Human BiologyImmune System

Ch. 31

True or False

1. B cells and T cells mature in thymus.

2. Cell-mediated immune response deals with B cells.

3. Lymphocytes are concentrated in lymph nodes.

4. HIV weakens the immune system by killing cytotoxic T cells.

5. T cells produce antibodies against foreign antigens.

6. Spleen is located behind the stomach and filters pathogens in the blood.

7. Without helper T cells, the specific immune system will not be activated.

Objectives

10. Organisms have a variety of mechanisms to combat disease.As a basis for understanding the human immune response, students know:

a. the role of the skin in providing nonspecific defenses against infection.

b. the role of antibodies in the body's response to infection.

c. how vaccination protects an individual from infectious diseases.

d. there are important differences between bacteria and viruses, with respect to their requirements for growth and replication, the primary defense of the body against them, and effective treatment of infections they cause.

e. why an individual with a compromised immune system (for example, a person with AIDS) may be unable to fight off and survive infections of microorganisms that are usually benign.

f.* the roles of phagocytes, B-lymphocytes, and T-lymphocytes in the immune system.

Immune System Function

Recognize pathogens and keep them out or kill them.

__________ = disease-causing agent

Ex. _________________________

Pathogen has to _____ body to cause disease.

Standard

10a. Students know the role of the skin in providing nonspecific defenses against infection

10f.* the roles of phagocytes, B-lymphocytes, and T-lymphocytes in the immune system.

Innate vs. Acquired Immunity Innate Immunity

-Natural, “_____________”

-1st line of defense

(_____, ______, _____ _______, _______, phagocytes)

- Leads to an ___________ response.

Acquired Immunity

-Developed, “______”

-2nd line of defense.

(____________, lymphocytes such as ______, ______)

-destroy & remember

Skin

A ________ __________ that prevents _________ from entering/invading the body.

Inflammatory Response (Non-specific)- Caused by an Injury

(______________)

_________ is released capillaries ________ (red,

swollen) WBC, platelets move to

wounded area ______ kill pathogens

(phagocytosis) & ________ seal wound

dead tissues form ________

Phagocytes (non-specific immunity)

They engulf & “____” or _______ all invaders they encounter.

Ex. ______________________________

Interferon Produces proteins that protect your cells from virus.

Lymphocytes (Specific Immunity)

T-cells- Develop in _________3 types- _______= kill

pathogens- _______ = activates B

& T cells- __________ =

regulates B, T cells

B-cells- Develop in ______ _______2 types- ____________ = remember

the pathogens- ____________ = produce

antibodies

All blood cells (RBC and WBC) come from _______ _________.

Standard

10b. Students know the role of antibodies in the body's response to infection.

Antigen and Antibody (B cells)

Antigen - _________ located on the surface of cells- used as markers to distinguish “self” cells from foreign

cells.

Antibody - produced by _______________- bind to foreign __________ & ______________ pathogens

Antigen and Antibody

Main Organs in the Immune System

Bone marrow - all RBC and WBC originate from bone marrow.

_____________ - T-cells mature __________ - destruction of old red blood cells

and holds a reservoir of blood

Lymphatic System

______________– contains lymphocytes & filters pathogens from the lymph.

____________– bring extra body fluid in the tissue back to the heart

_________ – fluid in the lymph vessels

Standard

10c. Students know how vaccination protects an individual from infectious diseases.

Koch’s Postulates

A procedure to ________ the ______of a ____________

1. The pathogen must be found in the host every case of the disease.

2. The pathogen must be isolated from the host and grown in pure culture.

3. When the pathogen from the pure culture is placed in a healthy host, it must cause the disease.

4. The pathogen must be isolated from the new host and be shown to be the original pathogen.

Passive vs. Active Immunity

_________ Immunity

-Ab not made by your own body.

Ex. From mother to baby during pregnancy

________ Immunity- Ab made by your body

Ex. _____________

-inject _______ or ______ pathogen to produce Ab.

Standard

10e. Students know why an individual with a compromised immune system (for example, a person with AIDS) may be unable to fight off and survive infections of microorganisms that are usually benign.

AIDS

________ ______________ _________

-caused by HIV (_________________________)

-HIV directly infects ___________ -> immune system is _____________.

-HIV can stay _________ for a long time w/o immediately destroying the cells.

-HIV can be transmitted through Infected blood and body fluids

Bubble Boy (David Vetter) 1972-1984

SCID (severe combined immunodeficiency)

Lacked _______ and lived in germ-free plastic room for 12 yrs. at Texas Children’s Hospital.

Died 2 weeks after unsuccessful bone marrow transplant.

Allergy

Immune system is _____________ and has an immune response to __________ things like _________, thinking that they are harmful invaders.

Autoimmune Disease

WBC of a person’s body attack its own body cells

Ex. __________________

Ch. 18

Viruses & Bacteria

Standard

10d. Students know that there are important differences between bacteria and viruses, with respect to their requirements for growth and replication, the primary defense of the body against them, and effective treatment of infections they cause.

Virus Structure

Biological particle composed of _____ or

_______ strand wrapped by a protein coat = __________

Characteristics Of Viruses

- not a cell (not considered to be a living thing)

- do not metabolize (no cellular resp.) - do not grow - do not respond to stimuli - ____________ ONLY inside __________= obligate intracellular parasite

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Viral Studies

most studies done on bacteriophages

(viruses that infect bacteria)

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Types of Viruses

1) DNA Viruses – usually directly produce RNA which will make a new viral protein. –may attach itself to host DNA & become dormant. The viral DNA is replicated along with host DNA during cell division.

(viral DNA -> RNA -> protein)

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Types of Viruses

2) RNA Viruses - some enter host cell and make proteins and new viruses directly

(RNA -> protein)

- some are retroviruses = contain reverse transcriptase (enzyme that makes DNA from RNA)

(RNA makes DNA -> RNA -> protein) Ex: AIDS Virus

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Viroids short single strands of

RNA WITHOUT capsid that can cause dieses in plants.

interferes with host cell’s function and

direct production of new viroids

Pass through seeds/pollens.

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Prions

- a piece of glycoprotein of approx. 250 AA that can cause other proteins to fold incorrectly.

- reproduce in mammalian cells; can reproduce without genes

- cause disease w/ long incubation period - causes Scrapie = degeneration of nervoussystem in sheep and goats - causes Kuru= degenerative nerve disease found in New Guinea Highland Tribes

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Prion (continued)

Ex. “mad cow” disease

In a healthy individual, the normal prion molecule is on the surfaces of cells, including neurons in the brain.

In an infected person or animal, the normal protein is converted into the misfolded prion, which accumulates in plaques that clutter the diseased brain.

Reproduction of Viruses

1) _______________

- Viruses infect host cell without immediately destroying the host cell

= virus is ___________

2) ______________- viruses infect host cell

destroying host cell immediately

=virus is __________

Viral Disease

Cannot be cured; only treated. Mostly, virus will be in body for good once infected. Can be treated by ___________ drugs

(NOT antibiotics).

Ex. _________________________________________

Two Kingdoms of Bacteria

_____________

-live in extreme conditions (such as hot springs or salt mines)

_____________

-common bacteria

Characteristics of Bacteria

______________ (no nucleus) Unicellular Autotrophic or heterotrophic Has ____________

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2 Main Types of Bacteria

Gram positive vs. Gram negative

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3 Different Shapes of Bacteria

1.Cocci = spherical

2.Bacilli = rod-shaped

3.Spirilli = spiral

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Grouping

Staphylo- = clusters (ex. staphylococcus)

Strepto- = filaments (ex. streptobacillus)

Diplo- = two

Structures of Bacteria

Cell wall - made of _____________ (polysaccharides cross-linked by short chain of AA); different from plant cell wall (cellulose)

___________ – protective layer around cell wall which helps them stick to surface.

_____– hair-like extensions which help to attach to a surface; used for exchanging genetic material.

___________ – circular DNA ___________ – whip-like tail

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Nutrition

Autotrophic

(Cyanobacteria)

Photosynthetic

Chemosynthetic

Heterotrophic

-decomposers = feed on dead organisms

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Respiration

_____________________– cannot survive in the presence of oxygen

_____________________– can live with or without oxygen (ex. E.coli)

_____________________– Must have oxygen to survive. (ex. Mycobacterium tuberculosis-lives in the lungs)

Reproduction of Bacteria

________________(asexual)

One cell splits into two cells that are identical to parent cell

________________(sexual)

One bacterium transfers

a copy of its DNA to another bacterium through a ________.

Results in new genetic combination.

Ex. Antibiotic resistance

Bacterial Diseases (Pathogenic Bacteria)

Can be cured by _________ if treated early.

Ex. Penicillin, tetracyclin

Pathogenic bacteria kill healthy cells by their _______________________.

Ex. _________, _______, ________

Antibiotic Resistance

Shows natural selection. Due to _________, if at least one bacterium

w/ a beneficial mutation against antibiotics survives (____________________), it reproduces every 20 min (____________) and the whole colony becomes resistant to antibiotics (_____________).

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Beneficial bacteria

1. _________________

Yogurt, cottage cheese, cream cheese, sour cream

2. ________________

-Used for recombinant DNA technology (ex. Insulin production)

3. _________________

-water treatment, oil spill clean-up by bacteria that break down oil