SCIENCE - 1ST QT PRELIMINARY EXAMINATION

• What is another name for the circulatory system?

  Cardiovascular system
• What organs are included in the circulatory system?

  The heart, blood, and blood vessels
• What is the primary function of the circulatory system?

  To transport nutrients, gases, hormones, and other materials to and from body cells
• Besides transportation, what other function does the circulatory system serve?

  It functions in fighting infections
• What are the main components of the circulatory system?

  1. Heart
  2. Blood
  3. Blood Vessels
• What is the heart described as?

  The muscular pumping organ
• What role does the heart play in the circulatory system?

  It is the pumping blood station of the circulatory system
• What are the two main chambers of the heart?

  1. Atria
  2. Ventricles
• What is the function of the septum in the heart?

  It partitions the heart chambers
• What are the functions of the atria in the heart?

  • Receiving chambers of the heart
  • Right atrium receives oxygen-poor blood from the body
  • Left atrium receives oxygen-rich blood from the lungs
• What are the functions of the ventricles in the heart?

  • Pumping chambers of the heart
  • Right ventricle pumps oxygen-poor blood to the lungs for oxygenation
  • Left ventricle pumps oxygen-rich blood to all parts of the body
• What are the valves of the heart responsible for?

  Preventing blood from back flowing
• How do the valves of the heart function?

  They ensure that the blood will move only in one direction
• What are the two sets of valves in the heart?

  1. Atrioventricular Valves
  2. Semilunar Valves
• What are the atrioventricular valves in the heart?

  • Connect the atrium to the ventricles
  • Include the tricuspid valve and the mitral valve
• What are the semilunar valves in the heart?

  • Connect the heart ventricles to the arteries
  • Include the pulmonary valve and the aortic valve
• What type of circulatory system is described in the study material?

  Closed circulatory system
• Why is the circulatory system described as closed?

  Because blood circulates the whole body within the network of blood vessels
• What are the main functions of the human circulatory system?

  • Deliver blood to the organs
  • Deliver blood to the tissues in the body
• What are the three types of blood vessels?

  1. Arteries
  2. Veins
  3. Capillaries
• What is the primary function of arteries?

  To convey oxygen-rich blood away from the heart
• What is the exception regarding the type of blood transported by pulmonary arteries?


  They transport oxygen-poor blood
• What is the largest artery in the human body?

  Aorta
• What is the function of the aorta?

  To convey oxygen-rich blood pumped by the left ventricle to all parts of the body
• What are arterioles?

  The smallest arteries that regulate blood flow into the tissues and capillaries
• How do veins differ from arteries in terms of structure?

  Veins have thinner walls than arteries
• What type of blood do veins convey towards the heart?

  Oxygen-poor blood
• What are venules?

  The smallest veins that blood enters from capillaries
• What is the largest vein in the human body?

  Vena cava
• What is the structure and function of capillaries?

  • Location: Between venules and arterioles
  • Smallest and most numerous blood vessels
  • Main function: Exchange of materials (gases, nutrients, and waste products) between blood and tissue cells
• What is blood classified as in the human body?

  Blood is classified as a liquid tissue.
• What percentage of human body weight does blood comprise?


  Blood comprises 8% of human body weight.
• How much blood does an average adult have?

  An average adult has about five liters of blood.
• What are the main functions of blood?

  • Transports materials
  • Fights infections
• What is the liquid portion of blood called?

  The liquid portion of blood is called plasma.
• What are the formed elements of blood called?


  The formed elements of blood are called corpuscles.
• What percentage of blood by weight is plasma?

  Plasma comprises about 55% of the blood by weight.
• What is the composition of plasma?

  Plasma is composed mostly of water, blood proteins, and small amounts of inorganic materials.
• What percentage of blood by weight do corpuscles comprise?

  Corpuscles comprise 45% of the blood by weight.
• Where are corpuscles manufactured?

  Corpuscles are manufactured within the red bone marrow.