Catabolite repression is characteristic for prokaryotic organisms such as bacteria and this is the way to control metabolism.
It is called repression, because enzymes that are involved in other sugar's metabolism are inhibited (repressed). The system of catabolite repression have components such as:
sensory systems-detects ratios of glycolytic intermediates,
global regulators-control the expression of genes that encode for enzymes.
To maintain homeostasis, unicellular organisms grow, respond to the environment, transform energy, and reproduce. A single-celled, or unicellular, organism does everything you would expect a living thing to do.
