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

Evolutionary Biology-Genetic Drift, Imagine a population evolving by geneti...

Imagine a population evolving by genetic drift in which the frequency of allele K is 0.65. What is the probability that at some point in the future allele K will drift to a frequen

Phylum placozoa, Phylum Placozoa The phylum Placozoa contains a single...

Phylum Placozoa The phylum Placozoa contains a single species of a minute marine animal Trichoplax adharens composed of a dorsal and ventral epithelial layer enclosing loose m

Mechanical valves, Mechanical Valves They are made of a combination o...

Mechanical Valves They are made of a combination of metal alloys, pyrolite carbon and dacron. Types of Mechanical Valves Caged-ball Valve (Star-Edwards) A me

What are mycotoxins and how are they harmful, Q. What are mycotoxins and Ho...

Q. What are mycotoxins and How are they harmful? • Mycotoxins are toxins (secondary metabolites) produced by filamentous fungi on food and feed that cause illness when ingested

How many carbon dioxide molecules liberated in krebs cycle, Q. How many car...

Q. How many carbon dioxide (CO 2 ) molecules are liberated after each cycle of the Krebs cycle? For a single glucose how many carbon dioxide molecules were already liberated by the

Coronal disassembly devices-grasping instruments, Grasping instruments ...

Grasping instruments -Plier or clamp forceps -put piece of rubber in the plier                                 -applied on the buccal and lingual surface -make pressure to

How are solutions classified, Q. How are solutions classified as per to the...

Q. How are solutions classified as per to their comparative tonicity? Comparative to another, a solution can be isotonic or isosmotic, hypotonic or hyposmotic or hypertonic or

Explain ganongs potometer, For measuring the rate of transpiration of a twi...

For measuring the rate of transpiration of a twig using Ganong's potometer, learner A cuts the twig and fits it in the broad end of the water-filled potometer. Learner B cuts the t

Male reproductive disorders-testicular hypoplasia, Testicular Hypoplasia ...

Testicular Hypoplasia Hypoplasia refers to testicular disorders related to congenitally underdeveloped and underactive spermatic epithelium of one or both testes even though t

Explain neurosyphilis, Neurosyphilis  Symptomatic neurosyphilis, includ...

Neurosyphilis  Symptomatic neurosyphilis, including ophthalmic or otic infection, requires treatment with high doses of aqueous penicillin G IV or procaine penicillin G IM with

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