Blood in the heart chambers provides some nutrients to the heart muscle cells.
t
The myocardium receives its blood supply from the coronary arteries.
t
Anastomoses among coronary arterial branches provide collateral routes for blood delivery to the heart muscle.
t
The left side of the heart pumps the same volume of blood as the right.
t
Arterial blood supply to heart muscle is continuous whether the heart is in systole or diastole.
F
The papillary muscles contract after the other ventricular muscles so that they can take up the slack on the chordae tendineae before the full force of ventricular contractions sends blood against the AV valve flaps.
f
Auricles slightly increase blood volume in the ventricles.
f
Cardiac muscle has more mitochondria and depends less on a continual supply of oxygen than does skeletal muscle.
f
Congestive heart failure means that the pumping efficiency of the heart is depressed so that there is inadequate delivery of blood to body tissues.
t
Chronic release of excess thyroxine can cause a sustained increase in heart rate and a weakened heart.
t
The "lub" sounds of the heart are valuable in diagnosis because they provide information about the function of the heart's pulmonary and aortic valves.
f
Autonomic regulation of heart rate is via two reflex centers found in the pons.
f
An ECG provides direct information about valve function.
f
As pressure in the aorta rises due to atherosclerosis, more ventricular pressure is required to open the aortic valve.
t
Proxysmal atrial tachycardia is characterized by bursts of atrial contractions with little pause between them.
t
Tissues damaged by myocardial infarction are replaced by connective tissue.
t
Osmotic pressure is created by the presence in a fluid of small diffusible molecules that easily move through the capillary membrane.
f
The outermost layer of a blood vessel is the tunica intima.
f
Vasodilation is a widening of the lumen due to smooth muscle contraction.
f
The thick-walled arteries close to the heart are called muscular arteries.
f
A precapillary sphincter is a cuff of smooth muscle that regulates the flow of blood into the capillaries.
t
The pancreas is an example of an organ with arteries that do not anastomose.
f
Arteries supplying the same territory are often merged with one another, forming arterial anastomoses.
t
An increase in blood viscosity will cause an increase in peripheral resistance.
t
Hypotension is generally considered systolic blood pressure that is below 100 mm Hg.
t
The carotid sinus reflex protects the blood supply to the brain, whereas the aortic reflex is more concerned with maintaining adequate blood pressure in the systemic circuit as a whole.
t
The adjustment of blood flow to each tissue in proportion to its requirements at any point in time is termed autoregulation.
t
Every minute, about 1.5 ml of fluid leaks out of the capillaries.
t
Whereas diffusion is more important for solute exchange between plasma and interstitial fluid, bulk flow is more important for regulation of the relative volumes of blood and interstitial fluid.
t
Arterial pressure in the pulmonary circulation is much higher than in the systemic circulation because of its proximity to the heart.
f
The cerebral arterial circle (circle of Willis) is an arterial anastomosis.
t
The pulmonary circulation does not directly serve the metabolic needs of body tissues.
t
An obstruction in the superior vena cava would decrease the flow of blood from the head and neck to the heart.
t
The azygos vein originates in the abdomen.
t
Fetal hemoglobin has a higher affinity for oxygen than does adult hemoglobin.
t
The primary source of RBCs in the adult human being is the bone marrow in the shafts of the long bones.
f
Hemorrhagic anemias result from blood loss.
t
White blood cells are produced through the action of colony-stimulating factors.
t
Hemoglobin is made up of the protein heme and the red pigment globin.
f
Each hemoglobin molecule can transport two molecules of oxygen.
f
Diapedesis is the process by which red blood cells move into tissue spaces from the interior of blood capillaries.
f
Positive chemotaxis is a feedback system that signals leukocyte migration into damaged areas.
t
Basophils increase in number when parasitic invasion occurs.
f
Leukopenia is an abnormally low number of leukocytes.
t
Leukocytes move through the circulatory system by amoeboid motion.
f
Granulocytes called neutrophils are phagocytic and are the most numerous of all white blood cell types.
t
All lymphocytes are leukocytes, but not all leukocytes are lymphocytes.
t
Myelocytic leukemia involves a cancerous condition of lymphocytes.
f
Leukemia refers to cancerous conditions involving white blood cells.
t
The normal RBC "graveyard" is the liver.
f
Myeloid stem cells give rise to all leukocytes.
f
The immediate response to blood vessel injury is clotting.
f
The process of fibrinolysis disposes of bacteria when healing has occurred.
f
Clotting factor activation turns clotting factors into enzymes.
t
A person with type B blood could receive blood from a person with either type B or type O blood.
t