Question

how does the cell size of lactobacillus compare with that of anabaena?
cells of lactobacillus are about 2.5 times smaller than cells of anabaena.
cells of lactobacillus are about 5 times bigger than cells of anabaena.
cells of lactobacillus are about 10 times bigger than cells of anabaena.
cells of lactobacillus are about 25 times smaller than cells of anabaena.

Explanation:

Typically, the cells of Anabaena are larger than those of Lactobacillus. Lactobacillus cells are generally around 0.5 - 1.5 μm in diameter and 2 - 10 μm in length, while Anabaena cells can be several micrometers in diameter and up to tens of micrometers in length. Cells of Lactobacillus are about 2.5 times smaller than cells of Anabaena.

Answer:

Cells of Lactobacillus are about 2.5 times smaller than cells of Anabaena.