The Need for Energy
Investigate why cells need energy: all living cells require a continuous supply of energy to carry out life processes such as growth, reproduction, movement, and maintaining internal conditions.
Key Concepts
The universe runs on energy . It serves as the fundamental fuel for every action and event. Objects remain static until energy acts upon them to initiate movement or produce a change .
Rescue missions rely on essential devices like radios and flashlights, but these tools require a continuous supply of energy to function.
Common Questions
Why do cells need energy?
Cells need energy to perform all biological processes — building proteins, transporting materials across membranes, replicating DNA, moving, and maintaining internal temperature. Without energy, these processes stop and the cell dies.
Where do cells get their energy from?
Cells get energy from breaking down food molecules like glucose through cellular respiration. This process converts chemical energy stored in food into ATP, the molecule cells use to power their activities.
How is the need for energy studied in Grade 8 science?
Grade 8 students learn that energy flows through living systems, trace energy from sunlight to photosynthesis to cellular respiration, and connect this energy flow to the survival and functioning of all organisms.