Why is it necessary for the dna to replicate prior to cell division?
a. so that each daughter cell will have 23 chromosomes
b. so that each daughter cell will have a complete copy of the genetic material
c. so that each daughter cell will have 46 homologous chromosomes
d. so that each daughter cell will have 2 sister chromatids

Aneuron is stimulated with an electric pulse. the action potential is detected at a point 3.70 cm down the axon 0.0052 s later.when the action potential is detected 7.20 cm from the point of stimulation, the time required is 0.0063 s. what is the speed of the electric pulse along the axon? (why are two measurements needed instead of only one? )

The phylogenetic tree illustrates the relationship between humans and our closest living relatives. the tree was based on biochemical comparisons, including dna and amino acid sequences. according to the biomolecular data, we could infer that

Why are scientists concerned about the depletion of the ozone levels in the stratosphere?