Cardio vascula

• Blood


  The internal distribution of materials/substances

  
• Plants


  • They harness solar energy to transport water, minerals, and sugars through specialized tubes (xylem & phloem)
• Animals


  • A pump (heart) moves circulatory fluid (blood) through vessels
• The human body has the following organ systems: Nervous, Endocrine, Muscular, Skeletal, Integumentary, Circulatory, Immune
• Circulatory System


  Distributes water, nutrients, oxygen, hormones, and other substances throughout body and carries away carbon dioxide and other metabolic wastes; helps stabilize internal temperature and pH
• The circulatory system has a circulatory fluid (e.g., blood), a set of interconnecting vessels (i.e., arteries, veins & capillaries) and a muscular pump (i.e., heart)
• The circulatory system connects the fluid that surrounds cells (i.e., interstitial fluid) with the organs (e.g., lungs, intestines & kidneys) that exchange gases, absorb nutrients, and dispose of wastes
• Single-celled organisms (e.g., Amoeba)


  • Have sufficient surface area to carry out all necessary exchange
• Multicellular organisms with a saclike body plan (e.g., Hydra)


  • Have body walls that are only two cells thick, facilitating the diffusion of materials
• Salamander


  • Has external gills suitable for the short-range exchange of nutrients, wastes and gases (through diffusion) between blood and water
• Vertebrates have interstitial fluid (IF) that allows for the movement of material into and out of cells
• The lymphatic system normally reclaims fluid from interstitial fluid
• Cnidarians (e.g., moon jelly)

  • Have a gastrovascular cavity that functions in both digestion and distribution of substances throughout the body
• Flatworms


  • Have a gastrovascular cavity and a flat body that minimizes diffusion distances
• Open circulatory system


  Hemolymph (a circulatory fluid equivalent to blood) bathes the organs directly to enable the diffusion of nutrients (into) and wastes (out)
• Closed circulatory system


  Blood is confined to vessels and is distinct from the interstitial fluid

  
• Arteries


  • Carry blood away from the heart to the capillaries
• Capillaries


  • Sites of chemical exchange between the blood and interstitial fluid

  
• Veins


  • Return blood from capillaries to the heart
• Atria


  Blood is received into the atria
• Ventricles


  Blood is pushed out by the heart through the ventricles
• Ventricles don't pump, they contract and push blood. It's the heart that pumps
• Single circulation


  Blood leaving the two-chambered heart passes through two capillary beds before returning
• Double circulation


  Deoxygenated and oxygenated blood are pumped separately from the right and left sides of the heart
• Pulmonary circuit


  • The deoxygenated blood flows through this circuit to pick up oxygen through the lungs
• Systemic circuit


  • The oxygenated blood delivers oxygen through this circuit to body tissues
• Double circulation


  • Deoxygenated and oxygenated blood are pumped separately from the right and left sides of the heart
  • Double circulation maintains higher blood pressure in the organs than does single circulation
• Organisms with double circulation

  • Amphibians
  • Reptiles
  • Mammals
• Pulmonary circuit


  Deoxygenated blood flows through this circuit to pick up oxygen through the lungs
• Systemic circuit


  Oxygenated blood delivers oxygen through this circuit to body tissues
• Amphibians


  • Deoxygenated blood flows through a pulmocutaneous circuit to pick up oxygen through the lungs and skin
  • Oxygenated blood delivers oxygen through the systemic circuit
• Amphibians and many reptiles may pass long periods without gas exchange, or rely on gas exchange from another tissue, usually the skin
• Frogs


  • Ventricle pumps blood into a forked artery that splits the ventricle's output into the pulmocutaneous circuit and the systemic circuit
  • When underwater, blood flow to the lungs of frogs is nearly shut off, skin becomes a site for gaseous exchange
• Snakes


  • An incomplete septum divides the ventricles, but pulmonary and systemic circuits connect where arteries exit the heart
• Alligator (in water): Arterial valves temporarily shunt blood flow away from lungs
• Blood is a connective tissue consisting of several kinds of cells suspended in a liquid matrix called plasma

  
• Blood cellular elements


  • Platelets
  • White blood cells
  • Red blood cells

  
• Red blood cells


  Contain millions of haemoglobin, lack true nuclei & mitochondria, have large surface area, ATP generated anaerobically

  
• Red blood cell production is controlled by negative feedback
• Coagulation


  The formation of a solid clot from liquid blood