Circulatory Sytem- Blood Flashcards
What is haematology
Function of blood
1 transport
2 protection
3 regulations
Variation in volume 4-6L
1 body size
2 changes in fluid concentration
3 changes I electrolyte concentration
4 amount of adipose tissue
Blood made up of
Formed elements
- platelets
- Red blood cells
- white blood cells
Plasma
Blood plasma
92% water
Includes transporting nutrients gases and vitamins
Helps regulate fluid and electrolyte balance and maintain pH
Plasma proteins
These are the most abundant dissolved substances (solutes) in plasma
Formed by the liver
• expect globulin ( produced in plasma cells)
Three major categories
1 albumins
2 globulin
3 finruions?
Gases and nutrients
Most important- oxygen and carbon dioxide
Plasma nutrients include
Amino acids
Simple sugars
Nucleotide
Lips
Plasma electrolytes
They are absorbed from the intestine or released as a by product of cellular metabolism
Blood cells
All start with hematopoietic stem cells
Formation of blood cells
Red bone marrow
- connective tissue in cavities between the trabeculae (spongy bone)
- surrounded by sinusoids for nutrients and mean of exist for formed blood cells
Stem cell
- can
Erythrocytes
Carry o2 and co2 (survival)
Lack of nuclei and mitochondria
- able to squeeze through capillaries
- anaerobic fermentation only
One third hemoglobin
- oxyhemoglobin
- de oxyhemoglobin
Red blood cell production and its control
Low blood oxygen causes the kidneys and the liver to release erythropoietin which stimulates red blood cell production
Within a few days many new blood cells appear in the circulating blood
Negative feedback mechanisms takes 3-5 days and four major development
- reduced cell size, increasss cell number, symp
Erthropoiesis = erythrocytes
Effect red blood cell production
Iron
Vitamins b12 and folic acid
- required for dna synthesis
White blood cells - leukocytes
Protects against disease
Five types of wbc in two categories
1 granulocytes(granules)
- neutrophils
- eosinophils
-Basophils
2 agranulocycytes
-
Blood platelets
Platelets ( thrombocytes)
Lack neucleus
1/2 size rbc
Function
- secrete vasoconstriction
Form platelet plugs
Secrete a clotting factor
Clot dissolving enzyme
Secrete chemicals for inflammation
Hemostasis
Stop bleeding process
- vascular spasm
- platelets plug formation
-blood clotting (coagulation)
Vascular spasm
- constr
Extrinsic clotting mechanism
Chemical outside of blood vessel triggers blood coagulation
Triggered when blood contacts damaged blood vessel walls or tissues
Example of a positive feedback mechanism
Intrinsic clotting mechanism
Chemical inside blood triggers blood coagulation
Activated by blood trauma
Triggered by hageman factor XII
Has a cascade of clotting factors
Blood groups and transfusions
Antigens - a chemical that stimulates cells to produce antibodies
Antibodies- a protein that reacts against a specific antigen
Agglutination- clumping of red blood cells in response
Rh blood group
Group includes several Rh antigens or factors
-~ 85% Rh+
- 15% Rh-
Study of blood is
Hematology
Function of circulatory system
Transport
- oxygen to body
- carbon dioxide to the lungs
- nutrients
- hormones
Protection
- platelets for blood clotting
- white blood cells
- limit the spread of infection
Regulation
- heat
- fluid levels
- ph
Components of blood
Plasma-(55%)
Formed elements (45%)
- platelets
-red blood cell ( erythrocytes)
- white blood cells (leukocytes)
• granulocytes
- neutrophils
- eosinophils
- basophils
• agranulocytes
- lymphocytes
- monocytes
Erythrocytes (red blood cells) structure and function
Two functions
• pick up oxygen from the lungs and deliver to tissues
•pick up carbon dioxide from tissue and deliver to lungs
Contain hemoglobin that transport of oxygen and carbon dioxide and gives blood is red colour
Includes glycolipids on the outer surface that determines blood type
No mitochondria no nucleus
Platelets
Function
- secrete vasoconstriction
- form platelet plugs
-Secrete a clotting factor
- clot dissolving enzyme
- secrete chemicals for inflammation
- destroy bacteria
- secrete growth factors
The heart two major divisions
Pulmonary circuit: right side of heart
Systemic system: left side of heart
Heart chambers
Right and left atria
Right and left ventricle
Heart three layers
Epicardium
Myocardium
Endocardium
Plasma proteins
Albumum accounts for 60% of the plasma proteins. Its main function is to assist in the maintenance of colliod osmotic pressure.
Whereas globulin account for 36% and can be further broken up into three sub-categories; alpha globulins beta globulins and gamma globulins. The alpha and beta transport lipids and fat-soluble vitamins, whereas the gamma constitute the antibodies of immunity
fibrinogen makes up the remaining 4% and plays a key role in blood coagulation
