Which piece of lab equipment is used to measure the mass of a chemical sample?

the sugar-phosphate backbone forms the structural framework of nucleic acids, including dna and rna. this backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.

after receiving a stimus, the sensory receptors send(s) signals to the appropriate area of the body.  

the must be sensory neurons.  

hope its .

true. until louis pasteur developed the rabies vaccine, “vaccines” had referred only to the cowpox inoculation for smallpox. hope this : )