Compared to those of humans, the erythrocytes in frog are

1. Without nucleus but with haemoglobin
2. nucleated and with haemoglobin
3. very much smaller and fewer
4. nucleated and without haemoglobin.

The erythrocytes or RBCs in frog are large, oval and biconvex nucleated cells with respiratory red pigment haemoglobin in its cytoplasm.