA immune response.
- Lymphocytes (B-cells and T- cells)
- Antibodies
- This is an acquired immune response. Can be acquired actively (when you make you own antibodies when you get sick of get vaccinated); or can be acquired passively (when you do nothing to get the antibodies, which are generally obtained via placenta, of the mother's breast milk)
EOC SAMPLE QUESTION:
The immune system has both specific and nonspecific defenses against viral infections. Which statement describes a nonspecific response of the immune system in fighting viral infections?
A. T cells are produced to search out and destroy the viruses.
B. Memory B cells are activated to rapidly respond to the viral infection.
C. Plasma cells quickly replicate and release antibodies that bind to the viruses.
D. Virus-infected cells produce interferons that lead to the inhibition of viral replication.
The immune system has both specific and nonspecific defenses against viral infections. Which statement describes a nonspecific response of the immune system in fighting viral infections?
A. T cells are produced to search out and destroy the viruses.
B. Memory B cells are activated to rapidly respond to the viral infection.
C. Plasma cells quickly replicate and release antibodies that bind to the viruses.
D. Virus-infected cells produce interferons that lead to the inhibition of viral replication.
Immunity
Passive Immunity: Immunity acquired from the transfer of antibodies that were produced by another person.
Active Immunity: Naturally acquired active immunity occurs when the person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response.
Artificially acquired active immunity can be induced by a vaccine, a substance that contains the antigen.
- Protection from passive immunity decreases in a short time, usually within weeks or months.
- For example, antibodies passed from the mother to the baby before birth through the placenta, or after birth through milk confer passive immunity to the baby for the first 4-6 months of life.
Active Immunity: Naturally acquired active immunity occurs when the person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response.
Artificially acquired active immunity can be induced by a vaccine, a substance that contains the antigen.
Blood Type Immunity
There are four main blood types: A, AB, B and O. AB positive is considered the universal recipient, and O negative is considered the universal donor.
- Anti-A and anti-B antibodies are pre-formed; they are present in plasma even if individual has never been exposed to those antigens
- Pathogen: A disease-causing agent (viruses, bacteria, protists, fungi). Pathogens work by: destroying cells, releasing chemical toxins that interfere with proper cell function. Parasitic worms can take up host nutrients and/or block blood flow.
- Symbiont: Harmless or beneficial organisms containing nutrients, growing, and reproducing inside the host without causing disease.
- Zoonosis: a disease that can be transmitted from animals to humans.
- Vectors: Animals carriers of diseases that are part of zoonosis, usually not getting sick in the process. (bats, mosquitoes)
- Nonspecific Defense: Is a combination of physical and chemical barriers in the first and second lines of defense system of the body's fight against a wide range of pathogens (not a specific group only).
- Inflammatory Response: Part of the nonspecific, second line of defense in which the infected area gets red, swollen or inflamed, hot, and painful.
- Histamine: Chemical released by mast cells during the inflammatory response that causes vasodilation, and increased blood flow into the affected area.
- Vaccine: is a preparation containing weakened fragments of a pathogen, or a dead pathogens that won't cause disease. Vaccines work by provoking an immune response and the formation of antibodies and memory B-Cells, which in the event of an actual infection will work quickly identifying and marking for destruction the pathogen.
- Antibiotics: are drugs that work only in bacteria, generally by destroying their cell walls, or preventing the formations of a cell wall. Antibiotics DO NOT work on viruses! The indiscriminate use of antibiotics is the leading cause of antibiotic resistant bacteria.
- Antibodies: a Y-shaped protein found in the body's humors (lymph, blood) produced in response to and counteracting a specific antigen. Antibodies combine chemically with such antigens that the body recognizes as alien, such as bacteria, viruses, and foreign substances in the blood.
- Antigens: a toxin or other foreign substance that induces an immune response in the body, especially the production of specific antibodies
- Memory Cells: A cell in the immune system that, when exposed to an invading pathogen, replicates itself and remains in the lymph nodes searching for the same antigen, resulting in a more efficient and rapid response to any subsequent attack. Note: The creation of memory cells is one of the main goals of vaccination.
- Passive Immunity: Immunity acquired from the transfer of antibodies that were produced by another person. Protection from passive immunity decreases in a short time, usually within weeks or months. For example, antibodies passed from the mother to the baby before birth through the placenta, or after birth through milk confer passive immunity to the baby for the first 4-6 months of life.
- Active Immunity: Naturally acquired active immunity occurs when the person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response. Artificially acquired active immunity can be induced by a vaccine, a substance that contains the antigen.
STANDARD PRACTICE
1. The hypothesis that germs cause disease is called germ theory. Before the 1880s, many
scientists believed in the idea of spontaneous generation—the sudden appearance of living organisms from nonliving matter. Today germ theory is accepted as one of the great discoveries of medicine. Which of the following is a way in which germ theory has had an impact on modern health care?
A. the development of safer anesthetics
B. the development of genetic medicine
C. the development of vaccines against childhood diseases
D. the rise in public awareness about the causes of heart disease
2.
2.The human immune system can produce a specific response or a nonspecific response to infection. Which of the following is a specific immune response of the human immune system?
F. fever
G. inflammation
H. antigen display
I. interferon release
3
3. When a pathogen infects a host cell, the body produces specialized white blood cells
that detect and destroy the specific pathogen. Pathogens have unique proteins on their
surfaces called antigens. The specificity of the immune system is due to the antigen receptors on immune cells. These antigen receptors bind to antigens that match their shape exactly. Helper T cells are regulatory white blood cells with specific antigen receptors on their surfaces. Activated helper T cells do not directly attack infected
body cells or pathogens. Instead, they grow and divide, producing more helper T cells with identical receptors on their surfaces. The helper T cells activate the destruction of the infected cells and the removal of extracellular pathogens from the body. How does the presence of more helper T cells affect the immune response to a specific pathogen?
A. the more helper T cells, the more antibodies are produced
B. the more helper T cells, the less the body is able to react to a specific pathogen
C. the more helper T cells that are activated, the more robust the immune response
D. the more helper T cells, the more infected body cells will be attacked and destroyed
1. The hypothesis that germs cause disease is called germ theory. Before the 1880s, many
scientists believed in the idea of spontaneous generation—the sudden appearance of living organisms from nonliving matter. Today germ theory is accepted as one of the great discoveries of medicine. Which of the following is a way in which germ theory has had an impact on modern health care?
A. the development of safer anesthetics
B. the development of genetic medicine
C. the development of vaccines against childhood diseases
D. the rise in public awareness about the causes of heart disease
2.
2.The human immune system can produce a specific response or a nonspecific response to infection. Which of the following is a specific immune response of the human immune system?
F. fever
G. inflammation
H. antigen display
I. interferon release
3
3. When a pathogen infects a host cell, the body produces specialized white blood cells
that detect and destroy the specific pathogen. Pathogens have unique proteins on their
surfaces called antigens. The specificity of the immune system is due to the antigen receptors on immune cells. These antigen receptors bind to antigens that match their shape exactly. Helper T cells are regulatory white blood cells with specific antigen receptors on their surfaces. Activated helper T cells do not directly attack infected
body cells or pathogens. Instead, they grow and divide, producing more helper T cells with identical receptors on their surfaces. The helper T cells activate the destruction of the infected cells and the removal of extracellular pathogens from the body. How does the presence of more helper T cells affect the immune response to a specific pathogen?
A. the more helper T cells, the more antibodies are produced
B. the more helper T cells, the less the body is able to react to a specific pathogen
C. the more helper T cells that are activated, the more robust the immune response
D. the more helper T cells, the more infected body cells will be attacked and destroyed
4. Louis Pasteur, a French microbiologist, developed a vaccine against rabies. In 1885, he tested it on a young man infected with the microbe that causes rabies. Medical researchers searching for a vaccine against the virus that causes AIDS say that a vaccine against this disease faces years of testing. Why can’t doctors try out untested vaccines on people today as Pasteur did in the 1880s?
F. Drug companies delay releasing vaccines because they need to maximize profits.
G. There is much more unnecessary government red tape today than there was in the 1880s.
H. Vaccines developed today are not as effective as those that were developed in the 1800s.
I. Ethical issues and laws prevent doctors from giving people vaccines that may contain unknown hazards.
5. In the immune system’s specific response, white blood cells can target specific types of disease-causing microbes. How do white blood cells recognize invading microbes?
A. Receptor proteins on their surfaces bind to specific antigens.
B. Helper T cells release antibodies that bind with the antigens.
C. Natural killer cells puncture and destroy the infected body cells.
D. Plasma cells bind to the viral antigens and mark them for destruction.
6.Two types of white blood cells are macrophages and natural killer cells. How are the roles of a macrophage and a natural killer cell different?
F. Macrophages target specific cells, while natural killer cells kill all pathogens.
G. Macrophages ingest pathogens and dead cells, while natural killer cells only target cancer cells.
H. Macrophages attack lymph cells, and natural killer cells clean up debris from dead cells.
I. Macrophages ingest and kill pathogens, while natural killer cells puncture the cell membranes of infected cells.
F. Drug companies delay releasing vaccines because they need to maximize profits.
G. There is much more unnecessary government red tape today than there was in the 1880s.
H. Vaccines developed today are not as effective as those that were developed in the 1800s.
I. Ethical issues and laws prevent doctors from giving people vaccines that may contain unknown hazards.
5. In the immune system’s specific response, white blood cells can target specific types of disease-causing microbes. How do white blood cells recognize invading microbes?
A. Receptor proteins on their surfaces bind to specific antigens.
B. Helper T cells release antibodies that bind with the antigens.
C. Natural killer cells puncture and destroy the infected body cells.
D. Plasma cells bind to the viral antigens and mark them for destruction.
6.Two types of white blood cells are macrophages and natural killer cells. How are the roles of a macrophage and a natural killer cell different?
F. Macrophages target specific cells, while natural killer cells kill all pathogens.
G. Macrophages ingest pathogens and dead cells, while natural killer cells only target cancer cells.
H. Macrophages attack lymph cells, and natural killer cells clean up debris from dead cells.
I. Macrophages ingest and kill pathogens, while natural killer cells puncture the cell membranes of infected cells.