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Blood Vessels

The channels that convey blood throughout the body are known as blood vessels. They form a closed loop, similar to a circuit, that begins and ends at your heart. Your heart vessels and blood vessels work together to form your circulatory system. In your body, there are roughly 60,000 kilometres of blood veins.

Introduction

Blood vessels are responsible for delivering blood to your body’s organs and tissues. They get the oxygen and nutrients they require from the bloodstream. Waste products and CO2 are also carried away from your organs and tissues by blood vessels.
Although blood arteries resemble tubes, they rarely run in a straight line. Some of them are large enough to see through your skin. You may have observed veins on the inside of your arm if you’ve ever had your blood drawn. Even if your blood is red, they may seem blue under your skin.

The tissue of blood arteries is divided into three layers

  • The inner layer of the Tunica intima surrounds the blood as it circulates through your body. It keeps toxins out of your blood, maintains blood pressure, and avoids blood clots. It maintains a healthy blood flow
  • Elastic fibres in the intermediate layer keep your blood flowing in a single path. The media also aids in the expansion and contraction of arteries
  • Nerves and small veins are found in the outer layer of adventitia. It helps remove waste and transports oxygen and nutrients from your blood to your cells. It also gives blood vessels structure and stability

Types of Blood Vessels

There are three types of blood vessels: – 

Arteries

  • These muscular blood vessels transport oxygen-rich blood from your heart to the rest of your body. They can withstand a lot of strain and pressure from your blood flow, but they can’t carry much blood. Only around 10% to 15% of your body’s blood flows through your arteries at any given moment
    Arteries are blood vessels that carry oxygenated blood from the heart to the rest of the body. They’re tough on the surface, but they feature a smooth layer of epithelial cells on the inside that allows blood to flow easily. In arteries, there is a strong, muscular middle layer that aids in the pumping of blood throughout the body
  • Arteries branch into arterioles, which are smaller vessels. Arterioles and arteries are both extremely flexible. They grow or shrink in size to help keep your blood pressure in check
    The arteries (red) deliver oxygen and nutrients from your heart to your body’s tissues. The veins (blue) are in charge of returning exhausted oxygenated blood to the heart. The aorta, the main artery leaving the guts, is where arteries begin.
  • They are liable for transporting oxygen-rich blood from the guts to all or any of the body’s tissues. As they carry blood far away from the guts , they branch multiple times and become smaller and smaller

    Capillaries

  • Capillaries have thin walls and are tiny blood vessels. The blood’s oxygen and nutrients can pass through the walls and into the organs and tissues. Waste materials are also removed away from your tissues by capillaries. Oxygen and nutrients are exchanged for carbon dioxide and waste in capillaries.
    Small, thin blood vessels that connect the arteries and veins are referred to as capillaries. The tissue cells’ thin walls allow oxygen, nutrients, carbon dioxide, and waste materials to undergo
  • The arteries and veins are connected by capillaries. The arteries transport oxygen-rich blood to the capillaries, where the oxygen and carbon dioxide are exchanged. The waste-rich blood is subsequently delivered to the veins, where it is transported back to the lungs and heart

Veins

  • Unlike arteries, veins do not have to transport highly pressured blood, but they must transport enormous volumes of deoxygenated blood back to your heart. They can manage huge volumes and low pressure thanks to their thin, less elastic walls. The valves in most veins open and close. Blood flow is controlled by valves, which keep blood flowing in one direction. Your veins contain about 75% of your blood
  • The blood is returned to the guts via veins. They resemble arteries, although they are not as powerful or thick. Veins, unlike arteries, have valves that ensure blood only travels in a method. (Arteries don’t need valves since the heart’s pressure is so high that blood can only flow in a method.) Valves also assist blood in returning to the guts against gravity
  • Venules: Veins start off as small veins called venules and get larger as they move closer to your heart. Capillaries supply blood to venules. These are blood vessels that take oxygen-poor blood back to the guts. Veins become larger and bigger as they meet up with to the guts. The superior vein is the large vein that brings blood from the top and arms to the guts, and therefore the inferior vein brings blood from the abdomen and legs into the heart
  • The vast system of blood vessels including arteries, veins, and capillaries is over 60,000 miles long which is long enough to travel round the world quite twice.
    Blood flows continuously through your body’s blood vessels. Your heart is the pump that creates it all possible

Conclusion

Blood carries nutrition, oxygen, and water to cells throughout the body via the cardiovascular system. Although the voyage begins and ends with the heart, blood arteries connect every critical organ along the road. A large network of pipes is formed by these arteries, veins, and capillaries.

The function and structure of blood arteries in humans can be influenced by a variety of diseases and disorders. Inflammation, atherosclerosis (fat deposition in the artery endothelium), and hypertension (an excessive increase in blood pressure caused by narrowing of the arterioles) are only a few examples. The terms artery, capillary, vein, and cardiovascular disease are all used interchangeably.