The key difference between vascular and avascular tissue is that the vascular tissue is the tissue with blood and lymphatic vessels such as veins, capillaries, and arteries while avascular tissue is the tissue that does not have blood and lymphatic vessels. Therefore, vascular tissues receive adequate blood supply but not the avascular tissues.
Vascular and vascular tissue are two types of tissues present in the human body. Most tissues in the human body have a good blood supply. Hence, they are vascular tissues. However, few avascular tissues are also present in the human body.
CONTENTS
1. Overview and Key Difference
2. What is a Vascular Tissue
3. What is an Avascular Tissue
4. Side by Side Comparison – Vascular vs Avascular Tissue in Tabular Form
5. Summary
What is a Vascular Tissue?
In human medicine, vascular tissue is a tissue having blood vessels and lymphatic vessels. These vessels carry blood and lymph throughout the body. Blood vessels such as arteries, veins, and capillaries transport gasses such as oxygen and carbon dioxide as well. Lymphatic vessels carry lymphatic fluid around the body.
Figure 01: Blood Vessels
Vascular tissues have an adequate of blood supply. Some tissues such as tissues of lungs and liver have a lot of blood vessels. Hence, they are known as highly vascularized tissues. Muscle tissue is another type of vascularized tissue.
What is an Avascular Tissue?
An avascular tissue is a tissue that does not have blood vessels and lymphatic vessels. Hence, this tissue does not receive a good blood supply. It always receives an inadequate supply of blood.
Figure 02: Eye
Cartilage, lens of the eye and epithelial layer of skin are some avascular tissues in human body. Some tissues normally do not consist of blood vessels since their function can be blocked by the presence of blood vessels. For example, blood vessels are not present in the lens since they can obscure the correct vision. Epithelial layer gets the nourishment via diffusion of substances through basement membrane since there are no blood vessels. But epithelial layer grows on vascular tissue. Tendons and ligaments also receive a poor blood supply.
What is the Difference Between Vascular and Avascular Tissue?
Vascular tissue consists of blood and lymphatic vessels. In contrast, avascular tissue does not contain blood and lymphatic vessels. Thus, vascular tissues consist of arteries, veins, capillaries and lymphatic vessels while avascular tissues do not. Moreover, vascular tissues have an adequate blood supply while avascular tissues do not receive sufficient blood supply. Muscle tissue, tissues of liver and lungs are some examples of vascular tissues. Cornea and lens of the eye, cartilage, epithelium of the skin, etc. are examples of avascular tissues. In fact, most tissues in the body are vascular.
Summary – Vascular vs Avascular Tissue
The difference between vascular and avascular tissue stems from the presence or absence of blood and lymphatic vessels. Some tissues are highly vascularized since they need an adequate blood supply for their functioning. Some tissues normally do not consist of blood vessels since their function can be blocked by the presence of blood vessels.
Reference:
1. Boumis, Robert. “Non-Vascular Vs. Vascular.” Sciencing, 21 Nov. 2017, Available here.
2. “Where Is Avascular Tissue Found in the Human Body.” QaAnswers, Answers Corporation, Available here.
Image Courtesy:
1. “Blood vessels-en” By Kelvinsong – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Schematic diagram of the human eye en” By Rhcastilhos. And Jmarchn. (CC BY-SA 3.0) via Commons Wikimedia