Question

How blood reaches our tissues? If its from our veins than wouldn't that be considered as an internal bleeding because the vein needs to be open to transport blood. Explain your answer in detail.

Answer 1

As the heart beats, it pumps blood through a system of blood vessels, called the circulatory system. The vessels are elastic tubes that carry blood to every part of the body.
There are three main types of blood vessels
Arteries
1. Arteries begin with the aorta, the large artery leaving the heart.
2. They carry oxygen-rich blood away from the heart to all of the body's tissues.
3. They branch several times, becoming smaller and smaller as they carry blood further from the heart.
Capillaries
1. Capillaries are small, thin blood vessels that connect the arteries and the veins.
2. Their thin walls allow oxygen, nutrients, carbon dioxide and waste products to pass to and from the tissue cells.
Veins
1. These are blood vessels that take oxygen-poor blood back to the heart.
2. Veins become larger and larger as they get closer to the heart.
3. The superior vena cava is the large vein that brings blood from the head and arms to the heart, and the inferior vena cava brings blood from the abdomen and legs into the heart.