Describe the appearance and behaviour of chromosomes during prophase and during anaphase of mitosis.
Write down the formula used to calculate the mitotic index of a tissue sample observed under a light microscope.
A biologist investigated the effect of varying concentrations of cadmium ions (Cd2+\text{Cd}^{2+}Cd2+) on cell division in the root meristem of broad bean plants (Vicia faba). The biologist calculated a Spearman's rank correlation coefficient (rsr_srs) between the concentration of cadmium ions and the mitotic index of the root cells.
The calculation yielded rs=−0.79r_s = -0.79rs=−0.79 with a probability of P<0.05P < 0.05P<0.05.
What can you conclude from this result?