7.3.4 Blood Vessels and Circulation

• Arteries, veins, and capillaries are the three main types of blood vessels
• Arteries carry blood away from the heart under high pressure.
• Match the artery layer with its composition and function:

  Tunica Adventitia ↔️ Collagen and elastic fibers ||| Provides support and elasticity

  Tunica Media ↔️ Smooth muscle and elastic fibers ||| Controls vessel diameter

  Tunica Intima ↔️ Endothelial cells ||| Reduces friction
• What is the function of the tunica adventitia in arteries?

  Provides support and elasticity
• Veins carry blood back to the heart under lower pressure
• Veins have three layers similar to arteries, but with thinner walls.
• What structural adaptation in veins prevents backflow of blood?

  Valves
• Capillaries facilitate the exchange of substances between blood and tissues.
• What is the primary composition of capillaries?

  Single layer of endothelial cells
• Arteries have thick walls, a narrow lumen, and no valves
• Veins have wider lumens and present valves to prevent backflow.
• What is the main function of capillaries in blood circulation?

  Facilitate exchange of nutrients and waste
• Arrange the blood vessels in order of decreasing wall thickness.

  1️⃣ Arteries

  2️⃣ Veins

  3️⃣ Capillaries
• Arteries carry blood under high pressure
• Veins carry blood back to the heart under low pressure.
• What structural feature of capillaries allows for efficient substance exchange?

  Single layer of endothelial cells
• Veins return deoxygenated blood to the heart
• Match the blood vessel with its function in blood circulation:

  Arteries ↔️ Carry oxygenated blood away from the heart

  Veins ↔️ Return deoxygenated blood to the heart

  Capillaries ↔️ Facilitate exchange of nutrients and waste
• Why are capillaries essential for tissue function?

  Enable vital exchanges
• The tunica media in arteries contains smooth muscle that controls vessel diameter.
• The tunica intima in veins includes valves to prevent blood backflow
• What is the composition of the capillary wall?

  Single layer of endothelial cells
• Arrange the blood vessels in order of decreasing lumen size.

  1️⃣ Veins

  2️⃣ Arteries

  3️⃣ Capillaries
• Veins have valves, while arteries do not.
• What are the three main types of blood vessels in the cardiovascular system?

  Arteries, veins, capillaries
• Arteries carry blood away from the heart under high pressure
• Match the layer of an artery with its composition:

  Tunica Adventitia ↔️ Collagen and elastic fibers

  Tunica Media ↔️ Smooth muscle and elastic fibers

  Tunica Intima ↔️ Endothelial cells
• Veins carry blood to the heart under low pressure.
• The tunica intima of veins contains valves to prevent backflow
• What is the primary function of capillaries?

  Facilitate substance exchange
• Capillaries consist of a single layer of endothelial cells.
• Order the blood vessels from highest to lowest pressure:

  1️⃣ Arteries

  2️⃣ Veins

  3️⃣ Capillaries
• Arteries carry oxygenated blood away from the heart
• What type of blood do veins return to the heart?

  Deoxygenated blood
• Which blood vessels facilitate the exchange of nutrients and waste between blood and tissues?

  Capillaries
• Veins have thicker walls compared to arteries.

  False
• Why do arteries need thick, elastic walls?

  Withstand high pressure
• Veins have valves to prevent blood backflow
• Capillaries allow efficient diffusion due to their single-layered structure.
• Match the circulatory system with its pathway and key organs:

  Pulmonary Circulation ↔️ Heart → Lungs → Heart

  Systemic Circulation ↔️ Heart → Tissues → Heart