Alveoli
Alveoli
Cholesterol, blood clots, fat embolism', even plastic from a hypodermic needle that has broken off can block blood vessles.
When you have your period, the lining of your uterus sheds along with blood. This lining is made up of tissue and blood vessels that build up in the uterus each month in preparation for a potential pregnancy. When fertilization does not occur, this lining is shed during menstruation, resulting in a mixture of blood and tissue being released out of the body.
The tunica media is the middle layer of the wall of a blood vessel. It is made up of smooth muscle cells and sheets of elastic tissue that help regulate blood flow in the body by causing the blood vessel to narrow or widen.
The tunica interna of a blood vessel is a single layer of endothelium with a basal lamina.Connective tissue
The lining of the uterus is made up of endometrial tissue. This tissue contains glands, blood vessels, and a thick layer of cells that support and nourish a fertilized egg during pregnancy. Each month, the endometrial lining thickens in preparation for a potential pregnancy, and sheds if pregnancy does not occur during menstruation.
Blood is inside a blood vessel. Blood is made up of Red Blood Cells, White Blood cells, Platelets, and Plasma.
The tunica interna, is a thin layer only a few cells thick of a vein and artery, made up of connective tissue and elastic fibers. It is sometimes referred to as the intima membrane. It is this layer that gives smoothness to the lining of the vessel, enhancing blood flow.
Oxygen is picked up by the blood when it is at the lungs.
arteries
the vessel is made up of copper
The uterus creates a lining made up of blood and skin incase she becomes pregnant... if the egg is not fertilised then the girl doesn't need the lining so it comes out as a period until her next cycle and she rebuilds her lining... all to do with hormones ;)