Which substance is considered a building block for all living things?

The population of bacteria in a petri dish doubles every 40 seconds. the population of the bacteria is initially 400 organisms. what unit is most appropriate for the time at which the number of bacteria is 300? hour bacteria per hour second bacteria per second

Imagine that a mouse has white fur because of a mutation in its dna. which of the following conclusions can be drawn

What is the ecological role of food chains and food webs