Why are there usually fewer organisms at the top of an energy pyramid

My question says on my assignment. read the following scenarios and decide which of the properties of life are being described. the first one is. katherine stopped on the way to school to grab some donuts. 2. because a dog cannot sweat, it has to pant in order to stay cool. 3. an elephant trun had no bone but 4,000 muscles. i have no idea what i am supposed to anwer. i can't find the answer in my notes or book that i can understand anyway

What are the doorways into and out of cells, attached to the membrane, and built in the rough er.

During the process of two rails or sides break apart and attract new nucleotide bases to form a new and complete strand.