Blood Flashcards
How much blood does the average human have?
5 liters of blood
What are formed elements?
Various types of blood cells and cell fragments
What is blood plasma?
The fluid matrix and all of the dissolved materials within the fluid matrix.
What makes up formed elements?
Erythrocytes (red blood cells), leukocytes (white blood cells), and platelets.
What is plasma made up of?
92% water, 7% plasma proteins, 1% ions (electrolytes), 0.3% nutrients, dissolved gases, waste products, and hormones.
Erythrocytes
red blood cells; most common of the formed elements; 250 million cells per drop of blood; primary function is to transport large quantities of oxygen throughout the body; biconcave disc.
Characteristics of erythrocytes
no nucleus, do not have usual organelles, cannot repair or maintain themselves, average lifespan is 120 days, packed full of hemoglobin
Hemoglobin
a protein molecule that can efficiently carry oxygen
Characteristics of hemoglobin
it has four heme units, which contain iron; oxygen molecule binds to each heme unit, so a hemoglobin molecule can carry four oxygen molecules
Leukocyte
White blood cells
Characteristics of leukocytes
larger than red blood cells, have a nucleus and all normal organelles, potential to live for years, can move independently through the body tissues, most good at endocytosis, some produce antibodies
Platelets (thrombocytes)
cell fragments made of cell membrane and cytoplasm, they help prevent blood loss
Hemopoisis
the process of making new formed elements; occurs in red bone marrow
Hemostasis
maintaining blood volume by minimizing loss due to injury
Hemostasis primary mechanisms
Vascular spasm, platelet plug formation, and blood clot formation
