7.3.4 Blood Vessels and Circulation

• What are the three main types of blood vessels that form the cardiovascular system?

  Arteries, veins, capillaries
• Arteries carry blood away from the heart
• The tunica adventitia of arteries is made of collagen and elastic fibers.
• What is the function of the tunica intima in arteries?

  Reduce friction
• Veins carry blood back to the heart under lower pressure
• What do the valves in veins prevent?

  Backflow of blood
• Capillaries consist of a single layer of endothelial cells.
• Match the blood vessel type with its characteristic feature:

  Arteries ↔️ Thick walls

  Veins ↔️ Present valves

  Capillaries ↔️ Very narrow lumen
• Veins have thinner walls and wider lumen
• Which layer of veins contains valves?

  Tunica intima
• Capillaries facilitate the exchange of substances between blood and tissues.
• Arteries have higher blood pressure
• What type of blood do arteries carry away from the heart?

  Oxygenated blood
• What do veins return to the heart?

  Deoxygenated blood
• What is the primary function of capillaries in blood circulation?

  Exchange of nutrients and waste
• Arrange the following features from highest to lowest in terms of blood pressure:

  1️⃣ Arteries

  2️⃣ Veins

  3️⃣ Capillaries
• The outermost layer of a vein is called the tunica adventitia
• What prevents backflow of blood in veins?

  Valves
• Capillaries are the smallest blood vessels, facilitating exchange between blood and tissues
• The single layer of cells in capillaries is called the endothelial layer
• Which type of blood vessel has the thickest wall?

  Arteries
• Veins have a wider lumen compared to arteries.
• Veins are the only blood vessels with valves
• What is the function of the tunica media in arteries?

  Controls vessel diameter
• The tunica intima in arteries reduces friction with its smooth lining.
• What type of blood do arteries carry away from the heart?

  Oxygenated
• Veins return deoxygenated blood to the heart.
• Match the blood vessel with its function:

  Arteries ↔️ Carry oxygenated blood away from the heart

  Veins ↔️ Return deoxygenated blood to the heart

  Capillaries ↔️ Facilitate exchange between blood and tissues
• Which blood vessels carry oxygenated blood away from the heart?

  Arteries
• Veins return deoxygenated blood to the heart.
• Capillaries facilitate the exchange of nutrients and waste between blood and tissues.
• Match the blood vessel with its structural adaptation:

  Arteries ↔️ Thick walls with elastic fibers

  Veins ↔️ Valves to prevent backflow

  Capillaries ↔️ Single layer of endothelial cells
• Arteries withstand high pressure due to their thick walls and elastic fibers.
• Veins have valves to ensure blood flows in one direction.
• What structural feature allows capillaries to facilitate efficient exchange of substances?

  Single endothelial layer
• In the pulmonary system, blood flows from the right ventricle to the pulmonary artery.
• What is the primary role of the pulmonary circulatory system?

  Oxygenation of blood
• Trace the pathway of blood through the pulmonary circulatory system.

  1️⃣ Right ventricle

  2️⃣ Pulmonary artery

  3️⃣ Lungs

  4️⃣ Pulmonary veins

  5️⃣ Left atrium
• Oxygenated blood in the pulmonary circulatory system returns to the left atrium via the pulmonary veins
• What is the primary role of the systemic circulatory system?

  Deliver oxygen to tissues