The Structure and Function Of Arteries, Veins and Capillaries
In its route from the heart to the tissues, the blood passes through
channels of six foremost types: elastic arteries, muscular arteries,
arterioles, capillaries, venules and veins. I intend to explore the
structure and function of arteries, veins and capillaries. When an
artery branches into smaller and smaller vessels, eventually the blood
vessel is too small to see with the naked eye. At that point, it is
called an arteriole. Likewise, a venule is a microscopic vein.
Arteries
All arteries are comprised of three different layers but the
proportion and structure of each varies with the size and function of
the particular artery.
A large artery, like the aorta, is comprised of the following layers,
going from the inner to the most external layers:
(1) The innermost narrow layer consists of a layer of endothelial
cells separated from the inner layer by a thin layer of connective
tissue that anchors the cells to the wall.
(2) A large layer of elastic fibres forming the "elastica interna"
layer.
(3) Below this layer are concentric waves of muscle cells mixed with
elastic fibres.
(4) Between the smooth muscle layer and the outer layer, there is
again another layer of elastic fibres, the "elastica externa".
(5) The outer layer is formed of irregularly arranged strong collagen
bundles. These collagen bundles are extremely tough and ensure the
artery is strong enough to withstand high pressures of blood, without
bursting. Surrounding the outer layer are blood vessels that are
called "vasa vasorum" or vessels of the vessels.
This structure of ...
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...ction of the circulatory
system.
The structural differences between arteries and veins are all based in
their relationship to the heart. Since arteries receive blood from the
heart, the blood they receive is under a lot of pressure. At the same
time, this pressure helps the blood move through the arteries- even
when the arteries are opposing gravity (like the carotid artery
running towards the head).
In conclusion, the arteries carry oxygenated blood away from the
heart, and due to the high pressure of this blood the arteries have
thick wall, which contain many muscle fibres. The veins carry
deoxygenated blood to the heart and because blood is of a lower
pressure, have thinner walls consisting of less muscle fibres.
Capillaries are the principal part of the circulatory system; they
allow substance exchange.
I am now reporting to you from the patient’s femoral vein. I am headed north to her right lung. The femoral vein is one of the largest veins in the body. The ride has been smooth so far. I have been seeing many different types of cells go by my submarine window. I just saw an army of white blood cells headed the same way that I am. They most likely are headed towards the bacteria infestation in the right lung. I am also hearing the heart beat; it is making a LUB- DUB sound. I can also hear the blood flow; it is making sort of a swooshing noise. That noise is reminding me of the ocean! The right femoral vein is now turning into the external iliac vein; I am now by the urinary system and reproductive system. This is also known has the pelvic region. As we continue north the eternal iliac vein is now called the common iliac vein. As we continue on, the common iliac vein is now called the inferior vena cava. We are getting closer to the heart! We are in the abdomen of the body. There are diff...
The water was first poured on both hands, with fingers pointing upward, and must run through the arm as far as the wrist. It must drop off the wrist for the water is now unclean, having touched the
The cardiovascular system - The cardiovascular system is responsible for transporting nutrients and removing gaseous waste from the body. It consists of the heart, which powers the whole process, the veins, arteries, and capillaries, which deliver oxygen to tissue at the cellular level. The cardiovascular system carries blood that is low in oxygen away from the heart to the lungs via arteries, where oxygen levels are restored through the air once oxygenated, this blood is then carried throughout the body via arteries, keeping our organs and tissue alive. The cardiovascular system is the workhorse of the body, continuously moving to push blood to the cells. If this important system ceases its work, the body dies.
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Have you ever wondered how your eyes worked? How you see things? How colors appear to you? And what you actually aren’t seeing? There are many different ways our eyes work, and thankfully everyone’s eyes are different in their own way. Doctors today are still finding out new things about how our eyes work, and new ways to fix our eyes so we can see better, or even fix little in corrections our eyes make. Have you ever looked at an object in front of you and still were able to see more objects around it, but not clearly? Those inconveniences are called blind spots. Many people are unaware about blind spots in their eyes, or what colors their eyes are actually seeing. A blind spot is a gap in your vision that causes you to see things out of the corner of your eyes, or see everything at once that can sometimes occur blurry to some people. Most of everyone has a blind spot in their eyes, and don’t even notice it. This anatomy review considers whether you have blind spots in your eyes, and how well you notice things with your eyes. I will answer the following questions:
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How we came to know what we know now about anatomy and physiology has always been a great curiosity of anyone interested in the medical field. Knowing the history can lead to even more discoveries in the future. When you think of anatomy you imagine something like this picture below.