Flashcards in Circulatory and Respiratory Systems Deck (58):
Describe flow of blood from heart to body.
-Aorta --> arteries --> arterioles --> capillaries (diffusion) --> venules --> veins ---> heart
What blood does the right side of the heart carry?
-Deoxygenated blood to pulmonary circulation
Left side of the heart...
...carries oxygenated blood to systemic circulation.
Are atria or ventricles thin walled?
Which ventricle is more muscular?
Left ventricle --> generates enough force to pump blood against higher resistance
Detail the path of blood returning to heart.
-Into right atrium --> tricuspid valve --> right ventricle --> pulmonary semilunar valve --> pulmonary arteries --> lungs --> pulmonary veins --> left atrium --> mitral valve --> left ventricle --> aortic semilunar valve --> systemic
Which valves have two cusps? Three?
-2: mitral valve
-3: tricuspid and semilunar valves
-Cardiac muscle relaxation
-Blood drains into all 4 chambers`
Heartbeat is made up by
-Systole and Diastole
Cardiac output is calculated by
heart rate (bpm) x stroke volume (blood volume pumped out of left ventricle/contraction)
Cardiac contractions regulated by
-Sinoatrial node (SA) - pacemaker
Where is the SA located?
-Wall of right atrium
What is the difference between the superior and inferior vena cava?
-Superior brings deoxygenated blood from upper half of body to right atrium
-Inferior from the bottom half
How does the SA regulate heart rate?
-Both atria contract --> AV node --> ventricles fill with blood
-Impulse carried by bundle of His (AV bundle) --> Purkinje fibers in both ventricles --> contraction
How does epinephrine regulate heart rate?
-Secreted by adrenal medulla
List blood vessel type by increasing thickness.
What drives blood flow in veins?
-Contraction of skeletal muscles during movement
Why do veins have valves?
-Prevent backflow as venous circulation often opposed gravity
-Single layer of epithelial cells
-Transport excess interstitial fluid (lymph) to cardiovascular system
-Keep fluid levels in body constant
-Collect fats (chylomicrons) from villi in small intestine --> bloodstream
-Smallest lymph vessels
Swellings along lymph vessels with phagocytic cells (lymphocytes) that filter lymph
What are the cellular components of blood?
Erythrocytes, leukocytes, platelets
What is plasma made up of?
-Liquid portion of blood
-Nutrients, salts, gases, wastes, hormones, blood proteins (immunoglobulins, albumin, fibrinogen)
Why do RBC have a biconcave disk shape?
-Gives more flexibility and greater SA
Where are RBC formed?
-Bone marrow, stimulated by erythropoietin
-In bone marrow, lose nuclei, mitochondria, membranous organelles --> blood
What type of antigen does type A blood have? Antibodies?
-Type A antigen
-Type B anitbody
What does erythroblastosis fetalis result from?
-Rh- mother pregnant with Rh+ baby first then pregnant again with Rh+ baby (now has anti-Rh antibodies)
Where are amino acids and simple sugars absorbed into the bloodstream?
Describe the clotting cascade.
-Exposed collagen cause platelets to form plug.
-Platelets and tissue release thromboplastin.
-Thromboplastin converts prothrombin to thrombin.
-Thrombin converts fibrinogen to fibrin.
-Fibrin traps blood cells --> clot
What are methods of anticoagulants?
-Inhibit recycling of vitamin K (needed as cofactor of thromboplastin)
What is the path air follows in respiratory tract?
-External intercostal muscles contract
-Rib cage/chest wall pushed up and out
-Fill with air
-Lungs/chest recoil to original position
-Pressure increase, air forced out of alveoli
-Protein complex secreted by cells in lungs
-Decreases surface tension in alveoli
-Prevents lung collapse
What part of the brain controls ventilation?
Would increasing the partial pressure of CO2 in blood increase or decrease ventilation?
Increase to maintain proper concentrations of oxygen, carbon dioxide, and hydrogen ions
What surrounds alveoli?
Pulmonary capillaries (minute blood vessels)
Total lung capacity
-Max volume of air lungs can hold
-Volume air moved during normal resting breath which differs from max by the inspiratory/expiratory reserve volume
-Volume of air moved in max inhalation/exhalation
What is the primary cause of movement of lymph?
-Pressure of skeletal muscles
Is the pressure of lymph in vessels high or low?
-Low so the difference can draw liquid from tissues into lymphatic system
How is liquid returned to blood?
-Lymph vessels that drain into large veins of cardiovascular system
Where do the lymphatic and circulatory systems meet?
Blockage of the thoracic duct would inhibit absorption of...
Is the partial pressure of oxygen higher or lower in alveoli than pulmonary capillaries (blood)?
-Higher--> flows down pressure gradient and binds to hemoglobin
Is the partial pressure of carbon dioxide higher or lower in alveoli than pulmonary capillaries (blood)?
-Lower --> flows into alveoli for expiration
Trapped particulate matter in respiratory system is moved towards what part of tract for expulsion?
What are the two membranes of the lungs?
-Visceral and parietal pleura with interpleural space in between
What is the purpose of the pressure differential between interpleural space and lungs?
-Keeps lungs inflated
What kind of breathing is inhalation?
-Negative pressure breathing (air enters lungs due to vacuum created)
What compresses the lungs during exhalation?
-Internal intercostal muscles opposed to contraction of external intercostal muscles in inhalation
Can exhalation be a passive process?
-Yes, during strenuous activitis