MT2 Chap 17 - Blood and Blood vessels Flashcards
overall goal of the system is
to transport O2 and nutrients to tissues of body, and remove CO2 and metabolic wastes from body
Arteries
move blood away from heart
Veins
move blood to heart
Capillaries
allow for transport of gases and nutrients into and out of the blood
Function of Cardiovascular System
- Transports
- Regulates pH and ions [ ]
- Restriction of fluid loss
- Defence against toxins and pathogens
- Stabilization of body temp
Total fluid is what % of body weight
60%
- 40% of intracellular fluid: fluid inside cells
- 20% extracellular fluid: fluid outside cells
- —80% Interstitial fluid: water surrounding cells
- —20% plasma: water in blood stream
55% of blood is
plasma
blood plasma contains and doesn’t contain ….
- Contains: dissolved protein (involved in transport and clotting), dissolved gases, electrolytes and organic nutrients.
- Does not contain: collagen and elastin
Leukocytes = WBCs involved in
immune response
Albumin
60% of plasma protein
-transporting lipid
Globulins
- 35% of plasma proteins
- includes antibodies and transport globulins produced in the liver
Antibodies
-specialized proteins involved in immunity
Fibrinogen and Prothrombin
- 4% of plasma protein
- produced in liver
- involved in blood clotting
Lipoproteins
- produced in liver
- involved in transporting triglycerides and cholesterol
Hormones and enzymes
specialized functions
Source of most plasma proteins
liver
Small amounts of ____ & ___ are dissolved in blood
oxygen and CO2
What plays a more important role in gas transport?
RBC and bicarbonate
Monosaccharides, amino acids, a water soluble vitamins are ….
nutrients
lactate breaks down products from
glucose
urea breaks down products from
protein
uric acid breaks down products from
DNA/ RNA
Creatinine breaks down products from
Creatine phosphate
Bilirubin breaks down products from
hemoglobin
Hematocrit
% by volume of blood that is formed elements
- Male 46%
- Female 42%
Erythrocytes
Structure :
- no nucleus
- full of hemoglobin
Erythrocyte production requires
folic acid and vitamin b12
Erythrocytes function:
transport O2 and CO2
Erythrocytes significance of shape
- large SA
- form stacks
- Bend and flex
Neutrophils
most abundant phagocyte in blood
Eosinophils
destroy parasitic worms
Basophils
release histamine and heparin
Lymphocytes
- involved in antibody production
- WBCs
- HAVE nucleus
- function: defense
Monocytes
can leave blood stream and differentiate into Macrophages
platelets
- Anuclear (w/o nucleus)
- involved in blood clotting
- formed from larger Megakaryocytes
- 2/3 circulating
- 1/3 in spleen
All blood cells are formed in ___ from a common blood stem cell, ____
bone marrow,
hemocytoblast
Hemopoiesis
formed elements of blood develop
Rate of erythropoiesis is measured by
the # of immature RBCs in the peripheral circulation
reticulocytes or retics
immature RBCs
normal range is 1-2% of RBCs being
retics
what % of blood is RBCs
45%
During differentiation RBCs synthesize large amounts of the protein ____. Once hemoglobin production is complete, the RBCs ___ ___ ___ and organelles
Hemoglobin
eject their nucleus
once differentiated, RBC cannot
replicate, synthesize protein or produce ATP
Anemia is a condition of
insufficient RBCs or hemoglobin
Polycythemia is a condition of
excess number of RBCs
Hemorrhagic Anemia is the result of
precipitous blood loss
RBC production is controlled by
O2 saturation in blood
RBC production requires
Fe, Protein, vitamins B12 and folic acid
WBC location
- Most: in connective tissue or organs in lymphoid system (thymus, spleen, lymph nodes)
- Small portion: circulate blood stream
What differentiates the 2 groups of WBC?
whether they contain conspicuous chemical-filled cytoplasmic granules (when stained)
WBC type: Granulocytes
include neutrophils, eosinophils, and basophils
WBC type: Agranulocytes
are the monocytes and lymphocytes
Special properties of circulating WBCs
- Diapedesis: process of squeezing out of capillaries and entering tissue
- Amoeboid movement
- Positive chemotaxis
- Phagocytosis
Chemicals released by microbes and inflamed tissues attract phagocytes, a phenomenon called
chemotaxis
3 stages to hemostasis
- vascular spasms
- Platelet Plug formation
- Coagulation
Vascular Spasm phase
minimize blood loss while next steps take place
Platelet phase
- platelets stick to endothelial cells and exposed collagen fibres
- becomes a plug and releases chemical messengers
Coagulation
blood clotting
2 stages of recovery
- Clot retraction
2. Fibrinolysis
Clot retraction
- occurs once platelets and RBCs entangled in fibrin mesh
- platelets contract by pulling torn edges of vessel closer together, reducing the size of damaged area
Fibrinolysis
- as repairs take place, clot dissolves
- as enzyme plasmin digests fibrin
Systemic Circulation
- supplies tissues with nutrient and oxygen-rich blood
- begins in left ventricle and pumped out of aorta
- Deoxygenated blood returns to right atrium via superior and inferior vena cava
Pulmonary Circulation
- Deoxygenated blood pumped by right ventricle through pulmonary arteries to capillaries in lungs where its oxygenated
- Oxygenated blood returns to left atrium through pulmonary veins
Cardiac Perfusion
- heart receives its own blood through coronary arteries, which branch off aorta
- heart only receives blood during relaxation
3 layer of blood vessels (3 tunics)
- Tunica Intima (only in arteries)
- Tunica Media
- Tunica Externa
Tunica Intima
- one layer of endothelial cells
- reduces friction btwn the vessel walls and blood
Tunica Media
- made of smooth muscle and elastic tissue
- controls vasoconstriction and vasodilation
Tunica Externa
- composed of collagen
- protects, reinforces and anchors the vessel
Elastic arteries
- largest arteries
- aorta and pulmonary trunk
- transports large volumes
Muscular Arteries
-carries blood to skeletal muscle and organs
Arterioles
-branch within organs
Function of Arterioles
- control local distribution of blood to capillary beds
- Help regulate BP
Capillaries
- consists of endothelial tube inside a delicate basal lamina
- 2 way exchange
Vasomotion
constriction/ dilation of precapillary sphincter
Factors influencing flow through veins
- low pressure in right atria
- gravity
- Sympathetic Input
- “Muscular Pump”
- Respiratory pump