Which substance can enter a cell by diffusion without having to be digested

What do animals wth echolocation have in common other than echolocation

Amylase becomes denatured at a temperature of 80°c. during an experiment to study the effect of varyingtemperature on enzyme activity, amylase’s reactivity with starch was measured at body temperature (37°c), andthen again at an increased temperature of 42°c. how would this increase in temperature affect the experiment

Modern whales developed their traits through natural selection what occurs during the process of natural selection