circulatory systems

• What are the different types of circulatory system?

  open

  closed

  single

  double
• What is an open circulatory system?

  a system where blood can diffuse out of vessels e.g insects
• What is a closed circulatory system?

  A closed circulatory system is a type of circulatory system in which blood is contained within vessels and does not directly come into contact with body tissues.

  :blood confined to vessels e.g mammals and fish
• What is a single circulatory system?

  blood passes through pump once per circuit of the body
• What is a double circulatory system?

  A circulatory system in which blood passes through the heart twice in one complete circuit of the body.
• What type of circulatory system do fish have?

  fish have a single circulatory system:

  the heart pumps blood to the gills (to pick up oxygen) and then on through the rest of the body (to deliver the oxygen) in a single circuit
• What type of circulatory system do mammals have?

  mammals have a closed double circulatory system

  the right side of the heart pumps blood to the lungs to pick up oxygen

  from the lungs the blood travels to the left side of the heart, which pumps it to the rest of the body

  when blood returns to the heart, it enters the right side again
• What is the pulmonary system?


  the circuit that sends blood to the lungs
• What is the systemic system?


  the circuit that sends blood to the rest of the body
• What type of circulatory system do some invertebrates have?

  an open circulatory system- blood isn't enclosed in blood vessels all the time, instead it flows freely through the body cavity

  1. the heart is segmented, it contracts in a wave, starting from the back, pumping the blood into a single main artery
  2. that artery opens up into the body cavity
  3. the blood flows around the insect's organs, gradually making its way back into the heart segments through a series of valves
• What is the function of the circulatory system in insects?

  to supply the insect's cells with nutrients, and transport hormones and other substances around the body

  it doesn't supply the insect's with oxygen though- this is done by the tracheal system
• what is an open circulatory system?


  a circulatory system in which the organism's blood is free to flow throughout the body cavity

  open circulatory systems are found in insects
• what is closed circulatory system?


  a circulatory system in which the blood is restricted to flowing through blood vessels

  the heart (a pump) is required to get blood to all parts of the body
• who has a closed circulatory system?


  fish have single closed circulatory systems

  mammals have double closed circulatory systems
• why are fish said to have a single circulatory system?


  as the blood only travels through the heart ONCE in every circuit around the body
• why are mammals said to have a double circulatory system?


  as the blood travels through the HEART TWICE per circuit
• what is better about double circulatory systems than single ?


  double circulatory systems are more efficient (faster) in transporting oxygenated blood to tissues e.g muscles than single circulatory systems

  the concentration gradient between the blood and cells is better maintained in double circulatory systems, so substances are exchanged between the blood and body cells faster
• what are the 2 better things about double circ than single circ?

  1. More efficient at transporting oxygenated blood to tissues
  2. Better maintained concentration gradient between blood and cells, so faster exchange of substances
• what happens in a double circulatory system?


  blood flows through the heart twice per circuit

  deoxygenated blood is pumped to the lungs

  oxygenated blood is pumped around the body