Final answer:
The tissue type with polarity and that is avascular is epithelial tissue .It covers body surfaces and cavities, with nutrients supplied via diffusion from connective tissues.
Step-by-step explanation:
The tissue type that has polarity and is avascular is epithelium.
Epithelial tissue, also known as epithelium, is characterized by cells that are closely packed together, forming a protective layer that covers the body surfaces, lines internal cavities, and forms glands. This type of tissue is defined by its polarity, having an apical surface that faces the exterior of the body or an internal space, and a basal surface where it is attached to underlying connective tissue. Importantly, epithelial tissue lacks blood vessels, meaning it is avascular. Nutrients are rather supplied to epithelial cells by diffusion through the underlying connective tissues. The polarity and avascular nature of epithelial tissues are key in allowing it to act as a selective barrier, regulating the exchange of materials between the body and the external environment or between different body compartments.
Epithelial tissue, also referred to as epithelium, refers to the sheets of cells that cover exterior surfaces of the body, line internal cavities and passageways, and form certain glands. It is characterized by its polarity, meaning it has distinct apical and basal surfaces. Epithelial tissue is also avascular, meaning it does not contain blood vessels. It obtains nutrients and oxygen through diffusion from nearby blood vessels in the underlying connective tissue.