1. The Cell Wall.
Plants have a cell wall in order to maintain rigidity and stability. Animal cells do not have a cell wall because they have a different structure, which makes them more flexible and able to move around easier.
2. Chloroplasts
Since plants cannot move, they get their energy from the sun. This energy is made inside of the chloroplasts. Animal cells don't have chloroplasts because their energy comes from other organisms.
3. Central Vacuole
The central vacuole provides structure and holds materials and wastes, and also decomposes those wastes. Animal cells don't have a central vacuole because they have lysosomes and normal vacuoles that do the same function.
Answer:
D. A bicycle rusting.
Explanation:
A. is incorrect because tearing a piece of paper is a physical change, not a chemical change.
B. is incorrect because we are just heating up the object. That only changes how fast the particles are moving and the change in state of matter.
C. is incorrect because we are adding heat to change a state of matter (from solid to liquid) and it is a physical change.
Therefore, only D. is the correct answer. Iron rusts, and when it does, it chemically changes into an iron oxide (rust).
Cells ?I believe :) hope this helps
