• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Arteries are adapted to their function in blood transport from the heart.

Extracts from this document...

Introduction

Arteries are adapted to their function in blood transport from the heart Arteries are tubular vessels that carry blood from the heart to the rest of the body. Arteries have a very thick lining; the outer lining is made from collagen fibres and elastic tissue. This is there because it helps the arteries expand under the high pressure that the blood is forced out from the heart. The second layer is made from thick smooth muscle. This is there so when the arteries expand the muscle can contract when this happens it pushes the blood along the vessel in a smooth regular fashion. This is called a pulse. The arteries do not need valves; this is because the blood is being pumped at such a high pressure and the fact that the muscle contracts to stop the blood going back along the artery. The inner lining is made from epithelium cells. These are there to ensure that the blood can run smoothly along the vessel without resistance. The blood travels through many arteries. ...read more.

Middle

The veins are made from the same materials as the arteries but are different in terms of thickness. The muscle around the veins is very thin this is because the blood is not at a high pressure. Because of the low pressure the blood has not got a pulse unlike the arteries, which do. They also have a larger lumen then the arteries to let more blood through. When the blood flows through the arteries the arteries split up into arterioles these then divide again into capillaries. They take blood to all of the tissues in the body. The capillaries are very small. They are also very thin vessels. They are made of one cell thick endothelium. These vessels link up the arteries with the veins. When the blood enters the capillaries it slows down, this takes away most of the pressure and allows for exchange of chemicals to take place more efficiently. The slowing down of the blood also results in the capillaries having no pulse or valves. The capillaries are so small that the lumen is only big enough for one red blood cell to squeeze through. ...read more.

Conclusion

Arteries have to undertake the pressures of the blood being pumped from the heart at 93mmHg. They are special in the way that they have thick muscle walls and are very elastic. If they were not elastic then the blood cannot be pushed though them at high pressures and the pulse would not happen. They are different from the veins in many ways; they do not have valves, they do not have thin muscular walls, blood is passed through the veins at low pressure this does not happen in the arteries, also veins have a large lumen whereas the arteries do not. They differ a lot from the capillaries too; capillaries are one cell thick obviously the arteries are not, the capillaries have no pulse, and a very small lumen a lot smaller than the arteries. The arteries, the veins and the capillaries all have different roles to play in the transport of blood around our bodies. They have been designed for these different roles, the arteries take blood away from the heart, the capillaries ensure that chemicals can be exchanged and the veins take the blood back to heart. This is all done in balance and is regulated by the heart and brain. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Humans as Organisms section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Humans as Organisms essays

  1. Marked by a teacher

    Explain how arteries, veins, and capillaries are adapted for their functions. Describe what happens ...

    4 star(s)

    This protrudes into the lumen and starts to obstruct the blood flow. During increased physical activity, a narrowed artery restricts the oxygen supply to the myocardium resulting in angina pectoris. This is normally felt as pain in the chest or left arm or shoulder and is usually the first indication of CHD.

  2. The Structure and Function Of Arteries, Veins and Capillaries.

    Skeletal muscles surround the veins; and contract to squeeze blood along the veins. Venous valves keep blood moving in only one direction. Venous valves are formed from the endothelium (vein lining), in places where the endothelial cells bend into the lumen of the vein.

  1. Stem Cell Research

    drugs' effects without harming living organisms, to make sure that they are suitable for humans to use. This means that less trialling of drugs would be carried out on humans and animals. For example, steroids can be tested for their various effects on the muscle cells (which are cultured from stem cells).

  2. Blood - moving around our bodies via the circulatory system, consisting of the arteries, ...

    The amount of lymphocytes rapidly proliferates when faced with infection and there are two fundamental types of this kind of agranulocyte: the B-lymphocytes and the T-lymphocytes. Both sorts recognise surface markers on cells and target them for destruction if foreign to the body, however, B-lymphocytes have a tendency to transfer

  1. Investigating the density of blood

    I will allow the blood droplet to reach its average speed before starting to measure the time at the 100cm mark. 6. Once the blood reaches the 10cm mark I will record the time taken to travel the distance between the two marks.

  2. The cardiovascular system is made up of the heart and the blood vessels, such ...

    Leukocytes, or white cells Leukocytes, or white cells, are responsible for the defence of the organism. In the blood, they are much less numerous than red cells. Lymphocytes are a major part of the immune system. Other white cells called granulocytes and macrophages protect our body from infection by surrounding and engulfing the infection.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work