The Anatomy Of The Artery

Explanation
Atherosclerosis is a slowly progressive disease of muscular arteries where the inner layer thickens due to the accumulation of fatty deposits and fibrous tissue. This condition leads to the narrowing and hardening of the arteries, reducing blood flow and increasing the risk of various cardiovascular complications such as heart attack and stroke.

Explanation
The correct answer is "Intima" because it refers to the innermost layer of the artery that is composed of a thin layer of endothelial cells. These cells are in direct contact with the blood flowing through the artery.

Explanation
The correct answer is "Media". The media is the middle and thickest layer of the artery composed of smooth muscle cells. These smooth muscle cells have the ability to constrict and dilate the vessel wall, which helps in regulating blood flow.

Explanation
The correct answer is Adventitia because it is the outer layer of the artery that contains fibroblasts, collagen, blood vessels, nerves, and lymphatics which all service the vessel. The adventitia provides structural support to the artery and helps maintain its shape and integrity. It also plays a role in regulating blood flow and immune response in the vessel.

Explanation
The correct answer is Lumen. The lumen refers to the opening within an artery that provides a channel for blood flow. It is the space through which blood flows, allowing it to circulate throughout the body. The lumen is important for maintaining proper blood flow and ensuring that oxygen and nutrients are delivered to the tissues and organs.

Explanation
Foam cells are a type of cell that accumulate in the subendothelial layer of blood vessels. These cells are filled with lipids, giving them a foamy appearance. When examined under a microscope, they appear as a "fatty streak." Foam cells are a key component of early atherosclerotic lesions and play a role in the development of atherosclerosis. They are formed when macrophages engulf oxidized low-density lipoproteins (LDL) and become filled with cholesterol and other lipids. The accumulation of foam cells contributes to the formation of fibrous plaques, which can lead to the narrowing and hardening of blood vessels.

Explanation
The correct answer is Endothelial cells. Endothelial cells line the inner surface of blood vessels and provide a protective barrier against thrombotic substances like cholesterol. However, when these cells are injured, they lose their protective barrier and become exposed. This exposure attracts monocytes and smooth muscle cells, which can contribute to the formation of blood clots and plaque buildup in the arteries.

Explanation
Smooth muscle cells are responsible for movement and contraction of myofibrils within the cell. They also play a role in the synthesis of collagen, elastin, and other components that form the structure of the media layer in the artery. These cells provide receptors for LDL and platelet-derived growth factor (PDGF) during the synthesis state, allowing these molecules to migrate from the media layer to the intima layer.

Explanation
Platelets contain numerous biochemical "bombs" that are released into the bloodstream upon impact. These biochemicals attract more platelets, smooth muscle cell proliferation, and ADP & epinephrine, which induce vasoconstriction and increase the pressure gradient within the artery. Therefore, platelets play a crucial role in blood clotting or sticking together.

Explanation
The explanation for the correct answer is that the response to injury hypothesis suggests that the initial step in the development of atherosclerosis is the injury to the intima layer of the blood vessel. This injury can be caused by various factors such as hypertension (HTN) and smoking. Once the intima layer is injured, circulating monocytes enter the subendothelial space and transform into macrophages. This triggers the initiation of atherogenesis, which is the formation of fatty plaques in the blood vessel walls. Therefore, the correct answer is "Response to injury hypothesis."