L4-Respiratory and Circulatory

• Respiration


  The process of taking up oxygen and expelling carbon dioxide, also known as gas exchange
• Respiratory System


  • A set of structures and/or organs coordinated to take up oxygen and expel carbon dioxide
  • Only animals have a set of organs dedicated to this function

  
• Gas exchange


  The process of oxygen availability to animals depending on the external respiratory medium and environmental factors such as temperature, salinity, altitude, and distance from air interference

  
• Breathing


  The physical process of intake of fresh air and removal of foul air

  
• Respiration


  The biochemical process of oxidation of food to form carbon dioxide, water and energy
• Respiratory gases


  • Oxygen (O2)
  • Carbon Dioxide (CO2)

  
• Cellular respiration


  Intracellular catabolic reactions that convert stored energy to ATP

  
• External respiration


  The physiological process that transports O2 into and CO2 out of the body (between environment and lungs)
• Internal respiration


  The physiological process that transports O2 into and CO2 out of cells (between blood and cells)
• Ventilation


  The bulk flow of air or water to and from the respiratory membrane during the act of breathing

  
• Types of ventilation


  • Passive (environmental medium moves over the respiratory membrane via currents)
  • Active (animal uses metabolic energy to bring the environmental medium to the respiratory membrane)
  • Unidirectional (air or water is pumped over the membrane in a one-way path)
  • Bidirectional (tidal) (air or water alternately flows to and from membrane via same passages)
  • Nondirectional (air or water flows across gas-exchange membrane in many directions)
• Types of respiratory systems

  • Cutaneous (skin or body surface)
  • Branchial (book gills and gills)
  • Tracheal (trachea and air tubes)
  • Pulmonary (book lungs, pulmonary sacs, and true lungs)

  
• Complex animals adapted to terrestrial life have lungs which are localized respiratory organs that are not in contact with other parts of the body, but are bridged by the cardiovascular system which transports gases between the lungs and the rest of the body

  
• Respiratory system


  Takes in oxygen and sends out carbon dioxide, an exchange known as respiration

  
• Parts of the respiratory system

  • Airways (trachea, bronchi, bronchioles, alveoli)
  • Lungs (elastic tissue, pleura, thorax, diaphragm)

  
• Oxygen transport


  1. Oxygen moves from alveoli to blood through capillaries by diffusion

  2. Oxygen picked up by hemoglobin in red blood cells

  3. Oxygen-rich blood pumped by heart to body

  
• Carbon dioxide transport


  1. Carbon dioxide moves from cells into capillaries and bloodstream

  2. Blood rich in carbon dioxide travels to heart and then lungs

  3. Carbon dioxide moves from capillaries around alveoli into alveoli and is exhaled

  
• Heart


  A muscular organ that pumps blood throughout the body, delivering oxygen, hormones, glucose and other components

  
• Heart


  • Has two upper chambers (atria) and two lower chambers (ventricles)
  • Atria have relatively thin walls and collect blood
  • Ventricles have thicker walls and pump blood

  
• Parts of the heart

  • Inferior vena cava
  • Superior vena cava
  • Right atrium
  • Left atrium
  • Right ventricle
  • Left ventricle
  • Pulmonary artery
  • Pulmonary vein
  • Aorta

  
• Heart valves


  Prevent the backflow of blood

  
• Types of heart valves

  • Atrioventricular valves (tricuspid, mitral)
  • Semilunar valves (aortic, pulmonary)

  
• Blood vessels


  • Arteries (thick walled, carry blood away from heart)
  • Veins (thin walled, carry blood to heart)
  • Capillaries (tiny vessels involved in gas and nutrient exchange)

  
• Blood


  Consists of various cells and proteins that facilitate body functioning
• Blood cells


  Made in the bone marrow, help replace cells that die naturally or through injury/illness
• Plasma


  Made up mostly of water, also contains proteins, fatty substances, salt, nutrients, vitamins and hormones
• Types of blood circulation

  • Pulmonary circulation (carries deoxygenated blood from right heart to lungs and back to left heart)
  • Systemic circulation (carries oxygenated blood from heart to body and back)

  
• The heart is a pump that beats about 60-100 times per minute, sending blood throughout the body to deliver oxygen to cells

  
• The circulatory system is made up of blood vessels that carry blood away from and towards the heart, delivering oxygen, nutrients, and hormones to cells and removing waste products