Chapter 6: Blood Flashcards
(32 cards)
capillaries
tiny vessels that connect arteries to veins
arteries
from the heart to the capillaries and tissues of the body
veins
carry blood from tissues and capillaries to the heart
what are the walls of capillaries composed of?
endothelium (simple squamous epithelium) and basement membrane
three layers of arterie or vein walls
tunica intima (next to the lumen) tunica media tunica externa
tunica intima is composed of
endothelium and a layer of connective tissue
tunica media composed of
composed of smooth muscle tissue and elastic connective tissue
tunica externa is composed of
dense connective tissue
structural differences between arteries and veins
tunica media is thicker in arteries than in veins
tunica externa thicker in veins than arteries
plasma
liquid portion of blood composed mostly of water
formed elements of blood
red blood cells, platelets, white blood cells
function of red blood cells
transport oxygen
they contain a protein called hemoglobin that oxygen attaches to
platelets
cell fragments involved in blood clotting
white blood cells
defend the body against pathogens like bacteria and viruses
-mobile units of the bodys immune system
5 types of white blood cells
neutrophils eosinophils basophils monocytes lymphocytes
neutorphils, eosinophils, basophils, and monocytes are produced where
in bone marrow
lymphocytes are formed where
in organs of the lymphatic system (thymus and spleen
neutrophil function
phagocytosis
eosinophil function
kill parasites; play a role in allergies and asthma
basophil function
release histamine and other mediators of inflammation; contain heparin (an anticoagulant)
lymphocyte function
mount an immune response by direct cell attack or via antibodies
monocyte function
phagocytosis
hematocrit test
determines the percentage of erythrocytes in whole blood
hemoglobin determination test
measures how many grams of hemoglobin are in 100 ml of whole blood
