Blood Flashcards
What does blood transport?
Oxygen, nutrients, wastes, carbon dioxide, and hormones
Functions of Blood
Transportation
Defense
Regulatory Functions
What does blood defend against?
Blood defends against invasion by pathogens
What does blood regulate?
Blood regulates body temperature, water-salt balance, and the body’s pH ~ 7.4 (slightly basic)
What is blood?
Blood is a fluid connective tissue.
What is blood made out of?
Formed elements - red blood cells, white blood cells, and platelets
Formed Elements
Cells and cell fragments that are produced in red bone marrow and suspended in a liquid called plasma. Formed elements are red blood cells, white blood cells, and platelets.
Plasma
A liquid, rich in protein, that suspends the formed elements.
Erythrocytes
Red blood cells
Leukocytes
White blood cells
Thrombocytes
Platelets
Structure of Red Blood Cells
Red Blood Cells lack a nucleus and have very few organelles, but their biconcave shape increases surface area.
What does a red blood cell contain?
Each red blood cell holds about 280 million hemoglobin molecules (protein) that bind 3 molecules of O2 each.
Hemoglobin
Protein molecule that binds to oxygen and carries it. Found in the red blood cells.
How are red blood cells produced?
Red blood cells are produced in red bone marrow and live about 120 days. Erythropoietin hormone is secreted by kidney cells and moves to red marrow when oxygen levels are low, stimulating production of more red blood cells.
Erythropoietin
A hormone that stimulates production of red blood cells in our red bone marrow when oxygen levels are low.
How are old red blood cells disposed of?
The liver and spleen dispose of old red blood cells.
Anemia
Condition resulting from too few red blood cells or two little hemoglobin, causing one to feel “run-down”. This can also be caused by a lack of iron.