Chapter 35 Immune System and Disease

Goal: To understand how the body fights against pathogens that try to cause disease

35.1 Infectious Disease

Causes of Infectious Disease

Pasteur and Koch made observations that led them to the conclusion that disease was caused by __________________. This was known as the “_______ _______ _____ disease”.

Disease causing organisms include ___________, ____________, _____________, _______________ and parasites.

Koch’s postulates played a vital role in the development of modern medicine. Koch used these rule to help identify the ________________ that cause __________________.

List Koch’s Postulates

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Not all microorganisms are harmful; many are either____________ or ___________________.

Pathogenic microorganisms will destroy cells, release _________________ or block the flow of ______________ to organs.

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How is Disease Spread?

Coughing and sneezing release thousands of droplets of water that can be ______________ or ____________ on surfaces.

_______________ contact occurs when a person touches objects that may have the pathogen on the surface. When the person brings their hand to their _______________ or eyes the pathogen is transferred and _______________ the body.

Hand washing and covering your mouth when coughing and sneezing ______________ the spread of these pathogens.

Some pathogens, like sexually transmitted diseases, need the exchange of _____________ fluids from host to host. Others pathogens can be transmitted through blood from _____________syringes. Preventing the spread of theses pathogens is simple, abstaining from sexual activity, practicing __________ sex and avoiding _______________ drugs.

Many pathogens can be spread by drinking _________ or fruit and ______________. When infected persons excrete in a water supply they can______________ the pathogen to people who may drink the water. Watering fruits and vegetables with contaminated water spreads the ______________ to those who may consume the fruits and vegetables

__________________ refers to the spread of disease from animals to humans. The spread of these diseases occurs when humans___________ the infected animal, get _________________ or live in close proximity to infected animals. Organisms that carry the zoonotic diseases are called ______________.

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35.2 Defenses against Infection

Nonspecific Defenses

The first line of defense includes your _________, __________, __________ and ___________. The ____________ provides a barrier to prevent infection, while tears, mucus and saliva contain______________, an enzyme, which breaks down bacterial cell walls.

The second line of defense occurs when the pathogen enters the body. __________________ ______________ occurs because the pathogen stimulates cells called mast cells to release ______________________. _________________ cause an increase of blood flow to the area and this brings ____________ blood cells that engulf bacteria, increase_______________, swelling and _____________.

________________ produce proteins that inhibit the synthesis of viral proteins and allow time for the ______________ immune defenses to respond.

A _____________is caused by chemicals released in the body. Increased body temperature__________ the growth of pathogens and _________________ up the activity of the immune response.

Specific Defenses: The Immune System

The immune system recognizes all the body’s cells and proteins as “_________”. Chemical markers act as _______________ so the immune system will not attack.

Cells that are recognized as “____________” or “_______________” have molecules called _____________ that are on the outer surfaces.

The immune system will respond to antigens by ______________ the number of attackers or producing ________________. Antibodies are ____________ that tag antigens for destruction by the ___________________ system.

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The ability to recognize specific pathogens, respond and have a memory for the pathogen is called an ________________ ________________.

The main cells of the immune system are the B ______________ (B cells) and T ________________ (T cells). B cells are produced in the ___________ ___________ and mature in the ___________ ______________ while T cells are produced in the _____________ ____________ and mature in the _____________ _______________. T cells and B cells fight antigens in the lymph nodes and _________________.

B cells, with their embedded _________________, will encounter antigens in body fluids while T cells must be presented with an antigen by an _____________ cell or ______________ cells.

Draw Figure 35-6 and Figure 35-7

The Immune System in Action

Humoral Immunity

Humoral immune response is activated when _________ embedded on B cells __________ to antigens.

B cells have Y shaped _______________ that bind to specific antigens. When the antigen binds to the B cell, T cells stimulate ______________ production of two types of B cells; _____________ cells and _________________ cells.

_______________ cells produce and release antibodies into the blood stream. They attach to the surface of the antigen and signal

it for _______________ or disable the antigen.

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The human body can produce over __________________ different antibodies.

After the infection plasma cells __________ but memory B cells remain ________________ and can react quickly to the same pathogen if it enters the body again. ________________ cells can quickly produce plasma cells in a secondary response to a pathogen and provide long term ________________ from to certain diseases.

Make flow chart, of your own, that will help you understand the Humoral Immune Response

Cell – Mediated Immunity

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When a cell is infected with a pathogen or when a _____________________ consumes a pathogen, the cell will display a portion of the antigen on the ______________ of its membrane. This causes ___________________ to become activated and they in turn activate more Helper T cells which will activate more ________________, _____________ T cells and produce _______________ T cells.

_______________________ hunt and kill infected body cells by rupturing the cell membrane or initiating ______________ (programmed cell death).

_________________________ remain to protect against any future infections

_______________________ cells work at inhibiting the immune response once the infection is under control.

Organ donors must have surface markers that are a ____________ match to the recipient so the recipient’s _________________cells don’t attack and destroy the transplanted organ. Recipient still will have to take _______________ that will supress the ________ _____________ immune response.

Make flow chart, of your own, that will help you understand the Cell – Mediated Immune Response.

35. 3 Fighting Infectious Disease

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Acquired Immunity

200 years ago Edward Jenner developed the first________________ by injecting fluid from cowpox into young boy names James Phipps. James was then exposed to small pox and did not acquire the disease. Since then injections of weakened or dead pathogens which then cause an immune response are known as ____________________.

Vaccines or natural exposure to pathogens that cause an immune response (production of B cells and Tells) is known as ________________ __________________.

_________________ ________________ is when antibodies are passed on to another individual through things like breast milk or through the ______________ from mother to fetus. Other types of _______________ _____________ can be when antibodies are injected into the body of an infected person. _____________ ________________ is short lived since the foreign antibodies are destroyed.

Public Health and Medications

Public health initiatives have prevented disease by monitoring __________ and _____________ supplies, promoting _________________ and promoting behaviors that prevent infections.

Medications like ______________ and __________________ drugs have been used to fight pathogens.

New and Re – Emerging Disease

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Recently new emerging diseases have appeared (SARS, AIDS, Hantavirus, etc.) due to humans moving into new areas and being exposed to different_______________ and different__________________. Another reason is the increased trade of _____________ ______________ which gives ______________ new opportunities to jump from animal to host.

The ___________ ____ __________ has allowed for the evolution of drug resistant strains of pathogens along with the failure of some individuals to be ___________________.

35.4 Immune System Disorders

When the Immune System Overreacts

Allergies occur when _________________ enter the body and cause __________ cells to release ________________ causing an ____________________ response, increased mucus, watery eyes, runny nose and sneezing.

Allergic reactions in the respiratory system can cause _________________. Asthma causes the ________________ of air passages making breathing difficult. Asthma can be triggered by a number of things.

__________________ diseases occur when the immune system fails to identify the body’s cells as “__________” and proceeds to ____________ certain cells.

HIV and AIDS

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What are two reasons for HIV being so deadly?

When are HIV – infected people diagnosed with having AIDS?

What are the four ways HIV are transmitted?

Why would having sex with an intravenous drug user increase your risk of acquiring HIV?

Why haven’t scientists and doctors been able to make a vaccine for HIV?

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