Pathogens: Viruses and Bacteria
Our Immune System is one of the major body systems that protects it from disease causing agents, called Pathogens. There are many different kinds of pathogens, but Viruses and Bacteria are the 2 types that causes major illnesses in the human population. There are many differences and similarities between Viruses and Bacteria in their structures, reproduction, the way they cause disease, and treatments.
1st Line of Defense: The Skin 2nd Line of Defense: Inflammation and Fever
Our Immune System has many levels of defense, divided into Non-Specific and Specific Response. The first 2 lines of defenses are considered Non-Specific defenses because the response is the SAME for any infections and it doesn't necessarily recognize what type of infection is causing the sickness.
Our 1st line of defense is the SKIN. The skin is a wall that protects our the inside of our body from anything that comes in, good and bad. The skin doesn't have multiple defenses against the different pathogens that come into the body.
Our 1st line of defense is the SKIN. The skin is a wall that protects our the inside of our body from anything that comes in, good and bad. The skin doesn't have multiple defenses against the different pathogens that come into the body.
Our 2nd line of defense is called the Inflammatory Response (Inflammation) and Fever.
http://www.sumanasinc.com/webcontent/animations/content/inflammatory.html
http://faculty.riohondo.edu/rbethel/videos/micro_inflammation.swf
http://www.sumanasinc.com/webcontent/animations/content/inflammatory.html
http://faculty.riohondo.edu/rbethel/videos/micro_inflammation.swf
As seen above, Inflammatory Response involves several steps:
1) Skin/cells are damaged or punctured.
2) Mast cells release Histamine-histamine causes blood vessels to expand, creating openings for reinforcements to come. As a side effect, histamine causes itchiness.
3) From the openings of blood vessels, phagocytes (eaters of pathogens), clotting factors, and platelets come out (healing)
Fever is triggered to kill pathogen.
1) Skin/cells are damaged or punctured.
2) Mast cells release Histamine-histamine causes blood vessels to expand, creating openings for reinforcements to come. As a side effect, histamine causes itchiness.
3) From the openings of blood vessels, phagocytes (eaters of pathogens), clotting factors, and platelets come out (healing)
Fever is triggered to kill pathogen.
The Immune Response (Specific Defenses/responses)
The body's 3rd line of defense is the strongest and involves multiple events that happen at once. Our body has "memorized" ALL infections since birth until present time. It has "battle plans" for old infections and create "battle plans" for new ones. If the infections is an old one...one that the body has already been exposed to...chances are, you won't even feel the infection because your body has destroyed the pathogens quickly. If the infection is NEW, then your body will need to fight it first, hence, you feel sick and need to be in bed (along with getting over your Fever)
So, what's happening while you're resting in bed? ALOT. And after you get better, you have gained IMMUNITY: ability to fight pathogens without getting sick.
There are 2 ways to gain IMMUNITY:
1) Passive Immunity: Mom's milk, genetics, and vaccinations. All 3 ways does not require you to get sick.
2) Active Immunity: Humoral and Cellular. You will need to get sick and fight the pathogens.
Active Immunity (The Immune Response) involves White Blood Cells (WBC) called Phagocytes, T-lymphocytes (T Cells) and B-lymphocytes (B Cells). T cells are part of the Cellular Immunity and B cells are part of the Humoral Immunity.
Antigens: proteins on the surface of the pathogen that cells use to identify what type of pathogen it is.
Antibodies: Y-shape proteins, produced by B cells, that bind to antigens to deactivate and clump pathogens together.
Phagocytes (Macrophages) engulf (digest) pathogens.
T cells: divide into Helper T cells and Killer T cells and Memory T cells, kill cells that have been infected with Virus by releasing chemicals that puncture holes into the cells, causing cells to lyse (explode)....as a result, the pathogens inside are exposed.
B cells: divide into Plasma B cells and Memory B cells. Plasma B cells produce Antibodies that bind to the Antigen of pathogens, deactivate and clump the pathogens together so that Phagocytes can come and engulf the pathogens.
Memory T and B cells: memorize the information of the pathogen(antigen) that they have encountered and stays behind to patrol the body, ready to fight the next time the same pathogen (antigen) is seen in the body...responding so quickly that you DON'T even feel sick!!.....YOU NOW HAVE IMMUNITY TO THIS PATHOGEN!
Immune Response= http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__the_immune_response.html
Cellular Immunity= http://bcs.whfreeman.com/thelifewire/content/chp18/1802004.html
So, what's happening while you're resting in bed? ALOT. And after you get better, you have gained IMMUNITY: ability to fight pathogens without getting sick.
There are 2 ways to gain IMMUNITY:
1) Passive Immunity: Mom's milk, genetics, and vaccinations. All 3 ways does not require you to get sick.
2) Active Immunity: Humoral and Cellular. You will need to get sick and fight the pathogens.
Active Immunity (The Immune Response) involves White Blood Cells (WBC) called Phagocytes, T-lymphocytes (T Cells) and B-lymphocytes (B Cells). T cells are part of the Cellular Immunity and B cells are part of the Humoral Immunity.
Antigens: proteins on the surface of the pathogen that cells use to identify what type of pathogen it is.
Antibodies: Y-shape proteins, produced by B cells, that bind to antigens to deactivate and clump pathogens together.
Phagocytes (Macrophages) engulf (digest) pathogens.
T cells: divide into Helper T cells and Killer T cells and Memory T cells, kill cells that have been infected with Virus by releasing chemicals that puncture holes into the cells, causing cells to lyse (explode)....as a result, the pathogens inside are exposed.
B cells: divide into Plasma B cells and Memory B cells. Plasma B cells produce Antibodies that bind to the Antigen of pathogens, deactivate and clump the pathogens together so that Phagocytes can come and engulf the pathogens.
Memory T and B cells: memorize the information of the pathogen(antigen) that they have encountered and stays behind to patrol the body, ready to fight the next time the same pathogen (antigen) is seen in the body...responding so quickly that you DON'T even feel sick!!.....YOU NOW HAVE IMMUNITY TO THIS PATHOGEN!
Immune Response= http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__the_immune_response.html
Cellular Immunity= http://bcs.whfreeman.com/thelifewire/content/chp18/1802004.html
Vaccinations and Antibiotics
Vaccines are administered before a person is infected with the pathogen so that they are prevented from getting sick from the pathogen.
There are several ways to make vaccines: the most common are vaccines that contain the ANTIGEN of a pathogen. Once injected, it triggers an Immune Response from our body. HOWEVER, since it is only Antigens and not the actual pathogen, we don't actually get sick. The result is that our body is now informed of the pathogen and ready to fight quickly, if it ever encounters the pathogen that was in the Vaccine. YOU NOW HAVE IMMUNITY to this pathogen!!
http://highered.mcgraw-hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120078/bio39.swf::Constructing%20Vaccines
Making Vaccines!! http://www.pbs.org/wgbh/nova/bioterror/vacc_flash.html (NEED FLASH)
http://www.pbs.org/wgbh/nova/bioterror/vacc_nf.html (NON FLASH)
Vaccination and opportunistic infections POWERPOINT notes
**Side note: Just think of Vaccinations as a castle given a PICTURE of what the enemy looks like and their weaknesses. The castle and soldiers are now able to identify the enemy quicker and fight them faster. As a result, when the REAL enemy invades, they are destroyed before they can cause damage **
Antibiotics in our medicines work to inhibit (stop) the formation of cell walls. Since bacteria and fungi have cell walls and Viruses DO NOT, antibiotics are ONLY affective against bacteria and NOT viruses.
So, when you visit your doctor with a cold, why does he give you antibiotics? Colds are caused by Viruses. So why? The answer is he is giving you antibiotics to take care of the bacterial infections so that your body can focus on just the viral infections.
There are several ways to make vaccines: the most common are vaccines that contain the ANTIGEN of a pathogen. Once injected, it triggers an Immune Response from our body. HOWEVER, since it is only Antigens and not the actual pathogen, we don't actually get sick. The result is that our body is now informed of the pathogen and ready to fight quickly, if it ever encounters the pathogen that was in the Vaccine. YOU NOW HAVE IMMUNITY to this pathogen!!
http://highered.mcgraw-hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120078/bio39.swf::Constructing%20Vaccines
Making Vaccines!! http://www.pbs.org/wgbh/nova/bioterror/vacc_flash.html (NEED FLASH)
http://www.pbs.org/wgbh/nova/bioterror/vacc_nf.html (NON FLASH)
Vaccination and opportunistic infections POWERPOINT notes
**Side note: Just think of Vaccinations as a castle given a PICTURE of what the enemy looks like and their weaknesses. The castle and soldiers are now able to identify the enemy quicker and fight them faster. As a result, when the REAL enemy invades, they are destroyed before they can cause damage **
Antibiotics in our medicines work to inhibit (stop) the formation of cell walls. Since bacteria and fungi have cell walls and Viruses DO NOT, antibiotics are ONLY affective against bacteria and NOT viruses.
So, when you visit your doctor with a cold, why does he give you antibiotics? Colds are caused by Viruses. So why? The answer is he is giving you antibiotics to take care of the bacterial infections so that your body can focus on just the viral infections.
HIV and Opportunistic Infections
Human Immunodeficiency Virus (HIV) is a virus that is specialized in attacking our strongest WBC, the T-Cells. Because the T-cells are attacked and destroyed by HIV, it makes the rest of our Immune System much more vulnerable to any infections. THUS, people who have HIV are dying from ALL OF THE INFECTIONS that are attacking the body.
We call these infections Opportunistic Infections, because they usually don't cause death, but a weaken Immune System (or a compromised Immune System) enables them to do so. An example of infections that are weak but can kill HIV patients are the common cold.
And so, when someone has AIDS (caused by HIV) you can expect to see that the higher the # of HIV, the lower the # of T cells.
We call these infections Opportunistic Infections, because they usually don't cause death, but a weaken Immune System (or a compromised Immune System) enables them to do so. An example of infections that are weak but can kill HIV patients are the common cold.
And so, when someone has AIDS (caused by HIV) you can expect to see that the higher the # of HIV, the lower the # of T cells.
There are several ways that HIV can be transmitted:
1) mixing infected blood with a bodily fluid
2) sexual intercourse
3) mothers to child
4) and needles
You CANNOT get HIV from sitting on toilet seats, eat food cooked by someone who has HIV.....
In reality, you need to acquire a large amount of HIV in a fluid to actually be affected by HIV. Once HIV is exposed to the air, they die.
1) mixing infected blood with a bodily fluid
2) sexual intercourse
3) mothers to child
4) and needles
You CANNOT get HIV from sitting on toilet seats, eat food cooked by someone who has HIV.....
In reality, you need to acquire a large amount of HIV in a fluid to actually be affected by HIV. Once HIV is exposed to the air, they die.