Question

multiple choice question
describe the shape of a red blood cell.
columnar
biconcave disc
cuboidal
squamousal
spherical

Explanation:

Red blood cells are known for their unique biconcave disc - shaped structure which increases their surface area for gas exchange. Columnar, cuboidal, squamous are shapes related to epithelial cells, and spherical is not the shape of red - blood cells.

Answer:

B. Biconcave disc