- Statement 1: Root hair cells are specialized epidermal cells of plant roots involved in water and nutrient absorption. They are eukaryotic cells and do contain a nucleus, cytoplasm, and other organelles. - Statement 2: Mature mammalian red blood cells (erythrocytes) are anucleated, meaning they lose their nucleus during maturation. This allows them to maximize the space available for hemoglobin, increasing oxygen-carrying capacity. - Statement 3: Platelets (thrombocytes) are not complete cells but are small, irregular fragments of cytoplasm derived from megakaryocytes found in bone marrow. They lack a nucleus. They play a crucial role in blood clotting. - Statement 4: Monocytes are a type of white blood cell (leukocyte) and are part of the immune system. They are large, mononuclear cells, meaning they do contain a prominent, often kidney-shaped or lobed nucleus. - Therefore, among the given options, only red blood cells and platelets lack a nucleus.