Host Defense Mechanisms, pg. 72/73

23 terms by brittany_2121

Create a new folder

Advertisement Upgrade to remove ads

Surface barriers, inflammation, and immune response

What are the 3 host defense mechanisms?

Surface barriers

What is the first line of defense?

The first line of defense includes...

Epidermis and mucosa, secretions (mucus, saliva, lacrimal, etc.), and normal microbiota on the skin and mucosa

The epidermis and mucosa are...

A good barrier when intact and have ciliated cells (lower respiratory)

Normal microbiota on skin and mucosa...

Colonize niches; out-compete pathogens, disease may result if killed (antibiotics, etc.)

Inflammation

What is the second line of defense?

The second line of defense includes...

Inflammatory mediators (bradykinin, histamine, etc.) and complement

Inflammatory mediators...

Alter blood flow, capillary permeability, etc., and attract phagocytic WBC's by chemotaxis

PMN's (neutrophils) come...

First, eat MO's, and release enzymes

Macrophages come...

Later, efficient killers and eaters, release toxic forms of oxygen (NO, nitric oxide), produce interleukins (IL); enhance response

Complement

Serum proteins that can become activated; help immune system destroy invaders

The Immune Response

What is the third line of defense?

Antigens (from MO) stimulate...

lymphocytes (B cells and T cells

B Cells

Produce plasma cells and make antibodies

Antibodies

Proteins that bind to antigens

IgC

Circulates in blood; Attaches to bacteria, viruses and Inactivates toxins

IgA

In secretions

IgM

Clumps antigens together

T Cells

Cell-mediated response (cell-to-cell contact), Kills MO's and regulate immune response, Remove abnormal or virus-infected cells

Immunization (Vaccination)

Antigens are injected; MO's (weakened or dead), components, neutralize toxins; Stimulates immune response (B cells, T cells, and memory cells)

Memory Cells

Confer immunity (future)

DPT (Diptheria, Pertussis, Tetanus)

Contains cells fragments from Bordetella pertussisi and toxoids made from Diptheria and Tetanus exotoxins

Toxoids

Inactivated by heat, formaldehyde, etc.; Still antigenic: body produces antitoxins (antibodies) against them

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set