Week 7 - Lecture 3 - Blood Vessels KPU Courses

What are the three layers of an artery's structure?

Tunica interna, tunica media, tunica externa.

What is the innermost layer of an artery called?

Tunica interna.

What type of epithelium is the endothelium made of?

Simple squamous epithelium.

What does the basement membrane provide to the artery?

Tensile strength and physical support.

What is the function of the internal elastic lamina in arteries?

Allows elasticity and has pores for nutrient diffusion.

What is the primary composition of the tunica media in elastic arteries?

Elastic fibers.

What do we call the contraction of smooth muscle in blood vessels?

Vasoconstriction.

What do we call the relaxation of smooth muscle in blood vessels?

Vasodilation.

What are muscular arteries primarily composed of?

Smooth muscle.

What is an anastomosis?

A connection between two arteries providing multiple routes of circulation.

What do arterioles regulate?

Blood flow into the capillaries.

What is the terminal segment of arterioles called?

Metaarterioles.

What are the first venous structures after capillaries?

Postcapillary venules.

What type of blood vessel has valves to prevent backflow?

Veins.

What is the primary function of capillaries?

Exchange of nutrients and waste.

What type of capillary is the least leaky?

Continuous capillaries.

Where are fenestrated capillaries commonly found?

In the kidneys and small intestine.

What is the purpose of the fenestrations in fenestrated capillaries?

To facilitate faster movement of materials.

What do sinusoid capillaries allow for that other capillaries do not?

Movement of larger molecules or cells.

What percentage of blood is commonly found in veins when at rest?

Over 60 percent.

What term refers to the pooling of blood in veins when at rest?

Blood reservoir.

What happens to blood flow during exercise?

Veins undergo venoconstriction to divert blood to tissues.

What are the key components of the tunica externa?

Collagen and elastic fibers.

Which arteries are described as conducting arteries?

Elastic arteries.

What type of arteries branch off to supply blood to various organs?

Muscular arteries.

What are the two primary functions of the tunica media?

Control lumen diameter and regulate blood flow.

What layer is absent in veins compared to arteries?

Elastic lamina.

How does the structure of veins contribute to blood flow?

Thinner walls and larger lumens allow for lower pressure.

What do postcapillary venules and capillaries have in common?

Both are very leaky and allow for exchange with interstitial fluid.

What is the primary role of the external elastic lamina?

Provides elasticity and allows diffusion in muscular arteries.