Notesale: Turn your study into money

Document Preview

Extracts from the notes are below, to see the PDF you'll receive please use the links above

---

Chapter 15 – Innate Immunity
1
...

 (1) Pathogen needs to gain access, either by penetrating the surface of the skin or through portals of entry
...

 (3) Pathogen needs to evade the body’s adaptive defense mechanisms long enough to produce harm
...
Explain the phrases species resistance and innate immunity
...

 Innate immunity refers to only the first two lines of defense because they are present at birth
...
Identify the physical and chemical aspects of skin that enable it to prevent the entrance of pathogens
...

o Also contains dendritic cells, which have fingerlike processes waiting to catch any invaders
...

o Blood vessels are delivering any needed defensive cells and chemicals
...

 Skin also contains sebaceous (oil) glands, which secrete sebum to lower pH for the death of bacteria
...
Explain how mucous membranes protect the body both physically and chemically
...

 The deeper connective tissue layer provides mechanical and nutritive support for the epithelium
...

o Ciliated columnar cells help propel mucous up the lungs
...
Describe the lacrimal apparatus and the role of tears in combating infection
...

 Lacrimal glands secrete tears to flood and wash the eye with lysozyme and carry irritants away
...
Define normal microbiota and explain how they help provide protection against disease
...

o All of these resist the growth of pathogens
...
Discuss the components of blood (plasma and cells) and discuss their functions in the body’s defense
...

o Plasma proteins are involved in blood clotting and inflammation
...

 Leukocytes or white blood cells: Releases toxins and performs phagocytosis
...
Name and describe the six stages of phagocytosis
...
)
 Adherence: phagocytes bind to pathogen via complementary chemicals, such as glycoproteins
...

 Maturation: a series of organelles in the phagocyte fuse with new phagosomes to form digestive vesicles
...

 Killing: Along with 30 different enzymes, such as lipases, proteases, nucleases, destroy the microbes
...

9
...






Eosinophils: Often, they secrete antimicrobial chemicals to kill worms
...

Natural Killer Lymphocytes (only one cannot undergo phagocytosis; the other two can)
o Works by secreting toxins onto the surfaces of virally infected cells and tumors
...

o They can also generate a neutrophil extracellular trap (NET) to capture gram+ and gram- bacteria
...


10
...

 (TLRs) are proteins in the membranes of phagocytic cells that act as an early warning system, triggering the
body’s responses to any molecule shared by viruses or bacteria but absent in human
...

11
...

 Interferons are proteins released by host cells to nonspecifically prevent the spread of viral infections
...

 Alpha and beta interferons bind to neighboring uninfected cells
...

12
...
You don’t need to know every single
molecule in the classical pathway, just the key features: what triggers it, how it kills microbes
...
The result of full complement activation is lysis of foreign cells
...

 Classical Pathway
o Activated by C1 enzyme when it binds to an antibody-antigen complex
...

 Alternative Pathway
o Activated by the cleavage of C3 enzyme into C3a and C3b
...
[The cell dies in the exact same way as classical
...

13
...

 The benefits of inflammation are increased dilation of blood vessels, attraction of immune cells, and
beginning of wound repair
...

 There is increased vasodilation in injured tissues in response to Bradykinin and Histamine
...

 Increasing heat and redness is given off by the increased blood flow
...

 Pain is experienced as nerve endings are stimulated
...
Explain the benefits of fever in fighting infection
...




---