Unit 2: Blood Flashcards
Functions of blood
- Transport of nutrients, hormones, waste
- Maintenance of body pH (level of acidity)
- Regulation of body temperature
- Involved in body defence and immunity
- Blood clotting
Hematopoeisis
All blood cells start from a precursor cell called the pluripotent stem cell ( = hemocytoblasts) multipotent hematopoietic
From there, these stem cells can differentiate into different types of blood cells the myeloid stem cell or the lymphoid stem cell
Blood (extracellular fluid)
blood plasma 55%: water (91%), plasma proteins (7%), other solutes (glucose, hormones, and calcium, 2%)
formed elements 45%: red blood cells, platelets, white blood cells
Blood plasma
Liquid portion of blood
90% water
7% plasma proteins: made in the liver and then stay in the bloodstream:
albumin (largest protein)
immunoglobulins
fibrinogen
2% other substances
electrolytes (ions), nutrients, hormones, gases, waste products
plama proteins (7%)
albumin: thicken blood and viscosity, causes blood pressure increase, regulates blood pressure
immunoglobulins: antibodies
fibrinogen: forms blood clots in the body
Cellular components of blood
formed from the red bone marrow of spongy bone
Erythrocytes (red blood cells)
No nucleus
Transports oxygen and carbon dioxide around the body (using hemoglobin)
Leukocytes (white blood cells)
Part of the body’s defense
Different types, each with a specific role
Platelets (thrombocytes)
Fragments of special bone marrow cells – not cells!
Contains no nuclei and no hemoglobin * Involved in blood clotting
leukocytes
-fights against disease and infection
-Each white blood cell fights against a different type of infection
types of white blood cells
Neutrophils: engulf and secrete Lysosome (antibacterial)
eosinophils: anti inflammatory and anti parasitic actions
Basophils. These small cells seem to sound an alarm when infectious agents invade your blood. Release inflammatory molecules (ex. histamine (allergies) )
Monocytes. They have a longer lifespan than many white blood cells and help to engulf particles.
Lymphocytes.
T cells: recognize and kill foreign cells
B cells: produce antibodies
Erythrocyte vs platelet
A type of blood cell that is made in the bone marrow and found in the blood. Erythrocytes contain a protein called hemoglobin, which carries oxygen from the lungs to all parts of the body.
platelet They help form blood clots to slow or stop bleeding and to help wounds heal. A tiny, disc-shaped piece of cell that is found in the blood and spleen. Platelets are pieces of very large cells in the bone marrow called megakaryocytes.
Blood viscosity
= thickness of the blood
Amount of blood cells and proteins will affect the viscosity of blood
Changes in viscosity will affect the circulation of blood in the cardiovascular system
stimulus for erythrocyte production
when oxygen decreases the erythropoietin hormone is released by certain cells of the kidneys
erythropoietin: stimulates the red bone marrow to produce more red blood cells
occurs when:
decreased blood volume (from blood loss, dehydration, etc.)
low oxygen supply
