Final answer:
Living organisms are made of cells, need energy, and have certain characteristics that define life.
Step-by-step explanation:
All organisms are made of one or more cells. Cells are the smallest unit of life and the building blocks of all living things. They carry out various functions and contain DNA that is passed on to daughter cells during cell division.
All living organisms need energy to carry out life processes. They obtain this energy through cellular respiration, which uses oxygen and lipids produced by photosynthesis. This process occurs in all organisms, whether they produce their own food through photosynthesis or obtain it from other sources.
All living organisms respond to their environment, grow, reproduce, and maintain a stable internal environment. These characteristics are common to all living things and define what it means to be alive.