Addition of pyrophosphate to which of the following occurs during the first step of purine biosynthesis? question 8 options: 5-phosphoribosyl phosphate ribulose-5-phosphate ribose phosphribosylamine.

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

Aeukaryotic cell must be from a plant if the cell a) a nucleus b) a nuclear envelope c) cytoplasm d) a cell wall

If a checkpoint detects damaged dna, the checkpoint may