Which cell part is responsible for converting food into energy the cell can use?
ANucleus
BCell membrane
CMitochondria
DChloroplast
Mitochondria are the organelles that break down food molecules and release energy in a form the cell can use. The nucleus stores DNA, the cell membrane controls what enters and exits, and chloroplasts capture sunlight energy (only in plant cells).
Question 2 True / False
Mainly animal cells contain mitochondria.
TTrue
FFalse
Answer: False
Both plant and animal cells contain mitochondria. Plants need mitochondria to convert the sugars they make during photosynthesis into usable energy, just as animal cells need mitochondria to convert the sugars from food. Chloroplasts make the sugar; mitochondria release the energy from it.
Question 3 Short Answer
Describe the job of the cell membrane and explain why it is important for keeping the cell alive.
Think about your answer, then reveal below.
Model answer: The cell membrane controls what enters and leaves the cell. It lets in nutrients and water that the cell needs while keeping out harmful substances and preventing important molecules from leaking out. Without it, the cell could not maintain the right internal conditions to survive.
The cell membrane acts as a selective barrier. This function is critical because cells need specific concentrations of molecules to carry out life processes. A cell without a functioning membrane would lose its contents and die.