Why do we have to close the windows during a fire drill?

In dna, only the_ varies from one nucleotide to another. base phosphate sugar amino acid

Nasa scientists must work together to make sure that everything is correct and accounted for when launching a shuttle. besides a physicist, what other type of scientist would be in making sure that the shuttle has the appropriate type and amount of fuel to reach its destination?

Diabetes is often suspected when glucose shows up in urine tests. use the model to explain how glucose could be present in urine. why do you think this symptom is especially concerning for young people?