Arteries - circulation, Biology

Assignment Help:

Arteries - Circulation

The arteries deliver blood from the heart. Figure shows the structure of arteries and the different layers of the vessel wall. The thick walls of these blood vessels, except those of the smallest, are supplied by their own capillary network called vasa vasoram. The arteries serve four main functions:

  1. To act as a conduit for blood between heart and capillaries,
  2. To act as a pressure reservoir for forcing blood into small diameter arterioles,
  3. To produce a more or less even flow of blood through the capillaries,
  4. To control distribution of blood to different capillary networks via selective constriction of the terminal branches

 

 

143_Arteries - Circulation.png

Figure: Major structures in peripheral blood circulation in mammals. Blood flows from the arteries through the capillaries into the veins (id is internal diameter).

There is a precise control on arterial blood pressure. The nature of the arterial wall and the volume of blood pumped into the arteries determine the pressure. If any of these are changed, the pressure will also change. Normally, arterial blood pressure varies very little as cardiac output and capillary flow is evenly matched.

The elastic properties of arterial walls vary. Close to the heart the arteries are elastic and dampen the oscillations in pressure and flow generated by the contractions of the heart. As the heart relaxes the pressure in the arteries is maintained by a reduction in vessel volume. If the arteries were rigid tubes then the same pressure fluctuations would be experienced by peripheral vessels as that observed when blood leaves the heart.


Related Discussions:- Arteries - circulation

Digestive system - mouth, MOUT H - It is as transverse slit. It is ...

MOUT H - It is as transverse slit. It is pseudo type i.e. not open directly into alimentary canal. Mouth is covered by upper & lower movable lips. Movement is due to arb

What is phellogen, What is phellogen? What is its function? Phellogen, ...

What is phellogen? What is its function? Phellogen, also called as cork cambium, is the meristematic plant tissue responsible for the formation of the periderm (the covering of

How are triglycerides made, How are triglycerides made? Triglycerides, ...

How are triglycerides made? Triglycerides, fats or oils, are made of three molecules of fatty acids bound to single molecule of glycerol. Hydroxyls of each one of the three fat

Local needs, Local Needs, Choices and Circumstances Beyond obvious cho...

Local Needs, Choices and Circumstances Beyond obvious choice for private sector, the best public-private balance for a country depends on its local culture and circumstances.

Chromosomes with spindle fiber, Chromosomes with spindle fiber: The kineto...

Chromosomes with spindle fiber: The kinetochore fibers of spindle attach to the kinetochore region (specialized area in centromere) of chromosome, and align them at the equator of

Explain the flexibility exercises and its examples, Flexibility Exercises a...

Flexibility Exercises and Examples In  flexibility exercises, movable joints allow one or more of the following types of movements. Flexion - Flexion decreases the joint ang

What is the function of the flagellum of the sperm cell, What is the functi...

What is the function of the flagellum of the sperm cell? How is it formed? The flagellum of the sperm cell is produced by the centrioles that migrate to the region posterior to

Plasma proteins - circulation, Plasma Proteins - Circulation The total...

Plasma Proteins - Circulation The total protein concentration of the plasma is around 7% only. The plasma proteins are of three types - serum albumin (4%), serum globulin (2.7

Structural features of viruses, Structural Features of Viruses Size of...

Structural Features of Viruses Size of Viruses Virus particles vary widely in size. The smallest viruses e.g. virus of foot and mouth disease  measuring about 20  mill mic

Characteristics of lake ecosystems, Characteristics of Lake Ecosystems ...

Characteristics of Lake Ecosystems The environment of static waters of lakes and ponds sharply contrasts with those of lotic ecosystems. Light penetration in lakes is usually

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd