Beta cells in the pancreas and human skin cells
both contain the insulin gene. the beta cells can
make insulin; however, skin cells cannot. which
process is responsible for this gene being
expressed in one cell type and not in another
cell type?
(1) mitosis (3) differentiation
(2) replication (4) meiosis

Which of the following is not a way in which a vascular plant's xylem and phloem are similar?

Students in biology are studying the macromolecules of life. they used a calorimeter to determine the calories in various types of food. once the lab was completed, the students ate the left over food samples. monica commented that in just 6 or 7 "chews" of the saltine, it was gone; nothing but a sticky paste in her mouth. elaborate on what happened chemically while chewing the saltine. include the macromolecules present.

How can you tell the difference between rough er from smooth er?