Ch 44 Internal Transport Flashcards
• Combination of the Cardiovascular and
Immune/Lymphatic systems plus associated organs
Vertebrate Circulatory System
Vertebrate Circulatory System functions have diversified extensively
– Transports: nutrients, oxygen, wastes, hormones
– Helps maintain fluid balance, pH, temperature
– Defends against microrganisms
- Intercellular matrix of blood
- Water and salts
- Substances in transport
Plasma
– fibrinogen
• for blood clotting
– some are antibodies
Plasma Protein
- Transport oxygen; help with CO2 transport
* Contain hemoglobin
Red Blood Cells (Erythrocytes)
– red pigment that binds with oxygen
– some invertebrates have free
hemoglobin-like pigment without red blood cells (earthworms)
– others have different transport pigments (& no rbc ’s)
• hemocyanin in some mollusks is blue
Hemoglobin
Defend body against disease organisms – semi-independent, amoeboid cells – Examples • Neutrophils • Lymphocytes
White Blood Cells (Leukocytes)
60% of WBCs
– perform phagocytosis
Neutrophils
25-35% of WBCs
– make antibodies
– destroy foreign cells
-with chemicals
Lymphocytes
Platelets
– Patch damaged blood vessels
– Release substances essential for blood clotting
Blood clotting
Fragments of cells with membrane, no nucleus
Platelets
Carry blood away from heart
Arteries
Return blood to the heart
Veins
What in blood vessels cause:
– constriction
– dilation
Smooth muscles
– directly connect arterioles and venules
Metarterioles
Branch off metarterioles
– thin-walled exchange vessels
– allow materials to transfer between blood and tissues
Capillaries
Blood flows from arteries to veins via metarterioles and capillaries.
Smooth muscle sphincters control which capillaries receive blood.
Plasma may move from capillaries to interstial fluid. Fluid is returned to veins through lymphatic vessels.
Blood Vessels
• Specialized cardiac muscles move blood
• Valves prevent backflow of blood
• Sinoatrial (SA) node (pacemaker)
– initiates each heartbeat
• Specialized muscle cells conduct action potential throughout heart
– coordinates beats
The Human Heart
Connects heart and lungs
• Right ventricle ➡️ pulmonary arteries ➡️ lungs (pulmonary capillaries)➡️pulmonary vein ➡️left atrium
Pulmonary circulation
Connects heart and tissues
• Left ventricle ➡️aorta ➡️arteries ➡️body organs (capillary networks)➡️veins➡️superior or inferior vena cava➡️returns to right atrium
Systemic circulation
Are far from the heart and have low blood pressure.
Veins
Blood flow in veins is maintained through:
- low resistance
- one way valves
- body movement
- nearby skeletal muscles help move blood
• Important in fluid balance • Defends body against disease – phagocytes filter out bacteria • Absorbs lipids • Collects interstitial fluid, returns it to blood
Lymphatic System
Clear fluid formed from interstitial fluid
Lymph