BLI System

BLI

* Consists of blood, bone marrow, lymphoid tissue
* Blood is the transporting fluid of our body
* **Lymphatic system**: both transport system and “barracks” of our immune system
* Study of blood: **Hematology**
* Study of Immune System: **Immunology**

3 functions of blood

* Transportation
* Regulation
* protection

plasma

* The liquid part of blood


* 55% of blood’s volume
* Yellow, straw colored
* 90% water, 10% (nutrients, salt, oxygen, hormones)


* Plasma protein contain:


* **Albumin: protein that helps keep correct amount of water in blood**
* **Fibrinogen: substance needed for blood clotting**

**Globulins:** proteins that form antibodies for protection from infection

red blood cells

* Also called erythrocytes
* Round, doughnut shape, no nucleus (can’t reproduce), created by bone marrow, called hematopoiesis
* Transport O2 and CO2 with an iron-containing red pigment called hemoglobin
* Lack of O2 stimulates production of RBCs
* Hemoglobin-protein
* Surface proteins determine blood type (A, B, AB, O)
* Spleen recycles old RBCs

white blood cells

* Also known as leukocytes
* 13-21 day lifespan, destroyed by lymph system, produced in bone marrow, about 6 billion
* 5 types, 2 classifications


* Able to leave blood vessels
* Pass through capillary walls
* Provide protection against bacteria, viruses, toxins

granulocytes

* contain granules in cytoplasm


* Neutrophils- 50-70%
* Fight off bacteria and infection
* Live 10-12 hours
* Phagocytes
* Eosinophils 1-3%
* Allergic response
* Parasites
* Basophils

agranulocytes

*  no granules


* Lymphocytes 20-25%
* T cells and B cells
* Monocytes 4-8%
* Macrophages (can change to dendritic cells in infection and inflammation)

platelets

* Also called thrombocytes
* Smallest of the formed elements in blood
* Colorless
* Lifespan 5-9 days
* Initiate clotting process, prevent blood loss from injured blood vessels, causes damage vessels to contract
* 150,000 - 450,000 in bloodstream

type a

40% of population

type b

11%

type ab

4% universal recipients

type o

45%, (38 O+, 7% O- universal donors)

antigens

foreign substance that enters your body are ON the surface of RBC

antibodies

produced by the immune system to fight off antigens are IN the plasma

group a

A antigens on RBC and B antibodies in plasma

group b

B antigens on RBC and A antibodies in plasma

group ab

Both A and B antigens on RBC, no antibodies at all in plasma

group o

No antigens on RBC, both A and B antibodies in your plasma

Rh factor

* Rh-protein called antigen found on RBCs
* Rh factor inherited
* Presence of the Rh factor= Rh-positive, absence of protein = Rh-negative
* 85% of white Americans, and 95% of African Americans are Rh-positive

immune system

* provides the weapons and the troops to protect body from invasion


* Antibodies
* Antigens 

innate immunity

* body’s inborn ability to fight infection


* 1st line of defense, prevents invasion
* Cannot “remember” general mechanisms of defense, sometimes kills healthy tissue with pathogens

adaptive immunity

* target specific invaders
* “Remembers”- improves protective responses by learning and changing

physical barriers

* prevents pathogens from invading


* Skin- surfaces difficult to penetrate (prevent invaders from getting inside the body)
* Mucous membranes- eyes, digestive, respiratory and reproductive system
* WBC’s and lymph capillaries trap invaders, fluids associated (tears, saliva, urine, sweat, oil, mucous)

general immune response

* Inflammation-increased blood flow and immune cells
* complement - marks pathogens for destruction
* Non-specific cellular responses

components of immune system

* Cells- 2nd line of defense against
* WBCs or leukocytes
* Granulocytes


* Neutrophils, Basophils, Eosinophils


* Agranulocytes


* Monocytes
* Macrophages: perform phagocytosis
* Lymphocytes: T cells and B cells

b cells

* humoral immunity


* Move through the bodies humors (blood and lymph)


* Differentiate


* Memory- stronger and faster response next time
* Effectors-fighters; dispatch antibodies

t cells

* cellular immune response
* Helper-activate immune response, call other cells
* Replicate and differentiate
* Memory cells
* Regulatory cells- tell other cells to stand down, control response
* Release cytokines
* Specifically one to activate Cytotoxic T cells