Blood Flashcards
What is happening in systemic circulation?
Pulmonary?
Blood is pumped from left chambers of heart to perfuse entire body with oxygenated blood
Blood is being pumped back to the lungs to be reoxygenated
Circulatory system is mostly closed (meaning blood remains inside) exception?
Circulatory system can sometimes be where immature forms reach maturity and then leave the system to enter other tissues (or if they are immune cells fighting infection)
What is microcirculation?
Only place where this happens?
Phase of circulation where exchange of O2, CO2, glucose, nutrients, waste take place
This exchange only happens in capillaries
Difference in composition between arteries and veins
Arteries: more smooth muscle and elastic fibers
Veins: thicker tunica adventitia and are typically larger than arteries
~arteries tend to be stiffer, veins tend to be softer
3 different structural types of capillaries?
Continuous (non-fenestrated), fenestrated, and sinusoids
- Fenestrated capillaries structure and function
2. Sinusoids structure and function
- Looks like tiny holes are poked into the endothelial cells; allows direct passage between blood and tissue external to capillary (most common)
- Very large gaps (almost looks ripped); gaps lead to large blood filled spaces in certain tissues where there is a lot of filtration of blood (liver, spleen, bone marrow, erectile tissue)
What kind of endothelial cells are present in CNS capillaries?
What is it called?
What cannot enter the CNS?
Not fenestrated; they have tight junctions (zona occludens)
Blood brain barrier; lipids diffuse, hydrophilic substances via transmembrane protein transporters
Immune cells (aka CNS is immune privileged)
What is contained in lymph fluid?
Difference between course of lymphatic vessels and circulatory vessels?
Some types of blood cells (mostly lymphocytes), and different types of macromolecules/debris that was removed from tissue
They run in parallel with each other, but lymph is uni-directional
What happens at lymph nodes?
Lymph fluid is filtered by WBCs and WBCs related to the immune system can be activated
Name 5 lymphatic organs
Bone marrow, thymus, spleen, lymph nodes and lymphatic nodules
What happens at the following lymphatic organs:
- Spleen?
- Thymus?
- Nodules?
- Blood is filtered by WBCs and can respond to pathogens in blood
- Where T-lymphocytes matures
- Clusters of lymphocytes throughout the body where immune response to local tissue occurs
What is the buffy coat?
The very thin layer between plasma and RBCs after centrifuge that contains WBCs
Plasma vs. serum?
Plasma contains fibrinogen (clotting factors); serum is what you get if blood was allowed to clot before centrifuging
Normal RBC is 44%; if it is less than 44%, what does that indicate?
either RBCs are not being produced, there is a hemorrhage, or something is breaking RBCs down that should not be
- Shape of RBCs
- Size of RBCs?
- Normal hematocrit % range
- Why was nucleus removed during cell formation of RBC?
- Life span?
- B concave shape
- ~7-8 um (slightly narrower than capillary diameter)
- ~42-47%
- Once RBCs mature, they dont need a nucleus because they are just transporting oxygen
- ~120 days (made by stem cells because they do not undergo mitosis)
Technique used to examine normal vs abnormal conditions of RBCs?
Blood smear
what is hemoglobin?
Disorders of hemoglobin:
- Anemia function and causes?
- HbH description and causes?
- HbA1c
- Sickle cell anemia
Part of RBC that transports oxygen
- Reductio in RBC number or function; insufficient cell production, excessive cell loss (hemorrhage), deficiency in iron, B12, folic acid.
- No alpha chain (which is present throughout life)only beta (which is mostly post natal); manifests mild hemolytic anemia= reduced o2 carrying capacity
- Type of blood subtype that normally binds glucose irreversibly; elevated in diabetics
- Gene mutation in beta chain of HbA. (Replaced valine for glutamate changes shape) makes RBC less able to carry oxygen and less flexible so it can get lodged and cause occlusions
Different blood types of due to variations of
Carbohydrate groups that are attached to the glycoprotein on RBC membrane
O blood types can give blood to __ and receive from?
Give blood to anyone, receive only from O.
Difference between Rh positive and negative
When will mother attack fetus?
Rh negative lack D antigen in their Rh protein
When mother is Rh negative and fetus is Rh positive (mothers immune system doesnt recognize D antigen) (erythroblastosis fetalis)
Platelets:
- Structure
- Origin
- Function
- ___ are secretory vesicles that mediate clotting
- Smaller than RBCs, round biconvex shape.
- Formed from fragments of megakaryocytes
- Platelets induce clots and seal off injured blood vessels; they can contract (key event in clot retraction and healing of damaged vessels)
- Granules (inclusions)
Blood clotting
5 steps
- Plasma proteins attach to damaged area; this attracts platelets which form platelet plug
- Platelets release ADP containing granules to attract more platelets and release serotonin (vasoconstrictor)
- Formation of fibrin protein filaments and fibrin mesh-like network traps blood cells and stops blood flow
- Platelets contract which causes retraction of the clot
- As blood vessel wall is repaired, plasminogen is activated which activates plasminogen to become plasmin (which degrades the clot)
What types of leukocytes are neutrophils, basophils and eosinophils?
Granulocytes (secretory vesicles that stain intensely)
Neutrophils:
- Microscope ID?
- Function?
- Mechanism of function?
- Nucleus has many segments or lobes
- Phagocytose and destroy microbial cells
- Receptor mediated process (neutrophil binds to surface of endothelium); granules contain enzymes for lysosomal digestion of phagocytosed microbes.
~lactoferrin = lysosomal enzyme
~neutrophils die and form pus
Basophils
- Microscope ID?
- Function?
- Have similar function to?
- Nucleus has 2 or more segments or lobes (granules have intense purple stain)
- Release heparin (anticoagulant), histamine, and leukotrienes (causes smooth muscle contraction)
- Mast cells of connective tissue
Eosinophils
- Microscope ID?
- Function?
- Located at sites of inflammation and where else?
- Nucleus has 2 segments or lobes typically (granules stain red)
- Release substances to attack parasites; releases histaminase to counter edema effect due to release of histamine by mast cells
- In connective layer tissue that is exposed to outside world (skin, vagina, etc.)
Two agranulocyte WBCs?
Monocytes and lymphocytes
Monocytes
- Microscope ID?
- Function?
- C shaped nucleus, cytoplasm staining color is comparable to RBCs. (Remember, no granules; also no lysosomes)
- Performs antigen presentation to immune cells (mainly lymphocytes), migrate across endothelium to enter connective tissue and mature into macrophages (typically remain in tissue rather than returning to blood)
Define diapedesis
Migration across endothelium
Lymphoctes
- Microscopic ID?
- Function (3 types of lymphocytes)?
- Large round nucleus that fills most of cell; blue/gray staining cytoplasm
- B lymphocytes= originate and mature in bone marrow; can differentiate into plasma cells that make antibodies (immunoglobulins)
- T lymphocytes= mature in thymus (more on t cells later)
- NK cells= only granular lymphocytes, same stem cells as B and T cells, release chemicals to kill virus infected/tumor cells
T Cells
3 types and function?
- Helper T cells - activate other lymphocytes
- Suppressor T cells - suppress lymphocyte activity
- Cytotoxic T cells- release chemicals that kill microbes, other foreign cells (transplant tissue) and tumor cells
3 other types of blood cells present in connective tissue and their function?
- Macrophages - phagocytosis and antigen presenting (to bind and activate other immune cells present)
- Mast cell- inflammation; releases substances that attract other blood cells into tissue
- Plasma cells- make and release antibodies against foreign cells
What is hemopoeisis?
Locations of hemopoesis:
- Post natally (when does it begin here)
- During embryonic development
- During 2nd trimester
Production of blood cells and platelets
- Bone marrow - 3rd trimester
- Yolk sac
- Liver (erythrocytes); spleen (leukocytes)
