Circadian rhythms ....its just behavior that is repeated over 24 hours
Eukaryotes have a nucleus with a membrane, larger ribosomal subunits, usually reproduce sexually, and may not have a cell wall. Prokaryotes have no membrane around the nucleus, smaller ribosomal subunits, reproduce asexually, and do have cell walls.
In the human respiratory system, gas exchange occurs across the cells of the alveoli. Alveoli or an alveolus is the deepest part of the human respiratory system. This part of the respiratory system is a place where gas exchange between oxygen and carbon dioxide occurs from inhaled air to the blood cells<span>.</span>
The structure of a carbohydrate(sugars) is Carbon, Hydrogen, and Oxygen.