1. Blood and Lymphatic System
Biology 20

2. Blood
Blood is a connective tissue as it links all the cells and organs in the body
Blood consists of two elements:
Fluid portion: plasma (consists of water, dissolved gases, proteins, sugars, etc)
Solid portion: formed portion (consists of red blood cells, white blood cells and platelets)

3. Make up about 44% of the total volume of blood
Specialized for oxygen transport
Each RBC contains about 280 million hemoglobin molecules
Have no nucleus
Live only 120 days
If there are too few RBC or too little hemoglobin a condition called anemia occurs

4. Less numerous than red blood cells (outnumber white 700 to 1)
Have a nucleus and appear colourless
Part of the body’s response to infection

5. Leucocytes (White Blood Cells)
Leucocytes are divided into 3 groups
1.  Granulocytes
- neutrophils, basophils, and eosinophils
- engulf and destroy foreign bodies (i.e. bacteria, fungi, allergens, and parasites)
2.  Monocytes
- leave bloodstream to become macrophages
- engulf and destroy bacteria
3.  Lymphocytes
- produce antibodies to defend against infection

7. Thrombocytes (Platelets)
Do not contain a nucleus
Play a key role in clotting blood
When injury occurs at a blood vessel substances are released that attract platelets
The platelets will rupture and combine with other blood components to create an enzyme: thromboplastin
If calcium ions (Ca+) are present the thromboplastin will react with prothrombin to produce thrombin

8. Thrombin reacts with fibrinogen to produce fibrin
This will then form a mesh of strands around the injury which traps the blood and makes a clot

10. Fluid portion of blood
Blood cells are suspended inside
Carries blood cells and other substances (refer to table 8.3 on page 284)
Transports carbon dioxide

11. Transport
One of the primary functions
Transports nutrients, hormones, waste, gases
Homeostatic Regulation
Regulates our body temperature
Blood coming to the skin is warmer than the skin and heat can be lost this way (refer to figure 8.19, pg 286)

12. If the body becomes too warm it must rid itself of heat
It does this by dilating the blood vessels close to the skin (vasodilation) which increases the amount of heat lost from the blood through the skin
If the external environment is cold the blood vessels near the surface constrict (vasoconstriction) so that no extra heat is lost

13. Countercurrent Heat Exchange
Occurs in deep arteries and
veins to maintain
a steady temperature
in the body

14. Crash Course!
Blood

15. Biology 20

16. The lymphatic circulatory system is a network of glands and vessels that carry lymph
Lymph is made of interstitial fluid and is similar to plasma
The lymphatic system maintains the balance of fluids in the body and defense against infection

17. helps WBC’s protect the body against infection
lymphocytes
lymph nodes = help trap and destroy bacteria
Special white blood cells called lymphocytes mature in the lymph nodes

18. During blood circulation, some of the plasma leaves capillaries and enters the interstitial fluid
Much of this interstitial fluid is absorbed into the vessels of the lymphatic system
The vessels are a one-way circulatory system (unlike the cardiovascular system) which transport lymph from closed-ended tubes toward the heart

20. 3 lines of defense:
Barriers to keep pathogens out
General defenses against a wide variety of pathogens.
Specific defenses against certain pathogens

21. THE DEFENSE SYSTEM
There are 3 lines of defense the body uses against invaders:
Barriers to keep pathogens out
General defenses against a wide variety of pathogens.
Specific defenses against certain pathogens.

22. First line of defense
All of the physical and chemical barriers
Skin, eyelashes, cilia, tears, stomach acid, etc.
Second line of defense (ie. non-specific defense)
Includes three type of white blood cells: macrophages, neutrophils and monocytes
These cells all use phagocytosis to kill foreign particles

23. All of the physical and chemical barriers
Skin, eyelashes, cilia, tears, stomach acid, etc.

24. Second Line of Defense Includes macrophages
These cells all use phagocytosis to kill foreign particles

25. Third Line of Defense (ie. specific defense)
Use of antibodies against invaders
Antibodies are proteins that recognize invaders and act to destroy them

26. Third Line of Defense aided by lymphocytes: B cells and T cells
B cells – B lymphocytes; mature in the bone marrow; create antibodies
T cells – T lymphocytes; mature in the thymus gland

27. Third Line of Defense
monocyte = travel from bloodstream into tissues and become macrophages
lymphocyte = B-cells and T-cells (3rd line)
neutrophil = target bacteria and fungi
eosinophil = large parasites; allergy response
basophil = inflammatory response

28. T CELLS
Helper T cells = recognize the antigen and stimulate the action of B cells and other T cells
Killer T cells = stimulated by helper T cells; kill the infected cells
Suppressor T cells = make sure that no normal tissue is destroyed
Memory T cells = remain in the bloodstream; act quickly if the invader with the same antigens returns

29. On all foreign invaders there are antigens found on the surface of the cells
Antigens are an identification system that the T and B cells can use to recognize different invaders

30. The antibodies produced have the same shape as an antigen receptor for a specific antigen
Memory B cells stay around to repeat an immune response if necessary

31. Third line of defense
Use of antibodies against invaders
Antibodies are proteins that recognize invaders and act to destroy them
On all foreign invaders there are antigens found on the surface of the cells
Antigens are an identification system that the T and B cells can use to recognize different invaders
The antibodies produced have the same shape as an antigen receptor for a specific antigen
Memory B cells stay around to repeat an immune response if necessary

32. BLOOD TYPES
ABO system – classification of human blood types based on the presence or absence of A or B antigens
Blood type is an inherited characteristic
There are four different blood types:
A, B, AB, O
Refer to figure 8.3 and Table 8.4 on page 296

33. Each blood type has a glycoprotein or marker attached to its cell membrane
Blood type A - has an A glycoprotein = “A marker”
Blood type B - has a “B marker”
Blood type AB - has both A and B markers
Blood type O - has neither

34. These markers act as antigens and antibodies will be made to attack foreign invaders
Blood Type
Antigen on Red Blood Cells
Antibody in Plasma A
Anti-B B
Anti-A AB
A and B
None O
Anti-A and Anti-B

36. Antibodies act on the invading antigens
This causes agglutination - clumping of the blood; will occur when incompatible blood types are mixed
This is deadly
AB = universal recipient
O = universal donor

37. THE Rh SYSTEM Rh Factor – another group of antigens found on RBC
Will either have this antigen and be rhesus positive (Rh+) or won’t and will be rhesus negative (Rh-)
People with Rh- blood do not have Rh antibodies but could develop them (Rh+ people do not have antibodies)
Rh- people can donate blood to Rh+ people but shouldn’t receive Rh+ blood
This becomes a problem when a Rh+ baby is born to a Rh- mother (Refer to figure pg 297)

39. IMMUNE SYSTEM DISORDERS
Autoimmune disease
body attacks itself
often mutated T and B cells are produced that are capable of attack but we have suppressor T cells that hold them back
if they fail the T and B cells will attack normal body cells
Examples:
rheumatoid arthritis – immune response against the connective tissues of the joints (figure 8.32 pg 298)

40. type 1 diabetes – immune reaction against the insulin-producing cells of the pancreas
multiple sclerosis – attack the myelin sheath of nerve cells
Allergies
when your immune system mistakes harmless antigens for harmful invaders
reactions can be mild (tissue swelling) or severe (anaphylactic shock)