blood and hematopiesis Flashcards
(98 cards)
Specialized connective tissue consist of cells and extracellular fluid (plasma)
blood
- Plasma gives support and nutrients to the cells present in our blood.
Functions of Blood
○ Transport of oxygen (in different
tissues/ cells of the body) and CO2 (transport back to the lungs).
○ Transport of nutrients and hormones to different parts of the body - to sustain the needs of a person.
○ Removal of metabolic waste.
○ Regulates body temperature and maintenance of acid-base balance - to maintain the body temperature of 37°C.
○ Defense against infection.
■ Example: WBC phagocytize foreign substances.
what are the major cells of the blood
- Erythrocytes aka RBC
- Leukocytes aka WBC
- Thrombocytes aka Platelets
composition of whole blood
PLASMA (55%)
water (92%)
proteins (7%)
- albumin (58%)
-globulins (37%)
- fibrinogen (4%)
other solutes (1%)
BUFFY COAT (< 1% of whole blood)
platelets (150-400 thousands)
leukocytes (4.5-11 thousands)
- neutrophils 50-70%
- lymphocytes 20-40%
- monocytes 2-8%
- eosinophils 1-4%
- bsophils 0.5-1%
RBC (44%)
4.2-6.2 million per cubic mm
ratio of the whole blood of RBC to the volume of blood.
hematocrit
*it is measured by comparing the RBC vol to the plasma volume
What happens to blood after centrifugation?
can see the composition of blood, separating into layers based on density.
What type of tube is used for blood centrifugation?
anticoagulated or non-coagulated tubes
The fluid portion of blood when it is outside the circulatory system and has no anticoagulant.
serum
The fluid portion of blood when an anticoagulant is present.
plasma
A thin, gray-white layer between plasma and RBCs, containing WBCs and platelets.
buffy coat
composition of plasma
- Plasma proteins
- Nutrients
- Respiratory gases
- Nitrogenous waste products
- Hormones
- Electrolytes
what are the Major plasma proteins
Albumin
Globulins (a- and ß-globulins)
Immunoglobulins (antibodies or y-globulins)
Fibrinogen
Complement proteins
Most abundant plasma protein which maintains the osmotic pressure of blood
Albumin
Includes transferrin and other
transport factors such as fibronectin, prothrombin, other coagulation factors, lipoproteins and other proteins entering blood from tissues.
Globulins (a- and ß-globulins)
transport factors such as
- fibronectin
- prothrombin
- other coagulation factors
- lipoproteins
- other proteins
Antibodies used to fight off infection and for defense mechanisms.
Immunoglobulins (antibodies or y-globulins)
- secreted by plasma cells and they are the mature B cells
Important information of fibrin clot in the hemostasis. (clot formation)
Fibrinogen
Involved in the defense system which is important during inflammation and destruction of microorganisms.
Complement proteins
Normal pH of the plasma
pH 7.4
Hematopoiesis in greek
haima - blood
poiesis - making
= blood making
A continuous regulated process of blood cell production.
Hematopoiesis
Includes:
cell renewal
proliferation
differentiation and maturation of cells
what are the phases of hematopoiesis
- Mesoblastic (Yolk Sac) Phase
- Development of primitive (old) erythroblast from mesodermal cells.
○ Origin from the mesodermal cells in the fetus.
[first phase, happening early in the embryo.
Where it happens: In the yolk sac (a temporary structure in the embryo).
What happens: Primitive (early or basic) red blood cells are formed from special cells called mesodermal cells.
These early red cells are not like adult ones—they’re the first version, just to get things started.] - Hepatic Phase
- Occurs during second trimester, liver is the major site of cell production with minor help from spleen.
- Beginning of definitive hematopoiesis.
[beginning of “definitive” hematopoiesis—which means the production of real, functional blood cells like in adults.] - Medullary (Myeloid) Phase
- Start at 5th month of fetal development and remain the primary site of hematopoiesis.
● Production occurs at the developing bone marrow cavity.
○ The development of the blood
cells (hematopoiesis) at the bone marrow cavity of the developing fetus.
○ Site of hematopoiesis for young.
[The bone marrow takes over as the main site of blood cell production, and this continues for life.
Blood cells of all types (RBCs, WBCs, and platelets) are now made in the developing bone marrow cavity.]
What is the main site of blood cell production in the second trimester?
liver, with minor help from the spleen
What are the three blood cell lineages?
Erythroid lineage → Produces RBCs.
Myeloid lineage → Produces WBCs & platelets.
Lymphoid lineage → Produces early lymphocytes .
When does the bone marrow become the main blood cell factory?
during the Medullary (Myeloid) Phase, starting in the 5th month of fetal development.
✔ Blood cell development (hematopoiesis) shifts to the bone marrow.
✔ The bone marrow becomes the primary site of hematopoiesis for life.
blood cells are produced in the Medullary Phase:
-Red Blood Cells (RBCs)
-White Blood Cells (WBCs)
-Platelets