Circulatory and Respiratory systems Flashcards
Blood is pumped away from the heart via
the Aorta
Where does gas exchange occur between the blood and tissues?
capillaries
What carries the blood back to the heart?
Veins
What side of the heart pumps deoxygenated blood into the pulmonary circulation?
right side
What side of the heart pumps oxygenated blood into the systemic circulation
left side
Which is more muscular, the atria or the ventricles?
the ventricles
Which ventricle is more muscular?
left
What can can lead to congestice heart failure and other cardiovascular diseases?
hypertrophied heart (enlarged) due to systemic resistance
Describe the flow of blood through the heart
superior vena cava - right atrium - tricuspid vavle - right ventricle - pulmonary semilunar valve - pulmonary arteris - lungs - plumonary veins - left atrium - mitral valve - left ventricle - aortic semilunar valve - rest of body
atrioventricular valves
located between the atria and ventricles on both sides of the heart. prevent backflow of blood into the atria
tricuspid valve
atrioventricular valve on the right side. 3 cusps
Mitral valve
atrioventriculr valve on the left side of the heart. 2 cusps.
semilunar valve
3 cusps. located between the left ventricle and the aorta (the aortic valve) and between the right ventricle and the pulmonary artery (pulmonic valve)
“lub-dub” sound
made by successive vlosing of the atrioventriular and semilunar valves
what makes up the heartbeat?
systole and diastole
systole
ventricles contract, forcing blood out of the heart into the pulmonary and systemic circulation
Diastole
cardiac muscle relaxation. blood drains from all four chambers
cardiac output
total volume of blood the left ventricle pumps out per minute. Cardiac output= heart rate X Stroke Volume
cardiac muscle
contracts rhythmically without stimulation from the nervous system
SA node
where cardiac contraction originates. the pacemaker. in the wall of the RA
AV node
impulse from SA node arrives here. it slowly conducts impulses to the rest of the heart, allowing enough time for atrial contraction and for the ventricles to fill with blood.
Bundle of His (AV bundle)
impulse from AV node sent here. Branches into the left and right bundle branches.
Purkinje Fibers
impulse goes here from the Bundle of His. It is in the walls of both ventricles, stimulating a strong contraction that forces the blood out of the heart and in to circulation.
What modifies the rate of heart contraction?
autonomic nervous system
What effect does the parasympathetic nervous system have on the heart?
innervates it with the vagus nerve and causes a decrease in heart rate
What effect does the sympathetic nervous system have on the heart?
innervates it with the cervical and upper thoracic ganglia and causes an increase in heart rate.
What effect does the adrenal medulla have on the heart rate?
exerts hormonal control via epinephrine secretion, which causes increased heart rate.
Arteries
Thick walled, muscular, elastic. transports blood away from the heart
Pulmonary Artery
The only artery that carries deoxygenated blood. Carried it from the heart to the lungs.
Veins
thin walled, inelastic, carry blood to the heart. Movement of blood through veins is more dependent on muscle movement. Depends on gravity too. Have valves that prevent back flow
Pulmonary Vein
The only vein that carries oxygenated blood. from the lungs to the heart.
capillaries
Composed of a single layer of endothelial cells across which respiratory gases, nutrients, enzymes, hormones, and wastes can readily diffuse. smallest diameter of blood vessels
Lymphatic system
secondary circulation system. vessels transport interstitial fluid called lymph, keeping fluid levels in the blood constant.
lacteals
the smallest lymphatic vessels that collect fat in the form of chylomicrons from the vili in small intestines and transfer them to the blood stream, bypassing the liver.
Lymph Nodes
swellings along lymph vessels containing phagocytic cells (lymphocytes)
How much blood does the human body normal contain?
4-6 liters
What percentage of the two components is blood made up?
55% liquid components, 45% cellular components.
Plasma
Liquid portion of blood. 55%. aqueous mixture of nutrients, salt, respiratory gases, wastes, hormones, and blood proteins
Cellular components of blood
45%. erythrocytes, leukocytes, and platelets
leukocytes
white blood cells. larger than erythrocytes and serve protective functions.
platelets
cell fragments that lack nuclei and are involved in clot formation. Many drugs inhibit clot formation or adhesion to decrease clot development
erythrocytes
RBC. oxygen carrying components of blood. 250 million molecules of hemoglobin, which can bind up to four O molecules. distinct biconcave, disk like shape that gives them both increased surface area for gas exchange and greater flexibility for movement through tiny capillaries. Formed from cells in bone marrow.
oxyhemoglobin
when hemoglobin binds to O. The primary form of oxygen transport in the blood.
What is erythrocyte formation stimulated by?
erythropoetin, a hormone made in the kidneys
How are erythrocytes made?
erythropoietin (hormone from kidneys) stimulate production in bone marrow. Here the erythrocytes lose their nuclei, mitochondria and membranous organelles.
How long to mature erythrocytes circulate in blood?
120 days. they are then phagocyticed by specialized cells in the spleen and liver.
Hemolytic anemia
can be detected by finding immature erythrocytes in blood stream.
antigens
cell-surface proteins. Macromolecules that are foreign to the host organism and trigger an immune response.
Two major groups of blood cell antigens
ABO group and Rh factor
Universal blood acceptor
AB
Universal donor
O
Rh Factor
Can be + or -. particularly important during pregnancy.
reythroblastosis fetalis
Rh - mother has first pregnancy with Rh + baby who sensitizes her to it. For second pregnancy with Rh+ baby, the anti-Rh antibodies she produces from the first pregnancy can attack the fetal blood cells across the placenta. Drug used to help Rh- mothers is Rogham.
Drug used to help rH mothers
Rogham
Clotting cascade
When exposed to collagen of damaged vessel, thromboplastin, with the aid of calcium and vit K, turn prothrombin (inactive) into thrombin (active.) Thrombin then converts fibrinogen into fibrin, which coats the damaged area and traps blood cells to form clot. Fluid left after clotting is called serum
Warfarin
anticoagulant that inhibits the recycling of vitamin K in the clotting cascade.
What does the air passage consist of
nose, pharynx (throat), larynx, trachea, bronchi, bronchioles, and alveoli
Where does gas exchange occur in respiratory system?
across the very thin walls of the alveoli
alveoli
larger surface area for gas exchange
What else is the respiratory system good for?
moving oxygenated air across the surfaces and protecting from dehydration, infection, and temperature change. Helps the vocal chords with sound and to balance pH in body.
ventilation
air inhaled and exhaled. Take in O from atmosphere and eliminate CO2 from body
inhalation
diaphragm contracts and flattens, external intercostal muscles contract, pushing rib cage and chest wall up and out. phrenic nerve innervates diaphragm. These actions cause the thoracic cavity to increase volume, which reduces the pressure, causing lungs to expand and fill with air
exhalation
passive. lungs and chest recoil to their original position after inhalation. relax and chest wall pushes inward. decrease in thoracic cavity volume causes the pressure to go up, forcing air out.
surfactant
protein complex secreted by cells in the lungs. keeps lungs from collapsing by decreasing surface tension in the alveoli. Premies need artificial surfactant
What part of the brain controls respiration?
medulla oblongata. When pressure of CO2 rises, it stimulates an increase in the rate of ventilation,
What are the primary stimulation for respiration?
excessive CO2 levels and H levels in blood
total lung capacity
max volume of air the lungs can hold
tidal volume
volume of air moved during a normal resting breath
inspiratory reserve volume
the amount of air that could be forced in after the tidal volume
expiratory reserve
the volume of air left in the lungs at the end of tidal volume.
Vital capacity
the volume of air moved during a maximal inhalation followed by max exhalation.
residual volume
the volume of air left in the lungs after vital capacity
