Which classification describes RBCs of standard size?

Red blood cells are classified by size, and the term normocytic refers to red blood cells of standard or normal size, with a mean corpuscular volume (MCV) in the reference range of approximately 80–100 femtoliters. This classification is used in the differential diagnosis of anemia. Normocytic anemia — where cells are normal in size but reduced in number — is seen in conditions such as acute blood loss, anemia of chronic disease, or hemolytic anemia. Microcytic refers to abnormally small red blood cells with an MCV below 80 fL, typically caused by iron deficiency, thalassemia, or lead poisoning. Macrocytic refers to abnormally large red blood cells with an MCV above 100 fL, associated with folate or vitamin B12 deficiency. Anisocytic describes red blood cells that vary abnormally in size, with a mix of small and large cells, and is quantified by the red cell distribution width (RDW). Students should memorize these terms as they guide the clinical workup of anemia — understanding the MCV helps narrow the etiology and directs appropriate laboratory follow-up such as iron studies, B12, or peripheral blood smear evaluation.