Understanding Blood Vessel Anatomy

Describe the three tunics common to most vessels and explain their general functions.

• Tunica intima, tunica media, tunica externa; they provide structural support, regulate blood flow, and protect the vessel.

• Tunica externa, tunica media, tunica interna; they are responsible for nutrient exchange, blood filtration, and waste removal.

• Tunica intima, tunica media, tunica externa; they facilitate blood flow, provide elasticity, and offer protection.

• Tunica interna, tunica media, tunica externa; they control blood pressure, regulate temperature, and transport hormones.

Compare and contrast the composition of elastic arteries, muscular arteries, and arterioles.

• Elastic arteries have more smooth muscle, muscular arteries have more elastic fibers, and arterioles have a thick tunica externa.

• Elastic arteries have more elastic fibers, muscular arteries have more smooth muscle, and arterioles have a thin tunica media.

• Elastic arteries have a thin tunica media, muscular arteries have a thick tunica externa, and arterioles have more elastic fibers.

• Elastic arteries have a thick tunica externa, muscular arteries have more elastic fibers, and arterioles have more smooth muscle.

Describe the general anatomic structure and function of capillaries.

• Capillaries have a single layer of endothelial cells and facilitate nutrient and gas exchange.

• Capillaries have multiple layers of smooth muscle and regulate blood pressure.

• Capillaries have a thick tunica externa and provide structural support.

• Capillaries have a thick tunica media and control blood flow velocity.

Compare the anatomic structure, function, and location of continuous capillaries, fenestrated capillaries, and sinusoids.

• Continuous capillaries have large pores, fenestrated capillaries have tight junctions, and sinusoids are found in the brain.

• Continuous capillaries have tight junctions, fenestrated capillaries have small pores, and sinusoids have large gaps and are found in the liver.

• Continuous capillaries have small pores, fenestrated capillaries have large gaps, and sinusoids have tight junctions and are found in the kidneys.

• Continuous capillaries have large gaps, fenestrated capillaries have tight junctions, and sinusoids are found in the intestines.

Explain the process of diffusion and vesicular transport between capillaries and tissues.

• Diffusion involves the movement of large molecules through vesicles, while vesicular transport involves the passive movement of gases.

• Diffusion involves the passive movement of small molecules and gases, while vesicular transport involves the active transport of larger molecules via vesicles.

• Diffusion involves the active transport of ions, while vesicular transport involves the passive movement of nutrients.

• Diffusion involves the movement of water, while vesicular transport involves the movement of gases.

Compare and contrast hydrostatic pressure and colloid osmotic pressure in capillaries.

• Hydrostatic pressure pushes fluid into capillaries, while colloid osmotic pressure pulls fluid out of capillaries.

• Hydrostatic pressure pulls fluid out of capillaries, while colloid osmotic pressure pushes fluid into capillaries.

• Hydrostatic pressure pushes fluid out of capillaries, while colloid osmotic pressure pulls fluid into capillaries.

• Hydrostatic pressure and colloid osmotic pressure both push fluid into capillaries.

Explain the lymphatic system’s role at the capillary bed.

• The lymphatic system absorbs excess fluid and proteins from the interstitial space and returns them to the bloodstream.

• The lymphatic system filters blood directly from the capillaries and removes waste products.

• The lymphatic system provides oxygen to tissues and removes carbon dioxide from the bloodstream.

• The lymphatic system regulates blood pressure by constricting and dilating capillaries.

Describe the myogenic response that maintains normal blood flow through a tissue.

• The myogenic response involves the dilation of blood vessels in response to increased blood pressure.

• The myogenic response involves the constriction of blood vessels in response to decreased blood pressure.

• The myogenic response involves the constriction of blood vessels in response to increased blood pressure and dilation in response to decreased blood pressure.

• The myogenic response involves the dilation of blood vessels in response to decreased blood pressure and constriction in response to increased blood pressure.

Explain how a tissue auto-regulates local blood flow based on metabolic needs.

• Tissues increase blood flow by releasing vasoconstrictors in response to high oxygen levels.

• Tissues decrease blood flow by releasing vasodilators in response to low carbon dioxide levels.

• Tissues increase blood flow by releasing vasodilators in response to low oxygen and high carbon dioxide levels.

• Tissues decrease blood flow by releasing vasoconstrictors in response to high carbon dioxide levels.

Describe features of the pulmonary circulation that distinguish it from systemic circulation.

• Pulmonary circulation has higher pressure and carries oxygenated blood to the lungs.

• Pulmonary circulation has lower pressure and carries deoxygenated blood to the lungs.

• Pulmonary circulation has higher pressure and carries deoxygenated blood to the heart.

• Pulmonary circulation has lower pressure and carries oxygenated blood to the heart.