Red blood cells are not considered fully mature until they have lost their nucleus, ribosomes, and mitochondria. This may seem strange, and it is very odd for a cell not to have a nucleus, ribosomes, or mitochondria, but in the case of red blood cells, they don't really need them.fter all, red blood cells have to come from somewhere, and cells do need mitochondria and a nucleus with DNA to go through mitosis, make new cells, and make all of that hemoglobin protein. As it turns out, immature red blood cells do have mitochondria and a nucleus for just those reasons.
Definition of a Trapezoid. A trapezoid is a 2-dimensional geometric figure with four sides, at least one set of which are parallel. The parallel sides are called the bases, while the other sides are called the legs.
Confidence votes 2.7K. In geometry, a trapezoid, known as a trapezium outside of North America, is characterized by a convex quadrilateral with at least a single pair of parallel sides.However, some quadrilaterals with two pairs of parallel sides are simply known as parallelograms, and not considered a trapezoid at all.onfidence votes 2.7K. In geometry, a trapezoid, known as a trapezium outside of North America, is characterized by a convex quadrilateral with at least a single pair of parallel sides.