1. Chemical and Biological Injury

2. Chemical Injury Poison to the cell
It is the dose that makes something poisonous
Affects permeability of the cell membrane
Tylenol can by poisonous in high concentrations, lead is poisonous is small amounts

3. Chemical Injury Vitamins Vitamin C
you can take as much as you want (as is B)
It is water soluble and passes through you
Vitamin E
fat soluble and can be toxic to the liver (as can A,D,E,K)
Carcinogens
Chemicals that lead to cancer (CA)

4. Biological Injury Parasites world-wide problem malaria
are not common in the USA
person probably out of the country

5. Biological Injury

6. Biological Injury Bacteria: tiny, primitive cell lacking a nucleus
too large to get inside of our cells
they usually cause disease through a release of toxins
take in glucose and release toxins which make you sick

7. Biological Injury What defenses do you have against bacteria? Mucus
Protects every cell
Conditions for optimal bacterial growth
Heat
98.6*F
Ideal for binary fission
reproduction
Moisture
Food

8. Defense Strategies
Besides mucus cells, our bodies have another defense mechanism
Immune response
First Line of Defense Against Bacteria
Neutrophils
Most common type of white blood cells
Circulate in blood then move to tissue
Attack and consume bacteria through phagocytosis
Contain numerous lysosomes filled with digestive enzymes

10. Defense Strategies Provide chemical signals called CYTOKINES
carry messages between the cells of the immune system
Circulate in blood then move to tissue
“Watch dogs” of your immune system
Main constituent of pus

11. Defense Strategies

12. Defense Strategies 2nd Line of Defense Monocytes
Another type of white blood cell
Slower moving but much more lethal
By the time monocytes arrive, most of the bacteria is already dead
They would be the battleships of the military analogy

13. Defense Strategies
If monocyte level is elevated on a blood test, the infection has been going on for a while
Often elevated in chronic bacterial infections
(most bacterial infections are acute)

14. Both neutrophils and monocytes are produced in the bone marrow
Most effective production occurs when you are sleeping
Why?
You are using the least amount of energy which can then be used to produce wbc
What is a common problem when students go to university?

16. Other Defenses Lymphocytes T-cells attack cells that contain viruses
B-cells
produce antibodies against antigens
Eosinphils
release enzymes for fighting parasites
destroy allergens

17. Other Defenses Basophils Least common
Prevent blood from clotting too quickly
Contains vasodilator histamine
Increases blood flow to the tissues

18. Inflammation Most common and visible response to injury
Serves to destroy or remove bacteria and diseased tissue
Inflammation of tissue or organ is designated by the suffix
itis

19. Inflammation 2 stages vascular arterioles constrict and then dilate
movement of plasma into the interstitial space
causes edema (swelling)
cellular
release of histamine
increases capillary permeability

20. Inflammation Signs Redness arterioles dilate
circulation to the site increases
Heat
results from local vasodilation
fluid leakage into interstitial spaces
increased blood flow

21. Inflammation Pain pain receptors are stimulated by swollen tissue
Edema (swelling)
local vasodilation
fluid leakage
Loss of function
occurs as a result of edema and pain

22. Kinins
proteins in blood that increase blood flow
make it easier for fluids to pass through small capillaries
stimulate pain receptors
activate white blood cells