Name two cellular activities that require energy?

Answer 1

Many processes require energy, but here is a short list: * active transport This is the "pumping" of chemicals the opposite way to the way "they want to go". Substances naturally (passively) diffuse; that is, they show a net movement from higher to lower concentrations. To move a substance against (up) its concentration gradient, the cell needs energy, just as you need to expend energy to push a shopping cart up a ramp to the roof-top car park. Letting go is like diffusion! * synthesis reactionsSynthesis means the building of larger molecules from smaller ones, and it requires an input of energy. Examples include the synthesis of new DNA strands during DNA replication, synthesis of messenger RNA (mRNA) during transcription, polypeptide synthesis at ribosomes, and lipid synthesis in the smooth endoplasmic reticulum. * movement This includes the movements of the cell membrane during endocytosis and exocytosis (due to movement of the fibers of the cytoskeleton), and the movement of daughter-chromosomes to the poles during anaphase of mitosis and meiosis, again caused by the cytoskeleton, in this case in the form of the spindle fibers.

Answer 2

Cellular activities such as active transport of ions across the cell membrane and protein synthesis require energy in the form of ATP.

Answer 3

muscle movement, protein synthesis, cell division, photosynthesis etc..