1.1d Cardiovascular and Respiratory Systems

• What are the two main circuits of the cardiovascular system?

  The systemic circuit and the pulmonary circuit
• What is the primary function of the systemic circuit?

  To transport oxygenated blood from the heart around the body and return deoxygenated blood back to the heart
• What does the pulmonary circuit do?

  It transports deoxygenated blood from the heart to the lungs and returns oxygenated blood back to the heart
• What are the three types of blood vessels in the vascular system?

  • Arteries
  • Capillaries
  • Veins
• What is the structure of arteries?

  They have a smooth muscle layer that can vasodilate and vasoconstrict to control blood flow
• What is the function of capillaries?

  To allow for gaseous exchange through a dense network around muscles and alveoli
• What is the structure of veins?

  They have a thin layer of smooth muscle and pocket valves to prevent backflow of blood
• How does the heart function as a double pump?

  The left side pumps oxygenated blood to the muscles and organs, while the right side pumps deoxygenated blood to the lungs
• What is oxygenated blood?

  Blood rich in oxygen and nutrients
• What is deoxygenated blood?


  Blood rich in carbon dioxide and waste products
• What is heart rate (HR)?

  The number of heart contractions each minute, measured in beats per minute (bpm)
• What is stroke volume (SV)?


  The volume of blood ejected from the left ventricle each beat, measured in millilitres (ml)
• What is cardiac output (Q)?

  The volume of blood ejected from the left ventricle each minute, measured in litres per minute (l/min)
• How do you calculate cardiac output?

  Cardiac output = heart rate (HR) x stroke volume (SV)
• What is the average resting heart rate?

  Around 72 bpm
• What is the role of the bicuspid, tricuspid, and semilunar valves?

  They prevent the backflow of blood through the heart
• What does the pulmonary artery do?

  It carries deoxygenated blood from the right ventricle to the lungs
• What does the pulmonary vein do?

  It carries oxygenated blood from the lungs to the left atrium
• What is the pathway of air through the respiratory system?

  Air enters through the nose and mouth, passes down the trachea, and into the bronchi and bronchioles, reaching the alveoli
• Where does gaseous exchange take place in the respiratory system?

  At the alveoli
• What is the structure of alveoli?


  They are composed of a single-cell-thick wall with a moist lining and are covered in capillaries
• What is diffusion in the context of respiration?

  The movement of gases from an area of high concentration to an area of low concentration
• What is the role of the diaphragm and intercostal muscles during inspiration?

  They contract to increase the volume of the chest cavity, decreasing pressure inside the lungs
• What happens during expiration?

  The diaphragm and intercostals relax, decreasing the chest cavity volume and pushing air out of the lungs
• What is breathing rate?

  The number of inspirations or expirations taken each minute
• What is tidal volume (TV)?

  The volume of air inspired or expired in one breath, measured in millilitres (ml)
• What is minute ventilation (MV)?

  The volume of air inspired or expired each minute, measured in litres per minute (l/min)
• How do you calculate minute ventilation?

  Minute ventilation = breathing frequency x tidal volume (TV)
• What is the difference between aerobic and anaerobic exercise?

  Aerobic exercise requires oxygen and can be sustained over time, while anaerobic exercise does not require oxygen and leads to fatigue
• What are the by-products of aerobic exercise?

  Carbon dioxide and water
• What are the by-products of anaerobic exercise?

  Lactic acid
• What are examples of aerobic and anaerobic exercises?

  Aerobic:

  • Jogging
  • Swimming
  • Cycling

  
  

  Anaerobic:

  • Sprinting
  • Weightlifting
  • High-intensity interval training (HIIT)
• What is lactic acid?


  The by-product of creating energy for the muscles without oxygen, which leads to pain and fatigue
• How does aerobic training affect red blood cells?

  Aerobic training increases the volume of red blood cells
• What is the role of haemoglobin in red blood cells?

  Haemoglobin is an iron-rich protein that transports oxygen in the bloodstream
• What is the average resting breathing rate?

  Around 12-15 breaths per minute
• What is the significance of the alveoli's structure for gas exchange?


  Their single-cell-thick walls and moist lining facilitate efficient gas exchange
• How do the roles of the diaphragm and intercostal muscles differ during inspiration and expiration?

  During inspiration, they contract to increase chest volume, while during expiration, they relax to decrease chest volume